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1.
J Eur Acad Dermatol Venereol ; 34(2): 377-384, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31494974

RESUMEN

BACKGROUND: Chronic viral infections caused by highly contagious human papillomaviruses (HPVs) from the alpha genus are a substantial risk factor for tumour diseases. OBJECTIVES: The goal of this study was to compare the HPV infection pattern with histology in a patient group of immunocompromised HIV+ and non-immunocompromised patients with anal intraepithelial neoplasia. MATERIALS AND METHODS: Tissue samples (n = 210) from the anogenital area of 121 patients underwent retrospective histological and molecular examination for HPV DNA prevalence by chip analysis. The study was part of a cancer screening from the Dermatology Department of the LMU Munich, Germany. All data were collected and processed anonymously. RESULTS: HPV 6 or 11 are more abundant in tissue samples from histologically diagnosed condylomata acuminata (47.7%) compared to grade 1, 2, and 3 intraepithelial neoplasias (IN 1-3). Detection of high-risk (hr) alpha-HPV DNA was significantly higher in tissue samples from IN 3 (67.5%) compared to IN 1 and 2 (12.9%), and compared to condylomata acuminata (29.5%). No HPV types were detected in histologically unremarkable tissue samples. There was a significant association between the prevalence of HPV 16 and the classifications IN 1 to IN 3 (χ2 (2) = 13.62, P = 0.001). We identified a significant correlation between the prevalence of high-risk and low-risk (lr) HPV types and HIV, especially mixed infections of different HPV types correlated with high-grade IN. Based on the present data, we suggest the risk of carcinoma in HIV+/- patients (RICH) score and test it in the 121 patients. CONCLUSIONS: hr alpha-HPVs, mainly HPV 16, are associated with increased oncogenic potential of premalignant lesions (IN 1-3), especially in HIV+ patients. Based on the combination of HIV/HPV-testing and histological analysis, we identified correlations that could potentially forecast the risk of malignant transformation and summarized them in the form of RICH score.


Asunto(s)
Alphapapillomavirus/aislamiento & purificación , Neoplasias del Ano/virología , Infecciones por VIH/complicaciones , Infecciones por Papillomavirus/virología , Infecciones Tumorales por Virus/virología , Neoplasias del Cuello Uterino/virología , Adulto , Neoplasias del Ano/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Papillomavirus/complicaciones , Estudios Retrospectivos , Infecciones Tumorales por Virus/complicaciones , Neoplasias del Cuello Uterino/complicaciones
2.
J Acoust Soc Am ; 132(3): EL169-75, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22979828

RESUMEN

Simultaneous long-term monitoring of underwater sound and ship traffic provided an opportunity to study how low-frequency noise correlated with ocean-based commercial shipping trends. Between 2007 and 2010 changes in regional shipping off southern California occurred as a consequence of economic and regulatory events. Underwater average noise levels measured before and during these events showed a net reduction of 12 dB. Statistical models revealed that a reduction of 1 ship transit per day resulted in 1 dB decrease in average noise. This synthesis of maritime traffic statistics with ocean noise monitoring provides an important step in understanding the magnitude and potential effects of chronic noise in marine habitats.


Asunto(s)
Recesión Económica , Ruido del Transporte/prevención & control , Navíos/economía , Recesión Económica/tendencias , Ecosistema , Monitoreo del Ambiente/métodos , Análisis de Fourier , Modelos Estadísticos , Movimiento (Física) , Ruido del Transporte/economía , Ruido del Transporte/estadística & datos numéricos , Océanos y Mares , Navíos/legislación & jurisprudencia , Navíos/estadística & datos numéricos , Sonido , Espectrografía del Sonido , Factores de Tiempo , Agua
3.
J Acoust Soc Am ; 120(4): 2328-39, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17069328

RESUMEN

A finite element model is formulated to study the steady-state vibration response of the anatomy of a whale (Cetacea) submerged in seawater. The anatomy was reconstructed from a combination of two-dimensional (2D) computed tomography (CT) scan images, identification of Hounsfield units with tissue types, and mapping of mechanical properties. A partial differential equation model describes the motion of the tissues within a Lagrangean framework. The computational model was applied to the study of the response of the tissues within the head of a neonate Cuvier's beaked whale Ziphius cavirostris. The characteristics of the sound stimulus was a continuous wave excitation at 3500 Hz and 180 dB re: 1 microPa received level, incident as a plane wave. We model the beaked whale tissues embedded within a volume of seawater. To account for the finite dimensions of the computational volume, we increased the damping for viscous shear stresses within the water volume, in an attempt to reduce the contribution of waves reflected from the boundaries of the computational box. The mechanical response of the tissues was simulated including: strain amplitude; dissipated power; and pressure. The tissues are not likely to suffer direct mechanical or thermal damage, within the range of parameters tested.


Asunto(s)
Acústica , Cabeza/anatomía & histología , Modelos Biológicos , Ballenas/anatomía & histología , Ballenas/fisiología , Animales , Simulación por Computador , Femenino , Cabeza/diagnóstico por imagen , Cabeza/fisiología , Presión , Agua de Mar , Sonido/efectos adversos , Tomografía Computarizada por Rayos X , Vibración
4.
Science ; 292(5517): 713-6, 2001 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-11326095

RESUMEN

Shear-wave splitting analysis of local events recorded on land and on the ocean floor in the Tonga arc and Lau backarc indicate a complex pattern of azimuthal anisotropy that cannot be explained by mantle flow coupled to the downgoing plate. These observations suggest that the direction of mantle flow rotates from convergence-parallel in the Fiji plateau to north-south beneath the Lau basin and arc-parallel beneath the Tonga arc. These results correlate with helium isotopes that map mantle flow of the Samoan plume into the Lau basin through an opening tear in the Pacific plate.

