RESUMEN
Cryofixation by high-pressure freezing (HPF) followed by freeze substitution (FS) is a preferred method to prepare biological specimens for ultrastructural studies. It has been shown to achieve uniform vitrification and ultrastructure preservation of complex structures in different cell types. One limitation of HPF is the small sample volume of <200 µm thickness and about 2000 µm across. A wool follicle is a rare intact organ in a single sample about 200 µm thick. Within each follicle, specialized cells derived from multiple cell lineages assemble, mature and cornify to make a wool fibre, which contains 95% keratin and associated proteins. In addition to their complex structure, large density changes occur during wool fibre development. Limited water movement and accessibility of fixatives are some issues that negatively affect the preservation of the follicle ultrastructure via conventional chemical processing. Here, we show that HPF-FS of wool follicles can yield high-quality tissue preservation for ultrastructural studies using transmission electron microscopy.
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Criopreservación/métodos , Substitución por Congelación/métodos , Folículo Piloso/ultraestructura , Lana/ultraestructura , Animales , Congelación , Microscopía Electrónica de Transmisión/métodos , Ovinos , VitrificaciónRESUMEN
OBJECTIVE: A new hair-care process has been specifically developed for the straightening of curved Japanese woman's hair . The process included sodium 2-naphthalene sulfonate (SNS) in the reduction and oxidation steps of a conventional perming process. Our objective was to develop an understanding of how this process caused hair straightening by measuring the changes to morphology and ultrastructure between untreated, conventionally permed and SNS permed hair. Untreated and SNS permed Merino wool fibres were used to confirm structural changes. METHODS: Japanese hair samples were measured for single-fibre curvature before and after perming treatments. A silver staining method was developed to stain hair fibres without changing fibre curvature so that transmission electron microscopy could be used to measure changes in the lateral dimensions of all structural components from the cellular to protein filament level. Electron tomography determined intermediate filament slopes and slope changes after SNS perming relative to the central longitudinal axis of the fibre. RESULTS: SNS perming was found to cause greater lateral swelling than conventional perming of: the paracortical cells of wool; the cuticle, the cuticular cell membrane complex and the macrofibrillar centre-to-centre distance of hair; and of the intermediate filaments in wool and hair. In curved hair, SNS perming caused the intermediate filaments of the helical macrofibrils to simultaneously swell and to tilt further, resulting in the slight longitudinal contraction of the macrofibrils. The overall swelling and tilting was greatest in the helical macrofibrils of Type B cortical cells predominately located in the convex fibre half. The presence of a higher percentage of helical macrofibrils in the convex fibre half than in the concave fibre half caused a contraction differential between the two halves leading to straighten of the curved fibre. A mechanical model was proposed to explain how SNS perming straightened curly hair. CONCLUSION: The effects of conventional and SNS perming on the morphological and ultrastructural components of curved Japanese hair and high-curl Merino wool fibres have given clear insights into understanding the mechanism of fibre curvature change.
OBJECTIF: Un nouveau procédé de soin des cheveux a été spécialement conçu pour lisser les cheveux ondulés des Japonaises[1]. Le procédé utilise le sulfonate de naphthalène-2 sodium (SNS) dans les étapes de réduction et d'oxydation du procédé conventionnel de permanente. Notre objectif était de comprendre la façon dont ce procédé induisait le lissage des cheveux en mesurant les différences de changement morphologique et ultrastructural entre les cheveux non traités et ceux soumis à une permanente conventionnelle et une permanente à base de SNS. Des fibres de laine de mérinos non traitées et soumises à une permanente à base de SNS ont été utilisées pour confirmer les changements structurels. MÉTHODES: Des échantillons de cheveux japonais ont été utilisés pour mesurer la courbure d'une fibre isolée avant et après le traitement de permanente. Une méthode de coloration argent a été mise au point pour colorer les fibres de cheveux sans changer la courbure des fibres afin de pouvoir utiliser la microscopie électronique en transmission pour mesurer les modifications des dimensions en largeur de tous les composants structurels du filament, de la cellule aux protéines. Une tomographie électronique a déterminé les pentes intermédiaires et les changements de pente des filaments après permanente à base de SNS par rapport à l'axe longitudinal central de la fibre. RÉSULTATS: On a constaté que la permanente à base de SNS induisait un gonflement en largeur plus important que la permanente classique des cellules paracorticales de la laine; de la cuticule, du complexe de la membrane cellulaire cuticulaire et de la distance centre à centre des macrofibrilles du cheveu; et des filaments intermédiaires dans la laine et les cheveux. Dans les cheveux ondulés, la permanente à base de SNS a provoqué à la fois un gonflement et une inclinaison des filaments intermédiaires des macrofibrilles hélicoïdales, entraînant une légère contraction longitudinale des macrofibrilles. Au total, le gonflement et l'inclinaison étaient plus importants dans les macrofibrilles hélicoïdales des cellules corticales de type B situées principalement dans la moitié convexe de la fibre. La présence d'un pourcentage plus élevé de macrofibrilles hélicoïdales dans la moitié convexe par rapport à la moitié concave de la fibre a entraîné une contraction différentielle entre les deux moitiés qui a entraîné le redressement de la fibre courbée. Un modèle mécanique a été proposé pour expliquer comment la permanente à base de SNS lissait les cheveux bouclés. CONCLUSION: Les effets de la permanente conventionnelle et à base de SNS sur les composants morphologiques et ultrastructuraux des cheveux japonais ondulés et des fibres de laine très frisés de mérinos ont permis de mieux comprendre le mécanisme du changement de courbure des fibres.
