摘要:

SYNOPSIS.An account of the culture methods for axenic growth ofEntamoeba histolyticais given. Three media, including Diamond's medium, have been reliable. At present 6 strains are maintained axenically; details of isolation and axenization are outlined. Growth characteristics and oxygen requirements of 2 strains are examined.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02147.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.The structure and cytochemistry of encystment and excystment ofBlepharisma stolteiIsquith are described.The encystment process may be subdivided into 4 stages: (i) in the precystic stage the buccal apparatus overlaps about the posterior, (ii) in early encystment, the buccal apparatus is resorbed and an ectocyst is secreted, (iii) an interwall space, endocyst, and plug are secreted during late encystment, and (iv) the resting cyst stage typically has disc‐like structures on the ectocyst, and a vacuole in the macronucleus.In excystment, 6 distinct stages may be defined: (i) partial kineties are formed in early excystment, (ii) permanent kineties give rise to anlagen of the buccal apparatus during stomatogenesis, (iii) the organism elongates and reforms the vegetative shape in late excystment, (iv) some cysts then divide, (v) the redeveloped organism is liberated thru the plug pore, and (vi) the postcystic stage resembles the vegetative form except for its size and lack of pigmentation.Cortical structures, extracellular membranes, and the macronuclear membrane are composed of protein‐lipids. Unbound protein and RNA are found in the cytoplasm thruout the cystic cycle. DNA is present only in the nuclei. Polysaccharides, 1st found in the cytoplasm, are shifted to the plug in encystment. The plug material disappears during excystment, while PAS positive granules appear in the cytopl

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02148.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.Male production in the M5 strain ofVolvox aureusis controlled by a diffusible hormone. A new strain ofV. aureus, DS, is described whose control mechanism for male production is deficient. DS forms males very rarely despite production of a fully functional male‐inducing hormone, M5 colonies serving as testers. The DS and M5 hormones were both non‐dialyzable, and both were>50% inactivated when kept at 60 C for 30

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02149.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.Ganymedes oaklandin. sp. (Ganymedidae) from the intestine ofGammarus fasciatus(Say) is described, and its life cycle is given. In the trophic stage the gregarine is acephaline, with an elongated cylindrical body slightly tapered anteriorly, and is up to 298 × 64 μ. The gametocysts are up to 121 × 99 μ, and are covered with a secreted thick sticky gelatinous coat. The spores are released from the gametocyst by rupturing of the cyst wall. The spore body is spherical, approximately 6 μ in diameter, and has 4 episporal rays about 20 μ

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02150.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.Fine structure ofPentatrichomonas hominisis described in the light of previous light microscopic findings. The relationships among kinetosomes #1‐#4 and R are like those previously reported orhomonas gallinae, and the same is true of the rootlet filaments associated with the several kinetosomes. The kinetosome (I) of the independent flagellum is situated just behind the reflection of the sigmoid filaments of kinetosome #2 onto the pelta and parallels these filaments for a considerable distance. The peltaraxostylar junction consists of 3 layers: the capitulum of the axostyle (outer, the pelta (intermediate, and the sigmoid rootlets of kineto some #2 (inner). The pelta overlaps the axostylar capitulum to a variable extent. The parabasal body consists of elongate and flattened cisternae of smooth endoplasmic reticulum surrounded by numerous small vesicles. There are 2 typically cross‐striated parabasal filaments, filament 2 probably contributing most, if not all, the material to the slender, periodic organelle that underlies the parabasal body and usually does not extend far beyond the posterior end of the nucleus. The periodic costa is paralleled by paracostal granules, but there are few, if any, paraxostylar granules. The ultrastructure of the costa appears to be a network of flattened hexagons, with a single fibril projecting thru each of the hexagonal areas. The major cross‐striations are made up largely of densely‐stained filaments which are occasionally cut in cross section. The undulating membrane consists of a cytoplasmic fold extending from the dorsal surface of the organism and of the attached part of the recurrent flagellum, which is closely applied to the fold. The segment of the membrane dorsal to the flagellum, presumably the “accessory filament,” contains the marginal lamella, a membrane folded upon itself and with periodicity virtually indistinguishable from that of the rootlet filament of ki

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02151.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.The sporulated oocysts ofEimeria utahensissp. n. from 2 species of kangaroo rats in northwestern Utah are described. The oocysts averaged 42.0 by 39.3 μ, and had rough, yellow‐brown walls, about 3 μ thick. In each sporocyst, a substiedal body was seen beneath the Stieda body; this is the 1st report of such a structure in anyEimeriaspecies.E. utahensiswas found in 3.6% of 196Dipodomys ordiiand 19.4% of 36 D.microps. The incidence was higher in young adult than in adult Ord kangaroo rats and lowest in juveniles; inD. micropsonly adults were infected. The mean prepatent period was 9.8 days. The patent period could not be determined because of apparent reinfections; there was no evidence of immun