5.
J Acoust Soc Am ; 109(4): 1728-35, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11325141

RESUMEN

The acoustic calls of blue whales off California are described with visual observations of behavior and with acoustic tracking. Acoustic call data with corresponding position tracks are analyzed for five calling blue whales during one 100-min time period. Three of the five animals produced type A-B calls while two produced another call type which we refer to as type D. One of the animals producing the A-B call type was identified as male. Pauses in call production corresponded to visually observed breathing intervals. There was no apparent coordination between the calling whales. The average call source level was calculated to be 186 dB re: 1 muPa at 1 m over the 10-110-Hz band for the type B calls. On two separate days, female blue whales were observed to be silent during respective monitoring periods of 20 min and 1 h.


Asunto(s)
Vocalización Animal/fisiología , Ballenas/fisiología , Animales , Femenino , Masculino , Factores Sexuales
6.
Nature ; 408(6814): 827-32, 2000 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-11130715

RESUMEN

Knowledge of past variations in the intensity of the Earth's magnetic field provides an important constraint on models of the geodynamo. A record of absolute palaeointensity for the past 50 kyr has been compiled from archaeomagnetic and volcanic materials, and relative palaeointensities over the past 800 kyr have been obtained from sedimentary sequences. But a long-term record of geomagnetic intensity should also be carried by the thermoremanence of the oceanic crust Here we show that near-seafloor magnetic anomalies recorded over the southern East Pacific Rise are well correlated with independent estimates of geomagnetic intensity during the past 780 kyr. Moreover, the pattern of absolute palaeointensity of seafloor glass samples from the same area agrees with the well-documented dipole intensity pattern for the past 50 kyr. A comparison of palaeointensities derived from seafloor glass samples with global intensity variations thus allows us to estimate the ages of surficial lava flows in this region. The record of geomagnetic intensity preserved in the oceanic crust should provide a higher-time-resolution record of crustal accretion processes at mid-ocean ridges than has previously been obtainable.

7.
J Acoust Soc Am ; 98(2 Pt 1): 712-21, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7642810

RESUMEN

Calling blue and fin whales have been tracked using relative travel times and amplitudes from both direct and multipath arrivals to a seafloor array of seismometers. Calls of three fin whales swimming in the same general direction, but several kilometers apart, are believed to represent communication between the whales because of signature differences in call character, an alternating call pattern, and coordination of call and respiration times. Whale call tracks, call patterns, call character, and swimming speeds were examined during periods with and without the presence of noise. Noise sources included airguns, when the whales were subject to sound levels of up to 143 dB P-P (peak-to-peak) re: 1 microPa over the 10 to 60-Hz band, and transits of merchant ships, when the whales received continuous levels up to 106 dB rms re: 1 microPa over the 10 to 60-Hz band (115 dB P-P). Whale responses associated with these noises remain arguable.


Asunto(s)
Ballenas , Animales , Conducta Animal , Ecolocación , Ruido , Océano Pacífico , Espectrografía del Sonido , Vocalización Animal
8.
J Microsc ; 134(Pt 3): 245-60, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6748059

RESUMEN

The acoustic microscope is used to investigate the elastic properties of living biological cells. A quantitative model is developed relating acoustic microscope image contrast to cellular elastic properties. Cytoplasmic acoustic attenuation is measured by focusing the acoustic microscope on the surface of the underlying substrate. Cytoplasmic acoustic impedance is measured by focusing the acoustic microscope on the top surface of the cell. The model allows the acoustic microscope to give quantitative information about cellular elasticity on a subcellular scale.


Asunto(s)
Acústica , Fenómenos Fisiológicos Celulares , Microscopía/métodos , Animales , Movimiento Celular , Elasticidad , Modelos Biológicos
9.
Proc Natl Acad Sci U S A ; 78(3): 1656-60, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6940179

RESUMEN

This paper reports preliminary results of the observation by acoustic microscopy of living cells in vitro. The scanning acoustic microscope uses high-frequency sound waves to produce images with submicrometer resolution. The contrast observed in acoustic micrographs of living cells depends on the acoustic properties (i.e., density, stiffness, and attenuation) and on the topographic contour of the cell. Variation in distance separating the acoustic lens and the viewed cell also has a profound effect on the image. When the substratum is located at the focal plane, thick regions of the cell show a darkening that can be related to cellular acoustic attenuation (a function of cytoplasmic viscosity). When the top of the cell is placed near the focal plane, concentric bright and dark rings appear in the image. The location of the rings can be related to cell topography, and the ring contrast can be correlated to the stiffness and density of the cell. In addition, the character of the images of single cells varies dramatically when the substratum upon which they are grown is changed to a different material. By careful selection of the substratum, the information content of the acoustic images can be increased. Our analysis of acoustic images of actively motile cells indicates that leading lamella are less dense or stiff than the quiescent trailing processes of the cells.


Asunto(s)
Miocardio/citología , Animales , Células Cultivadas , Embrión de Pollo , Ventrículos Cardíacos/citología , Microscopía/instrumentación , Microscopía/métodos , Ultrasonido/instrumentación
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