Entry of Trypanosoma (Schizotrypanum) dionisii to macrophages in vitro and its subsequent fate therein.

Observations by phase contrast, fluorescence and electron microscopy showed that epimastigotes of Trypanosoma (Schizotrypanum) dionisii (grown in vitro) were phagocytosed posterior end first by mouse peritoneal macrophages in vitro. Many were subsequently digested as a result of phagosome-lysosome fusion but others survived by apparently inhibiting this fusion and/or escaping from the phagosome into the host cell's cytoplasm. These survivors replicated as amastigotes. Long trypomastigotes, separated from populations grown in vitro by passage down a column of glass beads (with or without prior exposure to guinea-pig serum), were phagocytosed by either pole and all were subsequently digested.     

Trypanosoma (Schizotrypanum) dionisii: effect of various agents on attachment and entry to macrophages in vitro and on morphogenesis

The attachment and entry of Trypanosoma dionisii to mouse peritoneal macrophages in vitro were studied. Both occurred to a similar extent whether parasites were alive or heat-killed, and whether macrophages were obtained from normal or immunized mice. Attachment occurred equally at 4 and 37 degrees C, but entry only occurred at the higher temperature. Neither was affected by pretreatment of parasites with active or inactivated complement. Entry, but not attachment, was inhibited by cytochalasin B; both were inhibited by trypsin. Immune mouse plasma (if inactivated) stimulated attachment but not entry (within 24 h). It also stimulated intracellular replication of T. dionisii by multiple fission and subsequent differentiation (probably within macrophages) to small extracellular trypomastigotes. No extracellular parasite and only scanty intracellular forms survived 120 h in cultures containing non-inactivated immune mouse plasma. It was concluded that attachment (in the absence of antibody) occurred to non-specific receptors in the macrophage membrane and was followed by phagocytosis of the parasites rather than their active penetration of the cell.     

An in vitro comparison of Trypanosoma spp. (subgenus Schizotrypanum) from bats

Summary Epimastigotes of Trypanosoma vespertilionis from diphasic blood agar cultures were on the average longer and the distance between the nucleus and kinetoplast greater than epimastigotes of T. hedricki, T. myoti and T. dionisii. Also, no yellow granules were seen in the epimastigotes of T. vespertilionis whereas they were obvious in the other three species. Long thin trypomastigotes which are characteristic of T. hedricki, T. myoti and T. dionisii cultures were not seen in T. vespertilionis. T. dionisii was much less infective to fibroblasts from mice and did not develop in fibroblasts from chicken, as did T. hedricki and T. myoti. Blood trypomastigotes were seen in chicken embryos inoculated with blood agar cultures of T. hedricki and T. myoti, but none was seen in embryos infected with T. dionisii.The cultural characteristics examined could not be used to differentiate T. hedricki from T. myoti. ac]19810317     

Trypanosoma (Schizotrypanum) dionisii: influence of mouse peritoneal macrophages and calf sera on extracellular growth in vitro at 37 degrees C

Macrophages and certain batches of sera were essential for extracellular multiplication of Trypanosoma dionisii in vitro in medium 199 with 20% (v/v) calf serum at 37 degrees C. In mixtures of 'good' and 'bad' batches of sera, multiplication increased as the proportion of the former was increased. Mixtures of 'bad' and 'intermediate' sera permitted virtually no growth. Phagocytosis of parasites by macrophages was unaffected by different batches of sera, though reduced in medium 199 alone. Replacement of supernatant medium by medium containing 'bad' serum reduced the macrophage infection rate no more than did transfer to medium containing 'good' serum. Daily addition of medium conditioned by prior contact with macrophages in vitro to cultures of trypanosomes without macrophages resulted in growth at least as good as that in the presence of macrophages. Extracellular replication in medium 199 at 37 degrees C apparently required at least two factors: 'M factor' provided by macrophages, but not required at 28 degrees C; and 'S+ factor' present in some batches of calf serum, essential also at 28 degrees C but not required by intracellular parasites. Some sera appeared to contain an inhibitory 'S- factor'.     

A New Liquid Medium for Trypanosoma (Schizotrypanum) cruzi*

A new liquid medium, with fetal calf serum as the sole undefined component, was devised for the cultivation of Trypanosoma cruzi. The need for the serum is ascribed to its mitogenic proteins, which stimulate division of, and the uptake of [³H]thymidine by the parasites. In the new medium, T. cruzi has a cycle culminating in the appearance of up to 90% metacyclic forms in the stationary phase. This cycle is repeated on each serial transfer.     

Eimeria pipistrellus n. sp. from Pipistrellus kuhlii (Chiroptera: Vespertilionidae) in Saudi Arabia

Fecal samples from 12 Pipistrellus kuhlii captured at Shagrah, Saudi Arabia, were examined for coccidia and three (25%) found to harbor a undescribed eimerian, herein described as Eimeria pipistrellus n. sp. Sporulated oocysts were subspherical, 24.8 x 23.2 (22-27 x 20-25) microns, with a bilayered and smooth wall. The micropyle was absent, but a large oocyst residuum and a single polar granule were present. Sporocysts were ovoid, 11.6 x 8.3 (10.5-13 x 7.5-9) microns, with a prominent Stieda body, but without a substiedal body; sporozoites lay head to tail in sporocysts and contained one large posterior refractile body. Eimeria pipistrellus n. sp. is the 3rd species of the genus Eimeria found from bats of the genus Pipistrellus.     

