First report of filarial nematodes in free-living pitheciid primates

Although little studied, infections with nematodes of the Onchocercidae Leiper, 1911, predominated by the genera Dipetalonema Diesing, 1861 and Mansonella Faust, 1929, are frequent in wild primates and human populations in the Neotropical forest areas. This study reports natural infections with Dipetalonema freitasi Bain, Diagne & Muller, 1987 and D. gracile (Rudolphi, 1809) in two free-living species of pitheciid primates, extending the known geographical distribution of these species to the forest of the Peruvian Amazon. Adult worms were recovered from the thoracic and abdominal cavities of two species of monkeys, Pithecia monachus monachus (É. Geoffroy Saint-Hilaire) and Cacajao calvus ucayalii (Thomas) (Primates: Pitheciidae), collected along the Yavari-Mirin River basin and analysed via light and scanning electron microscopy. Both host species represent new host records for D. freitasi and D. gracile. Morphometric data are also presented for the sampled filarial worms in addition to morphological details obtained through light and electron microscopy examination of D. freitasi specimens.

     

High resolution analysis of cell cycle-correlated vimentin expression in asynchronously grown,TPA-treated MPC-11 cells by the novel flow cytometric multiparameter BrdU-hoechst/PI and immunolabeling technique

High resolution, multiparameter analysis using the flow cytometric BrdU/Hoechst quenching technique has been applied to study cell cycle kinetics and vimentin expression in individual cells of asynchronously grown MPC-11 mouse plasmacytoma cell cultures treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) to induce in vitro differentiation. BrdU treatment up to 16 h in the absence or presence of TPA did not affect either cell cycle progression or the kinetics or quantity of vimentin expression. TPA-treated cells became arrested in G1 phase of the second cell cycle; however, this G1 phase arrest was transient only. In addition, G1 phase cells located prior to a putative transition point at the beginning of TPA treatment were completely blocked in cell cycle progression. There is also evidence that cells located in G1 or G2/M phase at the beginning of TPA treatment finally expressed low levels of vimentin. On the contrary, cells located in S phase at TPA exposure showed high vimentin levels after treatment. The results presented here show that, with the flow cytometric BrdU/Hoechst quenching technique, one can correlate time-dependent protein expression at the single cell level in asynchronously grown cultures not only with the actual cell cycle state, but also with the history of cell replication. © 1994 Wiley-Liss, Inc.