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Preparaciones para el Cabello , Cabello/química , Microscopía Electrónica de Transmisión/métodos , Naftalenosulfonatos/química , Tomografía/métodos , Animales , Pueblo Asiatico , Femenino , Cabello/ultraestructura , Humanos , Japón , OvinosRESUMEN
Although performing aerial maneuvers can increase wave score and winning potential in competitive surfing, the critical features underlying successful aerial performance have not been systematically investigated. This study aimed to analyze highly skilled aerial maneuver performance and to identify the critical features associated with successful or unsuccessful landing. Using video recordings of the World Surf League's Championship Tour, every aerial performed during the quarterfinal, semifinal, and final heats from the 11 events in the 2015 season was viewed. From this, 121 aerials were identified with the Frontside Air (n = 15) and Frontside Air Reverse (n = 67) being selected to be qualitatively assessed. Using chi-squared analyses, a series of key critical features, including landing over the center of the surfboard (FS Air χ2 = 14.00, FS Air Reverse χ2 = 26.61; P < .001) and landing with the lead ankle in dorsiflexion (FS Air χ2 = 3.90, FS Air Reverse χ2 = 13.64; P < .05), were found to be associated with successful landings. These critical features help surfers land in a stable position, while maintaining contact with the surfboard. The results of this study provide coaches with evidence to adjust the technique of their athletes to improve their winning potential.
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Rendimiento Atlético/normas , Deportes/normas , Adulto , Atletas , Humanos , Masculino , Equilibrio Postural , Rango del Movimiento Articular , Grabación en Video , Adulto JovenRESUMEN
BACKGROUND: Transition of hair shaft keratinocytes from actively respiring, nucleated cells to structural cells devoid of nucleus and cytoplasm is key to hair production. This form of cell 'death', or cornification, requires cellular organelle removal to allow the cytoplasm to become packed with keratin filament bundles that further require cross-linking to create a strong hair fibre. Although these processes are well described in epidermal keratinocytes, there is a lack of understanding of such mechanisms, specifically in the hair follicle. OBJECTIVES: To gain insights into cornification mechanisms within the hair follicle and thus improve our understanding of normal hair physiology. METHODS: Scalp biopsies and hair-pluck samples were obtained from healthy human donors and analysed microscopically after immunohistochemical staining. RESULTS: A focal point of respiratory activity was evident in keratogenous zone cells within the hair shaft, which also exhibited nuclear damage. Nuclear degradation occurred via both caspase-dependent and caspase-independent pathways. Conversely, mitophagy was driven by Bnip3L and restricted to the boundary of the keratogenous zone at Adamson's Fringe. CONCLUSIONS: We propose a model of stepwise living-dead transition within the first 1 mm of hair formation, whereby fully functional, nucleated cells first consolidate required functions by degrading nuclear DNA, yet continue to respire and provide the source of reactive oxygen species required for keratin cross-linking. Finally, as the cells become packed with keratin bundles, Bnip3L expression triggers mitophagy to rid the cells of the last remaining 'living' characteristic, thus completing the march from 'living' to 'dead' within the hair follicle.
