Behaviour of the Talapoin monkey (Miopithecus talapoin) studied in groups, in the laboratory

The behaviour of the Talapoin monkey has been studied both qualitatively and quantitatively by observing small captive groups kept in the laboratory. The behavioural repertoire is compared with that of other Old World Catarrhines. Talapoins show greater similarities to Cercopithecus monkeys than to Erythrocebus, Macaca, Papio or Cercocebus . However, there are differences in behaviour between talapoins and Cercopithecus monkeys, which lend additional support to the view that the former should be placed in the separate genus Miopithecus .     

Studies on the Attachment of Leishmania Flagella to Sand Fly Midgut Epithelium

An in vitro assay was developed to study the recognition mechanism for attachment of Leishmania flagella to sand fly midgut epithelium. Frozen sections of sand fly guts were incubated with Hagella preparations, and probed with a flagella-specific monoclonal antibody. Tissue-specific adhesion of flagella to midgut epithelium was demonstrated by indirect immunofluorescence. None of the 13 sugars, screened to test for possible lectin-mediation, appeared to significantly inhibit the adhesion of flagella to gut sections. Similarly no inhibition was achieved by incubating flagella with pep 63 which inhibits the promastigote-macrophage recognition mechanism. Significant inhibition was attained by incubating flagella preparations with a monoclonal antibody which binds to a flagellar membrane-component. The possible relevance of the described mechanism for the biology of Leishmania in their sand fly hosts, is discussed.     

Bile salts of fishes collected on the Zaire River Expedition (1974-5): their chemical nature and its possible significance

Bile salts from 21 fish species caught during the Zaïre River Expedition (1974–5) have received partial or complete chemical analysis. Conclusions from the results are as follow. (1) Polypterus bile salts are biochemically advanced, but with easily detectable features regarded as relicts from ancestral stock. The bile acids include haemulcholic acid, previously found only in a marine teleost and an unidentified acid also found in a mormyrid. (2) This mormyrid has advanced bile salts, consisting almost entirely of taurine conjugates of haemulcholic acid (present in Polypterus) , and two other C₂₄ acids. (3) Three Alestes and three Distichodus species have no more than traces of primitive bile salts; their bile acids suggest a degree of activity of intestinal microorganisms during the enterohepatic circulation not previously noticed in fishes. (4) The predatory Hydrocynus has bile acids of an omnivorous rather than a carnivorous type. (5) The Barbus species have primitive bile salts closely similar to those of Cyprinidae previously examined but containing also (in two species) a newly-discovered bile alcohol sulphate: in contrast, a Varicorhinus does not have this new substance and has a chief bile salt found so far only as a minor constituent in the Cyprinidae. (6) Two Labeo species are different from all other cyprinids examined: diey both have a new major bile alcohol sulphate. (7) Four Siluriformes show evidence of enterohepatic changes that might be characteristic of some tropical freshwater fish; three have taurine-conjugated haemulcholic acid. (8) Synodontis species are remarkable in having a high proportion of unconjugated bile acid ions and this finding was confirmed with fresh material.     

A Fluid System for the Cultivation,Light Microscope Examination and Manipulation of Obligate Anaerobes*

A chamber in tandem with oxygen-free gas supply and gas-collecting reservoirs constitutes a system capable of anaerobic maintenance within the range of 0.8–20 μM at 13 C. Cultures contained within the chamber portion of this system are examined through exposed oculars of a microscope otherwise sealed from room atmosphere. Materials are interchanged between the 2 atmospheres through an air lock. Shoulder-length gloves enable all manipulations common to aerobic cultivation procedures without undue restraint.     

Abundance and survival of a seed-infesting weevil, Pseudanthonomus hamamelidis (Coleoptera: Curculionidae), on its variable-fruiting host plant, witch-hazel (Hamamelis virginiana)