Evolutionary Insights from Bat Trypanosomes: Morphological, Developmental and Phylogenetic Evidence of a New Species, Trypanosoma (Schizotrypanum) erneyi sp. nov., in African Bats Closely Related to Trypanosoma (Schizotrypanum) cruzi and Allied Species

Parasites of the genus Trypanosoma are common in bats and those of the subgenus Schizotrypanum are restricted to bats throughout the world, with the exception of Trypanosoma (Schizotrypanum) cruzi that also infects other mammals and is restricted to the American Continent. We have characterized trypanosome isolates from Molossidae bats captured in Mozambique, Africa. Morphology and behaviour in culture, supported by phylogenetic inferences using SSU (small subunit) rRNA, gGAPDH (glycosomal glyceraldehyde 3-phosphate dehydrogenase) and Cyt b (cytochrome b) genes, allowed to classify the isolates as a new Schizotrypanum species named Trypanosoma (Schizotrypanum) erneyi sp. nov. This is the first report of a Schizotrypanum species from African bats cultured, characterized morphologically and biologically, and positioned in phylogenetic trees. The unprecedented finding of a new species of the subgenus Schizotrypanum from Africa that is closest related to the America-restricted Trypanosoma (Schizotrypanum) cruzi marinkellei and T. cruzi provides new insights into the origin and evolutionary history of T. cruzi and closely related bat trypanosomes. Altogether, data from our study support the hypothesis of an ancestor trypanosome parasite of bats evolving to infect other mammals, even humans, and adapted to transmission by triatomine bugs in the evolutionary history of T. cruzi in the New World.     

Genomic DNA sequence polymorphism of Trypanosoma (Schizotrypanum) cruzi isolates with phenotypic variation

1. Single-copy DNA sequences were analyzed by molecular hybridization to determine both the extent of complementarity and time of evolutionary divergence between three isolates obtained from Argentina, Mexico or Venezuela. 2. The Mexico-Venezuela pair appeared much closer than the Mexico-Argentina pair. 3. The tentative values for time of evolutionary divergence were higher than those estimated previously by allozymic variation.     

Linstowinema breve n. sp. (Nematoda: Seuratidae) a parasite of Antechinus agilis (Marsupialia: Dasyuridae) from Australia

A new echinonematine nematode, Linstowinema breve sp. n., from the small intestine of the dasyurid marsupial Anthechinus agilis is described. The species is distinguished from its congeners by the possession of the following suite of characters: small size; first and third row of cephalic hooks similar in size; second row larger; 13-15 rows of body hooks without undulating edges on the dilated cuticle of the oesophageal region; oesophagus terminating at the level of the 5th-7th row of body hooks; ten pairs of caudal papillae; a large pair of lateral ad-cloacal papillae extend into small lateral alae. Linstowinema larvae previously recorded from A. agilis may be the same species. A key to species of the genus linstowinema is provided.     

Trypanosoma (Schizotrypanum) cruzi: repetitive DNA sequence evolution in three geographically distinct isolates

1. Middle-repetitive DNA sequences were analyzed by molecular hybridization to determine both the extent of complementarity and time of evolutionary divergence between isolates of Trypanosoma cruzi from Argentina, Mexico, or Venezuela. 2. Although molecular hybridizations showed no significant difference between the middle-repetitive DNAs of the Mexican and Venezuelan isolates, there was a 2.7% base pair mismatch in hybrid molecules formed by association of strands from both the Mexican and Argentine isolates. 3. Using the rates for divergence of middle-repetitive DNA in sea urchins, the Mexican and Argentine isolates were estimated to have diverged approximately 20-25 million years ago. 4. Analysis of the kinetics for the DNA hybridizations indicates that only minor amplifications of specific gene sequences or changes in the complexity of the genomes could have occurred during the divergence of the three isolates studied.     

Tachypteron franzeni n. gen., n. sp., earliest emballonurid bat from the Middle Eocene of Messel (Mammalia, Chiroptera)

A new genus and species of emballonurid microchiropteran,Tachypteron franzeni, is described from the early Middle Eocene (MP 11) of Grube Messel, near Darmstadt, Germany. The holotype is extraordinarily well-preserved. It is the first unequivocal representative of an extant clade among Messel bats and the oldest unequivocal record of Emballonuridae. The flight apparatus ofT. franzeni is highly specialized for a rapid and constant flight style. The proportions of the strikingly narrow wing, the outline of the flight membranes and external ear, the morphology of the postcranial skeleton, and the relative cochlea size ofT. franzeni and extantTaphozous species are almost identical, while the dentition ofT. franzeni is distinguished by more plesiomorphic features.Tachypteron and the fairly diverse Paleogene record of emballonurids from France, consisting mainly of isolated teeth, document the earliest radiation known from an extant bat family and suggest a rather intense pre-Middle Eocene diversification of emballonurids.     

Lindernia ciliata subsp. sivarajanii subsp. nov. (Scrophulariaceae) from India

A new subspecies of Lindernia ciliata (Colsm.) Pennell is described and illustrated. Lindernia ciliata (Colsm.) Pennell subsp. sivarajanii Dhruvan et Mohanan differs from L. ciliata subsp. ciliata by its creeping habit, rooting from almost all nodes, distant and sub‐aristate leaf serrations, upper lip of corolla almost equal in length to the lower lip and straight staminodes.     

Crocus antalyensis subsp. striatus subsp. nov. (Iridaceae) from southwest Anatolia

A new subspecies Crocus antalyensis subsp. striatus subsp. nov. from western Turkey is described. It is characterized by rough papery, light brown corm tunics, leaves that exceed the flower at anthesis and are recurved, distinctly striped inner perianth segments and deeply branched pale yellow or white style. The karyotype of the new subspecies is presented.