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Cabello/crecimiento & desarrollo , Queratinocitos/citología , Orgánulos/ultraestructura , Adolescente , Adulto , Anciano , Apoptosis/fisiología , Autofagia/fisiología , Muerte Celular/fisiología , Diferenciación Celular , Núcleo Celular/ultraestructura , Reactivos de Enlaces Cruzados/metabolismo , Femenino , Cabello/citología , Cabello/ultraestructura , Folículo Piloso/citología , Folículo Piloso/crecimiento & desarrollo , Folículo Piloso/ultraestructura , Voluntarios Sanos , Humanos , Queratinocitos/ultraestructura , Queratinas/metabolismo , Microscopía Confocal , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Mitocondrias/ultraestructura , Oxidación-Reducción , Estrés Oxidativo/fisiología , Cuero Cabelludo/citología , Cuero Cabelludo/crecimiento & desarrollo , Cuero Cabelludo/ultraestructura , Adulto JovenRESUMEN
BACKGROUND: One previous pilot study suggested the association of low plasma glucosylceramide (GlcCer) levels with venous thrombosis (VTE) risk. OBJECTIVE: We aimed to confirm and evaluate the association of low plasma GlcCer levels with VTE and myocardial infarction (MI) occurrence, respectively. PATIENTS AND METHODS: We evaluated the association of GlcCer in two independent case-control studies of Caucasian VTE populations (N = 210 and 636) and one case-control study of Caucasian MI patients (N = 345). RESULT: Plasma GlcCer levels in VTE patients were lower compared to controls in two independent VTE populations (5.0 vs 5.8 µg/mL, p = 0.003 for the Scripps registry, and 5.6 vs 6.0 µg/mL, p = 0.001 for the Valencia registry, respectively). A low plasma GlcCer level (below 10th percentile of controls) was associated with increased VTE occurrence [odds ratio (OR) = 3.7 (95%CI, 1.8-7.9) for Scripps registry and OR = 2.1 (95%CI, 1.3-3.3) for Valencia registry, respectively). For the MI study, the median GlcCer plasma level was lower in MI patients than in controls (4.3 vs 5.6 µg/mL, p<0.001), and a low level of GlcCer (below 10th percentile of control) was associated with higher MI occurrence [OR = 7.7, (95%CI, 4.3-13.8)]. CONCLUSION: Lower concentration of GlcCer was associated with VTE occurrence in two independent studies and also with MI occurrence in one study.
RESUMEN
OBJECTIVE: Exposure to UV in humans resulting in sunburn triggers a complex series of events that are a mix of immediate and delayed damage mediation and healing. While studies on the effects of UV exposure on DNA damage and repair have been reported, changes in the oxidative modification of skin proteins are poorly understood at the molecular level, despite the important role played by structural proteins in skin tissue, and the effect of the integrity of these proteins on skin appearance and health. Proteomic molecular mapping of oxidation was here applied to try to enhance understanding of skin damage and recovery from oxidative damage and UVB exposure. METHODS: A redox proteomic-based approach was applied to evaluating skin protein modification when exposed to varying doses of UVB after initial oxidative stress, via tracking changes in protein oxidation during the healing process in vitro using a full-thickness reconstituted human skin tissue model. Bioassays and structural evaluation confirmed that our cultured skin tissues underwent a normal physiological response to UVB exposure. RESULTS: A set of potential skin marker peptides was generated, for use in tracking skin protein oxidative modification. Exposure to UVB after thermal oxidative stress was found to result in higher levels of skin protein oxidation than a non-irradiated control for up to seven days after exposure. Recovery of the skin proteins from oxidative stress, as assessed by the overall protein oxidation levels, was found to be impaired by UVB exposure. Oxidative modification was largely observed in skin structural proteins. CONCLUSION: Exposure of skin proteins to UVB exacerbates oxidative damage to structural skin proteins, with higher exposure levels leading to increasingly impaired recovery from this damage. This has potential implications for the functional performance of the proteins and inter-related skin health and cosmetic appearance.
