The causative agent of cutaneous leishmaniasis in Mauritania is identified for the first time as Leishmania major MON-117, a new zymodeme closely related to MON-26. The authors point out the need to study this previously unknown focus.
The causative agent of cutaneous leishmaniasis in Mauritania is identified for the first time as Leishmania major MON-117, a new zymodeme closely related to MON-26. The authors point out the need to study this previously unknown focus.
When inoculated subcutaneously, the infective larvae of L. sigmodontis undergo complete development and produce a patent microfilaraemia in mice of the BALB background (BALB/c, BALB/K and BALB/B, with respectively the H-2d, H-2k et H-2b haplotypes). The most susceptible strain is BALB/c with all mice harbouring adult filariae and 47% of mice presenting with a patent microfilaraemia. Mice with the B10 background (B10, B10Br and B10D2, with respectively the H-2b, H-2k et H-2d haplotypes) are almost completely resistant to infection. Adult filariae were recovered from all mice of the CBA/Ca, CBA/HN, C3H/HeN, DBA/2N strains. However, the site and structural development of the parasite varied in each strain. Absence of microfilaraemia is associated with absent or abnormal spicules, reduced number of female filariae and small size of female filariae. These results show that the Major Histocompatibility Complex only modulates the developmental pattern of filariae within the limits imposed by background genes. Male CBA/HN and C3H/HeN were more susceptible to infection than female mice. Inverse phenomenon was observed with strains BALB/c; and, no host sex effect was seen in DBA/D2N.
The tick species commonly collected at the Northeast of Spain are reported in this paper. Data on hosts, temperature and humidity requirements, vegetation relationships, altitudinal distribution, and seasonal activity are included. R. sanguineus is commonly collected in areas with Mediterranean vegetation, esteppe, and semi-desertic esteppe, ranging from 190 to 1,000 meters above the sea level. R. sanguineus is related with sparse vegetal areas, and it is absent from areas with dense shrub or forests of every kind; sometimes, small populations may be collected in ecotones between Pinus spp. and esteppe formations. R. pusillus is closely related to areas of Mesomediterranean vegetation, sometimes subordinate to Pinus spp. and Quercus spp. The climate to which the species ally is always of continental type, with a hot and dry summer, and cold winter; although the species is commonly restricted to its main host, Oryctolagus cuniculus, several specimens have been collected from V. vulpes. Our data display the clear affinity of I. ricinus to the Supramediterranean vegetation (Aceri-Quercion faginae), places of Quercetum-Buxetum, as well as the Iberian Oromediterranean vegetation (Pinus sylvestris-Buxus sempervirens). Captures are scarce in forest of Fagus sylvatica, but data suggest that the species may be locally common on such places. Climate for the zones of collection of I. ricinus is Atlantic attenuated, with mild summers and humid winters. D. marginatus is strongly related to the xerophilic vegetation, widely spread through the Mediterranean, Supramediterranean, and hill levels, but does not colonize the true Oromediterranean vegetation. In our captures, the species is commonly collected in pubescent oak formations, but it does not penetrate in true forest associations.(ABSTRACT TRUNCATED AT 250 WORDS)
Three groups of 4 cattle have been vaccinated with either detergent solubilized tick tissue proteins (SMP) of male and female Rhipicephalus appendiculatus, a 20 kDa soluble integumental antigen, a mixture of both SMP and 20 kDa. Two weeks after one booster injection all cattle were challenged by infestation with adult ticks. Treatment had no influence on tick attachment but on cattle vaccinated by the 20 kDa 32.5% fed ticks died (p < 0.001). Moreover, the mean weight of ticks fed on 7 out of 12 vaccinated cattle was significantly lower (p < 0.05 to p < 0.001). Individual differences could be seen where the mean weight reduction was up to 30%. Moreover, ticks fed on 1 (group SMP) or 2 cattle (group 20 kDa) had some difficulties in converting their blood meal into eggs (p < 0.05 to p < 0.001).
The antimalarial activity of the fatty alcohol, n-hentriacontanol, isolated from the bolivian Solanaceae, Cuatresia sp, is investigated in vivo through a classical four-day suppressive test against Plasmodium berghei and P. vinckei in mice. This product markedly reduced the virulence of experimentally induced P. vinckei infection. n-Hentriacontanol belongs to a new class of antimalarial natural compounds to be exploited for therapeutic purposes.