Abstract. 1. The relative importance of seed abundance and of mortality factors in the population biology of Pseudanthonomus hamamelidis , a hostspecific predispersal seed predator on Hamamelis virginiana , is evaluated by analysis of weevil life tables and abundance estimates in three years with markedly different magnitudes of fruit production.
2. Fruit production of marked Hamamelis individuals averaged 336 m^-2 in 1978, increased three- to four-fold in 1979, and declined again in 1980. More individuals fruited in 1979 than in the other two years.
3. The early larval stage of P.hamamelidis incurred the greatest mortality, with 42–58% dying from often undeterminable causes. Losses in the egg stage ranged from 22% to 31%. Three parasitoid species each accounted for minor mortality. Generation survival was similar in all three years, ranging from 21% to 28%.
4. The percentage of Hamamelis fruit crops infested by P.hamamelidis was high in 1978, averaging 76%, but was much lower in 1979, the year of abundant fruit. In 1980, when fruit were less abundant again, infestation was nearly complete. Egg densities on fruits were lower in 1979 than in the other two years.
5. The fluctuating fruit crops of Hamamelis are responsible for limitation of P.hamamelidis numbers during poor fruiting years. The occasional highly productive fruiting year results in satiation of weevil populations and concomitant seed escape by Hamamelis . Mortality factors appear less important in influencing weevil population dynamics.     

I. Extracellular Cultivation and Morphological Characterization of Amastigote-Like Forms of Leishmania panamensis and L. braziliensis

. Two strains of the Leishmania braziliensis complex have been adapted to grow extracellularly at elevated temperature as amastigote-like forms in a cell-free medium. These parasites can be serially cultivated and maintained at 32°C for L. panamensis (WR442; L. braziliensis panamensis ) and at 28°C for L. braziliensis (M5052; L. braziliensis braziliensis ). Several observations are presented that the forms adapted at elevated temperature are amastigote-like. Morphologically, the amastigote-like organisms appear rounded to ovoid and are immotile and smaller than promastigotes; the flagellum of the amastigote-like forms does not extend beyond the flagellar pocket. In comparison, the promastigotes are very elongated, with a nucleus at mid-cell length and a very long flagellum. By electron microscopy, the short flagellum of the amastigote-like form is within a distended flagellar pocket; the 9 + 2 axonemal configuration is present but the paraxial rod is not observed. By contrast, the flagellum of the promastigote has a paraxial rod which extends from the axosome level. In addition, these amastigote-like forms of Leishmania are able to infect, to survive and to divide within the macrophage cell line J774.     

Metabolism of 3-indoleacetic acid in tobacco exposed to the air pollutant peroxyacetyl nitrate

The influence of an air pollutant, peroxyacetyl nitrate (PAN),on 3-indoleacetic acid (IAA) and its metabolites in tobaccoplants was studied. Plants were administered IAA-2-¹⁴C immediatelybefore or after gassing with PAN. After 8 hr metabolism in thedark or in the light the plants were separated into shoot tipand damaged and undamaged leaf areas prior to analysis. PAN-treatedplants which metabolized in the light and produced partiallydamaged leaves showed a relative increase in unmetabolized IAAin the leaves compared to control treatments. Several suspectedindole conjugates from leaves of PAN-treated plants containedrelatively less label than controls. Plants which metabolizedin the dark and showed no visible external damage also demonstratedchanges in indoleacetic acid metabolism. The changes were qualitativelydifferent however from those observed in damaged tissue. UndamagedPAN-treated tissue consistently had less of certain unidentifiedcompounds. It was concluded that PAN is capable of causing biochemicallesions in indole metabolism prior to the expression of visibledamage. ¹ Present address: Canada department of Agriculture, ResearchBranch, 2560 Chemin Gomin, Ste-Foy, Quebec 10, Canada. (Received June 29, 1971; )     

Developmental Life Cycle of Leishmania—Cultivation and Characterization of Cultured Extracellular Amastigotes1

ABSTRACT. The biochemistry and immunology of Leishmania promastigotes has been extensively studied; this is due primarily to the facility with which this stage, in contrast to the amastigotes stage, can be maintained in axenic culture. Several attempts to axenically culture lines of Leishmania amastigotes have been reported in the literature. This paper summarizes methods of adaptation (low pH, elevated temperature and culture medium) and characterization of several axenic lines of Leishmania amastigotes. Based on morphological, biological, immunological and biochemical evidence, these organisms appear to resemble amastigotes from infected macrophages or tissue. The axenically cultured amastigotes appear to be distinct from shocked (heat, serum deprivation, stressed) Leishmania promastigotes in the plethora of proteins synthesized, growth (multiplication) in culture, and developmental regulation observed. These data suggest that Leishmania organisms have a significant developmental response to certain signals (pH, temperature) mimicking their in vivo macrophage milieu. The response to other environmental parameters characteristic of the host-macrophage remain to be determined. These axenically cultured amastigotes should be of interest for further immunological, biochemical and developmental investigations of the disease-maintaining stage of this parasite.