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Modelos Biológicos , Estrés Oxidativo , Proteómica , Piel/efectos de la radiación , Rayos Ultravioleta , Humanos , Oxidación-Reducción , Piel/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Venous thromboembolism (VTE) affects more than 300,000 people in the United States each year. However, it has been estimated that current diagnostic testing fails to identify prothrombotic risk in 50% of VTE patients. This article examines the relationship between levels of the pro-coagulant proteins factor VIII (FVIII), von Willebrand factor (VWF), and fibrinogen and risk of VTE in order to assess the impact of these novel risk factors. Data were collected from patients enrolled in the matched case-control Genetic Attributes and Thrombosis Epidemiology study. Crude and adjusted conditional logistic regression models were used to assess the impact of FVIII, VWF, and fibrinogen on risk of VTE. Before adjustment for independent predictors of VTE risk, high levels of FVIII, VWF, and fibrinogen were significantly associated with increased risk of VTE in both Blacks and Whites. After adjustment for ABO type, factor VII levels, hypertension, renal disease, recent surgery, diabetes, annual household income, alcohol use, and the other proteins of interest (FVIII, VWF, and/or fibrinogen), high FVIII and VWF levels were associated with increased risk of VTE in Blacks (OR: 1.97 [1.01-3.84] and 3.39 [1.58-7.27], respectively). High FVIII only was significantly associated with risk of VTE in Whites (OR: 2.35 [1.16-4.75]). Future research into the inclusion of these protein levels in risk models for VTE could help identify persons at highest risk.
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Población Negra/estadística & datos numéricos , Factor VIII/metabolismo , Fibrinógeno/metabolismo , Tromboembolia Venosa/sangre , Tromboembolia Venosa/etnología , Población Blanca/estadística & datos numéricos , Factor de von Willebrand/metabolismo , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos/epidemiología , Tromboembolia Venosa/epidemiologíaRESUMEN
OBJECTIVE: Protein modification and damage in human hair, resulting from environmental, cosmetic and grooming stresses, create changes to visual and tactile characteristics and correlates with consumer perception of quality. This study outlines molecular-level evaluation of modification resulting from peroxide (bleaching) and alkaline straightening (relaxing) treatments. METHODS: Redox proteomic profiling of virgin, bleached and relaxed hair tresses was performed, with comprehensive qualitative characterization of modification and semi-quantitative evaluation of damage through adaptation of a new damage scoring system. Modifications were mapped to specific locations in the hair proteome and a range of potential damage marker peptides identified. RESULTS: Virgin hair contained a baseline level of modification, consistent with environmental oxidative insult during hair growth. Hydrogen peroxide bleaching resulted in significantly increased levels of oxidative damage observable at the molecular level. This treatment also resulted in enhanced levels of dehydroalanine and dehydration products; modifications typically associated with alkali or thermal treatment and not previously been reported as a product of hair bleaching. Relaxation treatment with sodium hydroxide increased the formation of dehydroalanine and dehydration products and moderately enhanced the levels of oxidation. Cysteine was the predominant modification site for both bleaching and alkali damage. CONCLUSION: This study validates the utility and power of redox proteomic-based approaches to characterizing hair modification. This offers potential application to a wide range of damage types, as well as evaluation of new damage mitigation and repair technologies.
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Álcalis/química , Preparaciones para el Cabello/química , Cabello/química , Peróxido de Hidrógeno/química , Proteómica/métodos , Álcalis/efectos adversos , Cromatografía Liquida , Biología Computacional , Preparaciones para el Cabello/efectos adversos , Humanos , Peróxido de Hidrógeno/efectos adversos , Oxidación-Reducción , Espectrometría de Masas en TándemRESUMEN
The chick chorioallantoic membrane (CAM) subserves gas exchange in the developing embryo and shell-less culture affords a unique opportunity for direct observations over time of individual blood vessels to pharmacologic interventions. We tested a number of lipids including prostaglandins PGE(1&2) for vascular effects and signaling in the CAM. Application of PGE(1&2) induced a decrease in the diameter of large blood vessels and a concentration-dependent, localized, reversible loss of blood flow through small vessels. The loss of flow was also mimicked by misoprostol, an agonist for 3 of 4 known PGE receptors, EP(2-4), and by U46619, a thromboxane mimetic. Selective receptor antagonists for EP(3) and thromboxane each partially blocked the response. This is a first report of the effects of prostaglandins on vasoreactivity in the CAM. Our model allows the unique ability to examine simultaneous responses of large and small vessels in real time and in vivo.