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02152.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.Plasmodium pinottiiis an avian malaria parasite originally isolated from the Brazilian toucan, and maintained chiefly in the pigeon, in which it is extremely pathogenic. Infections must be transferred by blood inoculation, since gametocytes are no longer produced (and, in any event, the vector is unknown). Unlike most forms of avian malaria, pinottii malaria in the pigeon is characterized by fever, often high, with peaks at the time of parasite reproduction. Blood sugar levels vary considerably even in healthy birds, in which the mean was found to be 267 ± 9.2 SEm mg per 100 ml plasma (range 208–335, based on examination of 14 individuals. Values during fasting approximated those when feeding wasad libitum. Levels tended to rise in the early stages of the infection, reaching a mean of 305 ± 14.5 mg per 100 ml plasma (based on 10 cases) while parasitemia was 20‐49%. At death the mean (determined from 46 birds) had dropped to 155.8 ± 15.5 mg per 100 ml. However there is little reason to think that parasite demand on the host's glycogen reserves was a significant factor in causing death, despite the very high parasitemias often r

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02153.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.The life cycle ofVolvox carteriwas studied in axenic culture using the NB‐3 and the NB‐7 strains isolated from Nebraska. Vegetative colonies of both strains contain 8–12 asexual reproductive cells (gonidia) which divide to form daughter colonies. During daughter colony formation, the reproductive cells of the daughters are delimited at an early stage of cleavage. Gonidia are delimited at the division from 16 to 32 cells, but eggs and male initial cells are not differentiated until the division of the 32‐celled stage. In all instances the reproductive cells are the products of unequal cleavages.Male and female colonies are formed in separate clones. Female colonies contain approximately 20 eggs. Male colonies have approximately 50 male initial cells, each of which forms a sperm bundle containing 64 or 128 sperm. Sperm bundles penetrate female colonies and fertilize the eggs. Zygote formation, zygote germination, and the development of gone colonies is described. Sexual type was inherited in a 1:1 ratio.Male colonies appear spontaneously in the male strain, but female colonies were formed in the female strain only in the presence of a substance produced by colonies from male cultures. This female inducing substance is produced in male cultures primarily, if not exclusively, by male colonies rather than by vegetative colonies. The female inducing substance is heat labile and non‐dialyzable. Activity is destroyed by Pronase, but not by trypsin, chymotrypsin or ribonuclease.Gonidia appear to be most susceptible to female induction during the early stages of their expansion prior to

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02154.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.A continuous culture device suitable for controlled growth ofEuglna gracilisis described. It could probably be adapted to other similar cell types with generation times no greater than 150–200 hr

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02155.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY

摘要:

SYNOPSIS.In the anemia which accompanies infection byLeucocytozoon simondiin Pekin ducks there was a far greater loss of erythrocytes than could be accounted for as a result of direct physical rupture by the parasite. Erythrocyte loss began at the same time the 1st parasites appeared in the blood and was severest just prior to maximum parasitemia. Blood replacement and parasite loss occurred simultaneously. Examination of the spleen and bone marrow revealed that erythrophagocytosis was not the cause of anemia as reported for infections ofPlasmodium, BabesiaandAnaplasma. An anti‐erythrocyte (A‐E) factor was found in the serum of acutely infected ducks which agglutinated and hemolyzed normal untreated duck erythrocytes as well as infected cells. This A‐E factor appeared when the 1st red cell loss was detected and reached its maximum titer just prior to the greatest red cell loss. Titers of the A‐E factor were determined using normal uninfected erythrocytes at temperatures between 4 and 42 C. Cells agglutinated below 25 C and hemolyzed at 37 and 42 C. These results indicated that the A‐E factor could be responsible for loss of cells other than those which were infected and could thus produce an excess loss of red cells.Attempts to implicate the A‐E factor as an autoantibody were all negative. The A‐E factor was present in the gamma fraction of acute serum but no anamnestic response could be detected when recovered ducks were reinfected. Anemia was never as severe in reinfections as in primary infections. The A‐E factor also never reached as high a titer and was removed from the circulation very rapidly in reinfected ducks.It is concluded that red cell loss in ducks with acuteLeucocytozoondisease results from intravascular hemolysis rather than erythrophagocytosis. The A‐E factor responsible for hemolysis is more likely a parasite product rather

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1968.tb02156.x

出版商:Blackwell Publishing Ltd    

年代:1968

数据来源: WILEY