Effects of ozone and sulfur dioxide on phyllosphere fungi from three tree species.

Short-term effects of ozone (O(3)) on phyllosphere fungi were studied by examining fungal populations from leaves of giant sequoia (Sequoiadendron giganteum (Lindl.) Buchholz) and California black oak (Quercus kelloggii Newb.). Chronic effects of both O(3) and sulfur dioxide (SO(2)) were studied by isolating fungi from leaves of mature Valencia orange (Citrus sinensis L.) trees. In this chronic-exposure experiment, mature orange trees were fumigated in open-top chambers at the University of California, Riverside, for 4 years with filtered air, ambient air plus filtered air (1:1), ambient air, or filtered air plus SO(2) at 9.3 parts per hundred million. Populations of Alternaria alternata (Fr.) Keissler and Cladosporium cladosporioides (Fres.) de Vries, two of the four most common fungi isolated from orange leaves, were significantly reduced by chronic exposure to ambient air. In the short-term experiments, seedlings of giant sequoia or California black oak were fumigated in open-top chambers in Sequoia National Park for 9 to 11 weeks with filtered air, ambient air, or ambient air plus O(3). These short-term fumigations did not significantly affect the numbers of phyllosphere fungi. Exposure of Valencia orange trees to SO(2) at 9.3 parts per hundred million for 4 years reduced the number of phyllosphere fungi isolated by 75% compared with the number from the filtered-air treatment and reduced the Simpson diversity index value from 3.3 to 2.5. A significant chamber effect was evident since leaves of giant sequoia and California black oak located outside of chambers had more phyllosphere fungi than did seedlings within chambers. Results suggest that chronic exposure to ambient ozone or SO(2) in polluted areas can affect phyllosphere fungal communities, while short-term exposures may not significantly disturb phyllosphere fungi.

Identification of human T cell leukemia virus in a Japanese patient with adult T cell leukemia and cutaneous lymphomatous vasculitis.

We have identified a Japanese patient with adult T-cell leukemia (ATL) whose T cells in vitro produced the human T-cell leukemia virus (HTLV). This patient presented with lymphomatous arthritis and leukemia and subsequently developed skin lesions. Skin invasion by malignant T-cells was angiocentric and produced vessel wall destruction, resulting in necrotic cutaneous tumor nodules. Malignant T cells in peripheral blood, skin, and joint prior to culture in vitro did not express p19 HTLV-associated antigen. However, by electron microscopy, intracellular type C viral particles were seen in skin-infiltrating T cells. Peripheral blood malignant cells after 7 days in culture with T-cell growth factor-supplemented media expressed p19 antigen, and type C virus particles were seen by electron microscopy to be budding from malignant T lymphocytes. Mitomycin-C-treated peripheral-blood T cells induced the transformation of cord blood T cells into HTLV-infected p19+ T cells. The demonstration of HTLV in malignant T cells from our patient confirms the association of HTLV with Japanese adult T-cell leukemia. Moreover, HTLV may be associated with a vasculitis-arthritis syndrome.