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Alprostadil/farmacología , Membrana Corioalantoides/efectos de los fármacos , Dinoprostona/farmacología , Vasoconstrictores/farmacología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacología , Alprostadil/antagonistas & inhibidores , Animales , Compuestos de Bifenilo/farmacología , Vasos Sanguíneos/efectos de los fármacos , Vasos Sanguíneos/fisiología , Compuestos Bicíclicos Heterocíclicos con Puentes , Embrión de Pollo , Membrana Corioalantoides/irrigación sanguínea , Membrana Corioalantoides/metabolismo , Ácido Dibenzo(b,f)(1,4)oxazepina-10(11H)-carboxílico, 8-cloro-, 2-acetilhidrazida/farmacología , Dinoprostona/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Estradiol/farmacología , Estrógenos/farmacología , Ácidos Grasos Insaturados , Hidrazinas/farmacología , Microsomas/efectos de los fármacos , Microsomas/metabolismo , Misoprostol/farmacología , Antagonistas de Prostaglandina/farmacología , Ratas , Receptores de Prostaglandina/agonistas , Receptores de Prostaglandina/antagonistas & inhibidores , Receptores de Prostaglandina/metabolismo , Receptores de Tromboxanos/agonistas , Receptores de Tromboxanos/antagonistas & inhibidores , Receptores de Tromboxanos/metabolismo , Vasoconstricción/efectos de los fármacos , Vasoconstrictores/antagonistas & inhibidores , Xantonas/farmacología , Ácido alfa-Linolénico/farmacologíaRESUMEN
For wool, superior staining of a wide range of ultrastructural components is achieved by en bloc treatment of fibres with a chemical reductant followed by osmium tetroxide. For human scalp hair, although staining quality is similar, the penetration of reagents is poor, resulting in large parts of the fibre cortex remaining unstained. Here we describe a modification to the reduction-osmication method in which reagents penetrate through a cut fibre end, allowing visualization of a wide range of features across the cortex. We compare the staining quality, artefacts and range of structure rendered visible using transmission electron microscopy for en bloc reduction-osmication to other staining alternatives including en bloc silver nitrate and section stains based on uranyl acetate and lead citrate, phosphotungstic acid, potassium permanganate, ammoniacal silver nitrate and some combinations of these stains. The effects of hair-care treatments are briefly examined.
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Cabello/ultraestructura , Microscopía Electrónica de Transmisión/métodos , Tetróxido de Osmio , Coloración y Etiquetado/métodos , Colorantes , Femenino , Cabello/efectos de los fármacos , Preparaciones para el Cabello/farmacología , Técnicas Histológicas , Humanos , Plomo , Compuestos Organometálicos , Oxidación-Reducción , Ácido Fosfotúngstico , Permanganato de Potasio , Plata , Nitrato de PlataRESUMEN
We provide a detailed description of the ultrastructure of deer hair fibers. Guard hairs and underhairs from the winter coat of red deer (Cervus elaphus), and antler velvet hairs from the same species were examined. All fibers displayed the typical keratin fiber morphology of overlapping cuticle cells surrounding a core of cortex cells, and often a centrally-located medulla, but there were considerable differences in the diameter, cuticle thickness, and scale pattern, and in the relative amounts of cortex and medulla along individual fibers, and between the different types of fiber. In addition, closer examination of cortex cells using transmission electron microscopy revealed considerable differences in the arrangement of intermediate filaments in the different fiber types. Fine underhairs appeared similar to fine wool fibers from sheep because intermediate filament arrangements were very similar to those found in wool orthocortex cells and paracortex cells. In addition, a similar bilateral distribution of these cell types was evident. However, in the antler velvet hairs and the guard hairs, intermediate filament arrangements were more variable and complex, and showed similarities to those in heterotype cortex cells described for human hair.
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Cuernos de Venado/anatomía & histología , Ciervos/anatomía & histología , Cabello/anatomía & histología , Animales , Cuernos de Venado/ultraestructura , Cabello/ultraestructura , Filamentos Intermedios/ultraestructura , Microscopía Electrónica de TransmisiónRESUMEN
OBJECTIVE: There is debate as to the effects of obesity on the developing feet of children. We aimed to determine whether the flatter foot structure characteristic of obese primary school-aged children was due to increased medial midfoot plantar fat pad thickness (fat feet) or due to structural lowering of the longitudinal arch (flat feet). METHODS AND PROCEDURES: Participants were 75 obese children (8.3 ± 1.1 years, 26 boys, BMI 25.2 ± 3.6 kg m(-2)) and 75 age- and sex-matched non-obese children (8.3 ± 0.9 years, BMI 15.9 ± 1.4 kg m(-2)). Height, weight and foot dimensions were measured with standard instrumentation. Medial midfoot plantar fat pad thickness and internal arch height were quantified using ultrasonography. RESULTS: Obese children had significantly greater medial midfoot fat pad thickness relative to the leaner children during both non-weight bearing (5.4 and 4.6 mm, respectively; P<0.001) and weight bearing (4.7 and 4.3 mm, respectively; P < 0.001). The obese children also displayed a lowered medial longitudinal arch height when compared to their leaner counterparts (23.5 and 24.5 mm, respectively; P = 0.006). CONCLUSION: Obese children had significantly fatter and flatter feet compared to normal weight children. The functional and clinical relevance of the increased fatness and flatness values for the obese children remains unknown.
