The presence of a smooth contour, round shape, and capsule is highly suggestive of a type A tumor. Foci of low signal intensity in the mass on T2-weighted images and mediastinal lymphadenopathy are highly suggestive of thymic carcinomas.

UIP has a characteristic appearance that usually facilitates distinction from other types of chronic IIPs at thin-section CT. The most useful finding when differentiating UIP from NSIP was the extent of honeycombing.

BackgroundLower muscle density on computed tomography (CT) provides a measure of fatty infiltration of muscle, an aspect of muscle quality that has been associated with metabolic abnormalities, weakness, decreased mobility, and increased fracture risk in older adults. We assessed the cross-sectional relationship between HIV serostatus, age, thigh muscle attenuation, and thigh muscle cross-sectional area (CSA).MethodsMean CT-quantified Hounsfield units (HU) of the thigh muscle bundle and CSA were evaluated in 368 HIV-infected and 145 HIV-uninfected men enrolled in the Multicenter AIDS Cohort Study (MACS) Cardiovascular Substudy using multivariable linear regression. Models all were adjusted for HIV serostatus, age, race, and body mass index (BMI); each model was further adjusted for covariates that differed by HIV serostatus, including insulin resistance, hepatitis C, malignancy, smoking, alcohol use, and self-reported limitation in physical activity.ResultsHIV-infected men had greater thigh muscle CSA (p<0.001) but lower muscle density (p<0.001) compared to HIV-uninfected men. Muscle density remained lower in HIV-infected men (p = 0.001) when abdominal visceral adiposity, and thigh subcutaneous adipose tissue area were substituted for BMI in a multivariable model. Muscle density decreased by 0.16 HU per year (p<0.001) of increasing age among the HIV-infected men, but not in the HIV-uninfected men (HIV x age interaction -0.20 HU; p = 0.002).ConclusionHIV-infected men had lower thigh muscle density compared to HIV-uninfected men, and a more pronounced decline with increasing age, indicative of greater fatty infiltration. These findings suggest that lower muscle quality among HIV-infected persons may be a risk factor for impairments in physical function with aging.

No abstract

Abstract. Transforming growth factor beta 1 (TGF-ß1) is a proposed regulator of Ids (inhibitors of DNA binding/differentiation) gene expression in epithelial cells. We previously reported that Id proteins are variously expressed in human hepatocellular carcinomas (HCC). However, the mechanism of regulation of Ids in HCC remains obscure. Here, we examined the relationship between Id1 and TGF-ß1 in four HCC cell lines, and studied the changes in cell proliferation, cell cycle and differentiation. The four HCC cell lines expressed Id1, TGF-ß1 and their receptors at various levels. TGF-ß1 strongly inhibited the growth of HuH7 cells, while the growth inhibition was moderate in PLC/PRF/5, and was not observed in HLE and HLF cell lines. TGF-ß1-induced growth inhibition in HuH7 cells was associated with cell accumulation in the G1 phase and partial induction of differentiation (with reduction of AFP and AFP-L3). Induction by TGF-ß1 dose-dependently suppressed Id1 expression in HuH7 cells; 1 ng/ml TGF-ß1 inhibited Id1 by 84.0 and 78.6% that of the untreated control at transcriptional and protein levels, respectively. HLE and HLF cells, which did not exhibit a TGF-ß1 growth inhibitory effect, lacked TGF-ß receptors and Id1 expression was not altered. In PLC/PRF/ 5 cells, Id1 augmentation was not observed in response to TGF-ß1, indicating that TGF-ß1-induced growth inhibition was not related to Id1 in this cell line. Our results suggest that, in some HCC cells, the pathway of suppression of Id1 by TGF-ß1 may be important in TGF-ß1-induced growth inhibition and partial differentiation.