New epidemiological features on animal trypanosomiasis by molecular analysis in the pastoral zone of Sideradougou, Burkina Faso

A multidisciplinary work was undertaken in the agropastoral zone of Sidéradougou, Burkina Faso to try to elucidate the key factors determining the presence of tsetse flies. In this study the PCR was used to characterize trypanosomes infecting the vector ( Glossina tachinoides and Glossina palpalis gambiensis ) and the host, i.e. cattle. A 2-year survey involved dissecting 2211 tsetse of the two Glossina species. A total of 298 parasitologically infected tsetse were analysed by PCR. Trypanosoma vivax was the most frequently identified trypanosome followed by the savannah type of T. congolense and, to a lesser extent, the riverine forest type of T. congolense , and by T. brucei . No cases of T. simiae were found. From the 107 identified infections in cattle, the taxa were the same, but T. congolense savannah type was more frequent, whereas T. vivax and T. congolense riverine forest types were found less frequently. A correlation was found between midgut infection rates of tsetse, nonidentified infections and reptile bloodmeals. These rates were higher in G.p. gambiensis , and in the western part of the study area. T. vivax infections were related to cattle bloodmeals, and were more frequent in G. tachinoides and in the eastern study area. The PCR results combined with bloodmeal analysis helped us to establish the relationships between the vector and the host, to assess the trypanosome challenge in the two parts of the area, to elucidate the differences between the two types of T. congolense , and to suspect that most midgut infections were originating from reptilian trypanosomes.     

Fruit morphology in Tragopogon L. (Compositae: Lactuceae) from the Iberian Peninsula

Achenes of all the Tragopogon species from the Iberian Peninsula were examined by means of scanning-electron microscopy and stereomicroscopy. The achenes of the eight species are described, illustrated and compared. The results are contrasted with the systematics of this genus. The isolated position of T. lamottei with regard to the other seven species is noted. A key is provided to enable the different species to be distinguished.     

A 35-kDa polypeptide of the crystalline lens in the common frog: its biochemical properties, tissue specificity and appearance in the developmental process

The vertebrate lens contains so-called taxon-specific water-soluble proteins. One of them is p-crystallin with a molecular weight of 35 kDa characteristic of Ranidae family. We have identified a polypeptide with a molecular weight of 35 kDa in the eye lens of Rana temporaria which: (1) can be extracted from the lens by aqueous salt solutions, (2) has a molecular mass of 36.1 +/- 0.4 kDa (by SDS-electrophoresis) and 37 kDa (by gel filtration), (3) is heterogeneous in terms of isoelectric point (pI 6.5-8.0), (4) binds to heparin-agarose, (5) denatures in response to freezing-thawing, lyophilization and in solutions with low ionic strength. Thus, major biochemical parameters of this polypeptide differ from that of amphibian alpha, beta- and gamma-crystallins. In addition to lens, 35 kDa polypeptide was detected by immunoelectroblotting in retina, testes, liver, kidney, spleen, stomach, intestine and lungs. Its level (as percentage of water-soluble protein) is 1.1 +/- 1.4% in the lens, 1.6 +/- 0.7% in retina. 0.05% in testes and liver and 0.01% or less in other organs. Thus, despite its wide tissue distribution, 53 kDa polypeptide is expressed predominantly in lens and retina. We studied the time-course of appearance and accumulation of this polypeptide in tissues where it is expressed at high or low levels. 35 kDa polypeptide was detected for the first time during larval development: (1) in the lens (some time after the mouth opening; stages 33-34 according to Dabagian and Sleptsova, 1975), (2) in the retina (by the time of anus opening; stages 36-37), (3) in the liver (at the stage of elongated hind limb bud; stages 40-41). Definitive expression level of this protein was achieved in the lens by the beginning of metamorphosis and in the retina and liver during first months of development. Hence, during the whole period of larval development 35 kDa polypeptide content of the lens exceeds that of retina or liver. A more substantial evidence is required to confirm the identity of studied polypeptide with rho-crystallin.