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Tejido Adiposo/patología , Estatura , Peso Corporal , Pie Plano/patología , Pie/patología , Obesidad/patología , Tejido Adiposo/diagnóstico por imagen , Índice de Masa Corporal , Estudios de Casos y Controles , Niño , Femenino , Pie Plano/epidemiología , Pie Plano/etiología , Pie/diagnóstico por imagen , Humanos , Estudios Longitudinales , Masculino , Estudios Multicéntricos como Asunto , Obesidad/complicaciones , Obesidad/epidemiología , Presión , Ensayos Clínicos Controlados Aleatorios como Asunto , Ultrasonografía , Soporte de PesoRESUMEN
PURPOSE: Little is known about the potential carcinogenicity of the triazinone herbicide metribuzin. We evaluated the association between metribuzin use and cancer risk in the Agricultural Health Study, a prospective cohort study of licensed pesticide applicators in Iowa and North Carolina. METHODS: Applicators (N=23,072) provided information on metribuzin use on a self-administered questionnaire at enrollment (1993-1997). Among metribuzin users (n=8,504), there were 554 incident cancer cases. We used multivariable Poisson regression to evaluate potential associations between metribuzin use and cancer incidence by using two quantitative exposure metrics, lifetime days and intensity-weighted lifetime days. RESULTS: Using intensity-weighted lifetime days, the rate ratio (RR) and 95% confidence interval (CI) for the highest exposed tertile for lymphohematopoietic malignancies were 2.09 (95% CI: 0.99-4.29), p trend=0.02 and 2.42 (95% CI: 0.82-7.19), p trend=0.08 for leukemia. For non-Hodgkin lymphoma, the RR was 2.64 (95% CI: 0.76-9.11), p trend=0.13 for lifetime days and 2.52 (95% CI: 0.66-9.59), p trend=0.13 for intensity-weighted lifetime days. Patterns of association were similar for both exposure metrics, but associations were generally weaker than for intensity-weighted days. CONCLUSIONS: The results from this study suggest a potential association between metribuzin use and certain lymphohematopoietic malignancies; however, having not been observed previously, caution should be used in interpretation.
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Herbicidas/toxicidad , Neoplasias/epidemiología , Exposición Profesional/análisis , Triazinas/toxicidad , Adulto , Anciano , Agricultura , Carcinógenos/toxicidad , Estudios de Cohortes , Femenino , Neoplasias Hematológicas/epidemiología , Humanos , Iowa/epidemiología , Leucemia/epidemiología , Linfoma/epidemiología , Masculino , Persona de Mediana Edad , North Carolina/epidemiología , Factores de Riesgo , Encuestas y CuestionariosRESUMEN
OBJECTIVES: To estimate the incidence of herpes simplex type 2 virus (HSV-2) infection, to identify risk factors for its acquisition, and to assess the protective effect of condoms. STUDY DESIGN: Prospective study of 293 HSV-2 seronegative women, aged 18 to 35 years, attending a sexually transmitted disease clinic in Alabama from 1992 to 1995. RESULTS: Incidence of HSV-2 infection was 20.5 per 100 woman-years [95% confidence interval (CI), 13.1-30.5]. Young women (18-20 years) had a significantly higher risk of incident HSV-2 infection [adjusted hazard ratio (HR), 2.8; 95% CI, 1.3-6.4] than older women. Women diagnosed with prevalent or incident bacterial vaginosis had a higher incidence of HSV-2 infection than those who were not so diagnosed (adjusted HR, 2.4; 95% CI, 1.1-5.6). No significant protective effect was observed for consistent (100%) condom use without breakage and slippage against HSV-2 acquisition (adjusted HR, 0.8; 95% CI, 0.2-2.3). CONCLUSION: Acquisition of HSV-2 infection among study participants was higher than previous estimates for adult female sexually transmitted disease clinic attendees, and no protective effect for condoms was demonstrated. The high incidence of HSV-2 infection with its potential for adverse health consequences emphasizes the need for better prevention strategies.
