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Abstract. Despite extensive efforts, little progress has been made in identifying the factors that induce hepatic fibrosis. Transforming growth factor-/3 (TGF-/3) has been shown to enhance collagen production, therefore its role in hepatic fibrosis was investigated. Treatment of cultured hepatic ceils with TGF-31 increased type I procollagen mRNA levels 13-fold due to posttranscriptional gene regulation. When two animal models of hepatic fibrosis, murine schistosomiasis and CC14-treated rats, were examined, they both exhibited increased levels of TGF-31 gene expression at times that somewhat preceded the increase in collagen synthesis. In contrast, in murine schistosomiasis, mRNA levels of tumor necrosis factor and interleukin-I peaked early in the fibrogenic process. Immunohistochemical analysis showed TGF-31 to be present in normal mouse liver and to be markedly increased in mice infected with schistosomiasis. TGF-31 appeared in the'hepatic parenchyma, primarily in hepatocytes. These findings strongly suggest a role for TGF-31 in a pathophysiological state.

ABSTRACT:In high-field proton NMR, the signal-to-noise ratio SNR achieved with a ( ) close-fitting solenoidal microcoil is adversely affected by radio frequency RF losses in the coil, its leads, the capacitor used to tune it, and finally, the sample. In Part II, a rigorous description of these various losses is presented, and their severity is related to the details of coil design. Results not only provide a rational basis for defining a microcoil's optimal wire diameter and the number of turns, but also for evaluating how the SNR varies with coil size and NMR frequency in high-field proton NMR studies involving either conducting or non-conducting samples. ᮊ

It is shown that high-resolution 1 H NMR spectra of intact excised tissues and organs can be obtained by rotating the sample slowly about an axis at the magic angle of 54°44 with the external magnetic field. In this way tissue and cellular damage invoked by standard magic angle spinning (MAS) experiments, where spinning speeds of several kHz are typically employed, are minimized. Special RF pulse sequences, developed originally in solid state NMR, can be used to produce a spinning sideband-free isotropic spectrum. In this article the first results are shown of the brain, heart, liver, gluteus muscle, and kidney excised from mice using the 2D-phase-altered spinning sidebands (PASS) technique and employing MAS spinning speeds of 43-125 Hz. It was found that with slow sample spinning similar, and in some cases even better, spectral resolutions are obtained as compared with fast MAS. Magn Reson Med 46: 213-218,

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