Granulite-facies garnet-bearing metapelites, metabasics and calc-silicate rocks from the lower metamorphic complex (Kharta Gneiss) of the Greater Himalayan Crystallines in the Kharta region of S Tibet, E Himalaya, preserve textural and chemical evidence for prograde equilibration at temperatures of at least 700-720degreesC and pressures around 8 kbar during the main event of the Himalayan metamorphism. Post-deformational reaction textures include clinopyroxene (+/- orthopyroxene) - plagioclase symplectites after garnet in calc-silicate rocks, and cordierite +/- spinel coronas on sillimanite and garnet in metapelite granulites. These assemblages indicate a decompressional pressure-temperature path that is confirmed by the geothermobarometry of zoned and symplectite minerals as well as by calculated phase equilibria. Isothermal decompression through ca. 3 kbar occurred at temperatures of about 700degreesC, and was followed by further decompression to P similar to 3 kbar, and T similar to 710degreesC. At this point, decompression was replaced by quasi-isobaric cooling ending in the andalusite stability field at P ca. 2.5 kbar. The P-T path of the Kharta Gneiss appears to be similar to those inferred for the lower Greater Himalayan Crystallines exposed in the nearby Dudh Kosi and middle Arun valleys of eastern Nepal. This type of clockwise P-T path, with most of the exhumation occurring at relatively constant metamorphic temperatures, requires a high exhumation rate and suggests that extrusion tectonics of crustal-scale wedges may have been operative during post-collisional exhumation of the Greater Himalayan Crystallines.

Multielemental X-ray maps collected by a remote scanning system of the electron beam are processed by a dedicated software program performing accurate modal determination of geological samples. The classification of different mineral phases is based on elemental concentrations. The software program Petromod loads the maps into a database and computes a matrix consisting of numerical values proportional to the elemental concentrations. After an initial calibration, the program can perform the chemical composition calculated on the basis of a fixed number of oxygens for a selected area. In this way, it is possible to identify all the mineral phases occurring in the sample. Up to three elements can be selected to calculate the modal percentage of the identified mineral. An automated routine scans the whole set of maps and assigns each pixel that satisfies the imposed requirements to the selected phase. Repeating this procedure for every mineral phase occurring in the mapped area, a modal distribution of the rock-forming minerals can be performed. The final output consists of a digitized image, which can be further analyzed by common image analysis software, and a table containing the calculated modal percentages. The method is here applied to a volcanic and a metamorphic rock sample.

Background: Mucosis fungoides (MF) is a skin malignancy of T helper lymphocytes with a wide clinical spectrum. Among the atypical variants of MF, there is an ichthyosis-like presentation. However, to date, only 1 case of ichthyosiform MF has been reported. Objective: Our goal was to summarize the clinical characteristics and course, and the pathological, immunohistochemical and molecular genetic findings on 4 patients with ichthyosiform MF. Methods: A retrospective study was conducted. Results:The 4 patients represented 1.8% of the 221 patients with MF seen by us since 1975. None progressed to systemic disease in up to 12 years (median, 10 years) after the onset of the cutaneous manifestations. Interestingly, skin lesions typical of so-called follicular MF (FMF) were associated in 3 of 4 cases, whereas cutaneous manifestations of classic MF were absent in all 4 patients. Conclusion: Ichthyosiform MF represents a rare variant within the clinicopathologic spectrum of MF usually featuring a benign course and a tendency to be associated with lesions of FMF but not with lesions of classic IVIF. Copyright (C) 2002 S. Karger AG, Basel

Although the etiology of pulmonary fistulas in congenital heart disease remains unknown, several hemodynamic factors are thought to play a role. Recently it was postulated that hepatic venous effluent might protect the pulmonary bed from development of pulmonary fistulas. However, there are no experimental data supporting this hypothesis. Here, we present the cases of 2 patients in whom pulmonary fistulas developed after unintentional surgical exclusion of the hepatic venous flow from the pulmonary circulation. In both patients, symptoms resolved after rerouting of the hepatic venous blood to the lungs. (C) 2001 by The Society of Thoracic Surgeons.