The components of MS (obesity, hypertension, and dyslipidaemia) are associated with the presence of NASH in patients with CH-B. The presence of hepatic fibrosis seems to be associated with known host and viral factors as well as the presence of abdominal obesity.

We have imaged gold-labeled DNA molecules with the atomic force microscope (AFM). Circular plasmid DNA was labeled at internal positions by nick-translation using biotinylated dUTP. For visualization, the biotinylated DNA was linked to streptavidin-coated colloidal gold spheres (nominally 5 nm diam) prior to AFM imaging. Reproducible images of the labeled DNA were obtained both in dry air and under propanol. Height measurements of the DNA and colloidal gold made under both conditions are presented. The stability of the DNA-streptavidin colloidal gold complexes observed even under propanol suggests that this labeling procedure could be exploited to map regions of interest in chromosomal DNA.

Polytene chromosomes from the salivary gland cells of Drosophila melanogaster were examined by atomic force microscopy. The atomic force microscope (AFM) was capable of resolving chromosomal features down to the limits of the tip sharpness, about 500 A for pyramidal-shaped tips. Resolution was increased to 300 A by using electron beam deposited (EBD) tips with high aspect ratios. This significantly exceeds the resolution obtainable with conventional optical microscopes, but at the cost of compromising the structural integrity of the sample. A reasonable compromise was achieved by using oxide-sharpened tips. In this case high resolution was obtained without sample degradation, but when desired these tips were also capable of sample disintegration with increased scanning force and rate. Thus, oxide-sharpened tips were used to precisely dissect defined chromosomal regions to illustrate their potential use in genetic mapping efforts. This study illustrates the utility of the AFM in the characterization and manipulation of chromosomes and chromosomal DNA.

An ovarian mixed germ cell tumor in a 34-year-old woman contained a predominant component of polyembryoma as well as foci of choriocarcinoma, yolk sac tumor, and immature teratoma. No previous cases of identical composition have been found in the literature.

The application of atomic force microscopy (AFM) to biological investigation is attractive for a number of reasons. Foremost among these is the ability of the AFM to image samples, even living cells, under near native conditions and at resolution equal to, or exceeding, that possible by the best light microscopes. Moreover, the ability of the AFM to manipulate samples it images provides a novel and far reaching application of this technology.We have been studying a number of biological samples by AFM. These include conventional and non-conventional nucleic acid structures, ribosomes, neural cells and synapses, cellular organelles (chloroplasts and nuclei), among others. Each of these projects has its own set of associated difficulties and each reveals information about the uses and limits of the AFM in biology. Fig. 1 shows AFM images of various biological samples. In the case of nucleic acids, which have been extensively studied in a number of labs by AFM the problems of signal/noise sample deposition have been overcome in air and organic solvents.