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Herpes Genital/epidemiología , Herpes Genital/prevención & control , Herpesvirus Humano 2 , Adolescente , Adulto , Alabama/epidemiología , Instituciones de Atención Ambulatoria , Estudios de Cohortes , Condones/estadística & datos numéricos , Femenino , Herpes Genital/sangre , Herpes Genital/etiología , Herpes Genital/virología , Humanos , Incidencia , Masculino , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Factores SexualesRESUMEN
Asthma was associated with atherosclerotic disease in several studies, with evidence that this association may be limited to women. However, most previous studies failed to account for the heterogeneity of asthma subtypes. We previously reported increased carotid intima-medial thickness in women with adult-onset asthma. In this study, the association of adult- and child-onset asthma with incident coronary heart disease (CHD) and stroke were examined. Subjects were classified according to self-report of physician-diagnosed asthma and age of asthma onset. Cox proportional hazards models were used to test the association of adult- and child-onset asthma with incident CHD and stroke, testing for gender interaction. Subanalysis was also performed using only never smokers. Women with adult-onset asthma experienced a 2-fold increase in incident CHD and stroke that was independent of other risk factors, including smoking, body mass index, and physical activity, and persisted when analysis was restricted to never smokers. No significant association was found in women with child-onset asthma or in men. In conclusion, adult-onset asthma may be a significant risk factor for CHD and stroke in women, but not men.
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Asma/complicaciones , Enfermedad Coronaria/epidemiología , Accidente Cerebrovascular/epidemiología , Edad de Inicio , Índice de Masa Corporal , Distribución de Chi-Cuadrado , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología , Estados Unidos/epidemiologíaRESUMEN
PURPOSE: The objective of this study was to estimate the burden of cancer in counties affected by Hurricane Katrina using population-based cancer registry data, and to discuss issues related to cancer patients who have been displaced by disasters. METHODS: The cancer burden was assessed in 75 counties in Louisiana, Alabama, and Mississippi that were designated by the Federal Emergency Management Agency as eligible for individual and public assistance. Data from the National Program of Cancer Registries were used to determine three-year average annual age-adjusted incidence rates and case counts during the diagnosis years 2000-2002 for Louisiana and Alabama. Expected rates and counts for the most-affected counties in Mississippi were estimated by direct, age-specific calculation using the 2000-2002 county level populations and the site-, sex-, race-, and age-specific cancer incidence rates for Louisiana. RESULTS: An estimated 23,549 persons with a new diagnosis of cancer in the past year resided in the disaster-affected counties. Fifty-eight percent of the cases were cancers of the lung/bronchus, colon/rectum, female breast, and prostate. Eleven of the top 15 cancer sites by sex and black/white race in disaster counties had >50% of cases diagnosed at the regional or distant stage. CONCLUSIONS: Sizable populations of persons with a recent cancer diagnosis were potentially displaced by Hurricane Katrina. Cancer patients required special attention to access records in order to confirm diagnosis and staging, minimize disruption in treatment, and ensure coverage of care. Cancer registry data can be used to provide disaster planners and clinicians with estimates of the number of cancer patients, many of whom may be undergoing active treatment.
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Planificación en Desastres/métodos , Desastres , Neoplasias/epidemiología , Administración en Salud Pública , Refugiados/estadística & datos numéricos , Programa de VERF/estadística & datos numéricos , Adolescente , Adulto , Negro o Afroamericano/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Alabama/epidemiología , Niño , Servicios Médicos de Urgencia , Femenino , Disparidades en el Estado de Salud , Humanos , Incidencia , Louisiana/epidemiología , Masculino , Persona de Mediana Edad , Mississippi/epidemiología , Neoplasias/etnología , Población Blanca/estadística & datos numéricosRESUMEN
PURPOSE: There have been concerns among pediatric oncologists that adolescent and minority patients are not getting adequate access to care. This study examines access to cancer care and survival outcomes based on age, race, and type of cancer in patients in Georgia. PATIENTS AND METHODS: We performed a retrospective review of 1,751 cancer patients aged 0 to 19 years, diagnosed between 1998 and 2002, in the Georgia Comprehensive Cancer Registry, which identified patients who were treated at one of five Georgia pediatric cancer centers (Children's Oncology Group [COG] members) at any point in their treatment. Data were further analyzed for age at diagnosis, race, county of residence, and 5-year survival. RESULTS: Eighty-seven percent of patients aged 0 to 14 years and 36% of those aged 15 to 19 years were treated at a COG institution. Twenty-five percent of all patients were of African descent, with 75.4% of black versus 70.3% of white patients (age 0 to 19 years) treated at a COG institution (P < .01); 97.1% of other minorities were treated at a COG institution (P < .05). The 5-year actuarial survival rates for more pediatric-specific cancers were significantly lower in all leukemias (75.1% v 46.4%; P = .0015), and acute lymphoblastic leukemia specifically (86.3% v 53.3%; P < .05) for patients not treated at a COG institution. Actuarial survival rates were much lower for blacks than whites in all cancers as a whole (70% v 82%; P < .001) and for many specific subtypes. CONCLUSION: Adolescent-aged patients are less likely to be referred to a COG institution, potentially exposing them to worse outcomes in some cancer subtypes. Reassuringly, minority populations are receiving adequate access to pediatric cancer care; unfortunately their survival rates are lower.
Asunto(s)
Accesibilidad a los Servicios de Salud , Neoplasias/diagnóstico , Neoplasias/terapia , Adolescente , Adulto , Niño , Preescolar , Femenino , Georgia , Humanos , Lactante , Recién Nacido , Masculino , Neoplasias/etnología , Neoplasias/mortalidad , Oportunidad Relativa , Análisis de Regresión , Resultado del TratamientoRESUMEN
All jumping spiders have unique, complex eyes with exceptional spatial acuity and some of the most elaborate vision-guided predatory strategies ever documented for any animal of their size. However, it is only recently that phylogenetic techniques have been used to reconstruct the relationships and key evolutionary events within the Salticidae. Here, we used data for 35 species and six genes (4.8 kb) for reconstructing the phylogenetic relationships between Spartaeinae, Lyssomaninae and Salticoida. We document a remarkable case of morphological convergence of eye ultrastructure in two clades with divergent predatory behaviour. We, furthermore, find evidence for a stepwise, gradual evolution of a complex predatory strategy. Divergent predatory behaviour ranges from cursorial hunting to building prey-catching webs and araneophagy with web invasion and aggressive mimicry. Web invasion and aggressive mimicry evolved once from an ancestral spartaeine that was already araneophagic and had no difficulty entering webs due to glue immunity. Web invasion and aggressive mimicry was lost once, in Paracyrba, which has replaced one highly specialized predation strategy with another (hunting mosquitoes). In contrast to the evolution of divergent behaviour, eyes with similarly high spatial acuity and ultrastructural design evolved convergently in the Salticoida and in Portia.
Asunto(s)
Evolución Biológica , Conducta Predatoria/fisiología , Arañas/genética , Arañas/fisiología , Animales , Ojo/ultraestructura , Visión Ocular/genética , Visión Ocular/fisiologíaRESUMEN
BACKGROUND: Studies of condom use to reduce risk of most sexually transmitted infection provide inconsistent results. This inconsistency is often attributed to methodologic limitations yet has not been assessed systematically. OBJECTIVES: The objectives of this study were to review studies of condom use and risk of gonorrhea and chlamydia, and to evaluate the importance of 4 key design and measurement factors on condom effectiveness estimates. DESIGN: We reviewed studies published 1966-2004 to assess risk reduction for gonorrhea and/or chlamydia associated with male condom use. RESULTS: Of 45 studies identified, most found reduced risk of infection associated with condom use. All studies reviewed had methodologic limitations: only 28 (62%) distinguished consistent from inconsistent use; 2 (4%) reported on correct use or use problems; 13 (29%) distinguished incident from prevalent infection; and one (2%) included a population with documented exposure to infection. Eight of 10 studies with 2 or more of these attributes reported statistically significant protective effects for condom use versus 15 of 35 studies with zero or one attribute (80% vs. 43%, P = 0.04). CONCLUSIONS: Condom use was associated with reduced risk of gonorrhea and chlamydia in men and women in most studies, despite methodologic limitations that likely underestimate condom effectiveness. Epidemiologic studies that better address these factors are needed to provide more accurate assessment of condom effectiveness.