bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative Studies of Effect of Temperature on Three Species of Entamoeba*
Authors: SIDDIQUI WASIM A. 
Published: May 2007

SYNOPSIS. Three morphologically indistinguishable species, Entamoeba histolytica, E. invadens and E. moshkovskii, were compared with regard to the effect of temperature. Temperature tolerance studies showed that the thermal endpoints (100% death) of DKB and the Laredo strains of E. histolytica, DSR strain of E. moshkovskii and IP strain of E. invadens were in the descending orders of 43°, 41°, 41° and 39°C respectively. DKB strain seemed to be very sensitive to temperatures below 30°C. The Laredo strain of E. histolytica and DSR strain of E. moshkovskii were similar in their range of temperature tolerance.The DKB strain of E. histolytica has been adapted to grow at 30°C and IP strain of E. invadens at 35°C, with Clostridium perfringens as the associate in both cases. Comparison of normal and temperature‐adapted strains of the three species of Entamoeba with respect to population cycle showed that at higher temperatures the multiplication rate is higher and the population reaches its peak in 2 to 3 days, whereas at the lower temperature the multiplication rate tends to decrease and the maximum population is reached by the 4th day. Individual trophozoites from the 30°C‐adapted strain of E. histolytica were larger than those of the parent strain grown at 37°. Amoebae of the IP strain of E. invadens adapted to 35° were smaller than those of the original strain grown at 30°.The observations indicate that the Laredo strain of E. histolytica, isolated from a patient with amoebic dysentery, is an unusual mutant of a typical strain of E. histolytica, which on one hand shows affinity with typical E. histolytica and on the other hand with E. moshkovskii and E. invadens.
Physiological Properties of Tetrahymena vorax†
Authors: SHAW ROSS F. , WILLIAMS NORMAN E. 
Published: May 2007

SYNOPSIS. Four strains of ciliates regarded as strains of Tetrahymena vorax were studied nutritionally and serologically. All grew on a chemically defined medium and phospholipid was generally stimulatory. It is concluded from the results of the present study, together with information available in the literature, that two of the strains (V1 and PP) are actually strains of T. pyriformis. This leaves T. vorax represented by two extant strains, V2 and Tur, both of which are polymorphic.Evidence is presented for “stable transformations” in two of the strains included in the study, i.e., stocks have spontaneously developed phenotypic differences which are uniparentally inherited. The potential importance of studies of uniparental inheritance for physiological and developmental genetics is discussed.
Accumulation of Extracellular Amino Acids by Euglena gracilis
Authors: McCALLA D. R. 
Published: May 2007

SYNOPSIS. Normal Euglena gracilis, strain z, growing in the light in defined medium (initial nitrogen concentration 140 μ/ml) depletes the medium of all ninhydrin‐positive N by the time a cell density of 2 million per ml is reached. A further 2‐ to 3‐fold increase in the cell number takes place in the absence of exogenous N. The N content of an early log phase cell is about 100 picograms but decreases very rapidly as the culture continues to grow, reaching 22 picograms in the stationary phase. When grown in the dark, normal cells take up N somewhat more slowly but the supernatant fluid from saturation cultures is again devoid of N.At modest cell densities, the permanently bleached strains examined contain less N per cell than do normal strains. The cultures of the bleached strains achieve a maximum density of about 1 to 2 million per ml rather than the 4 to 5 million reached by the normal strain. As a result, supernates from stationary phase cultures of bleached cells still contain a large proportion of the total N supplied.Paper chromatographic analysis of these supernates reveals several ninhydrin‐positive compounds. Most of these have been identified as common amino acids. Some of the properties of two unidentified, ninhydrin‐positive compounds are described.
Cultivation of Rumen Protozoa. I. Factors Influencing the Cultivation of Rumen Oligotrich Protozoa “In Vitro”
Authors: Rahman S. A , Purser D. B. , Tyznik W. J. 
Published: May 2007

SYNOPSIS. Factors influencing the cultivation of entodinia in vitro have been studied. It was found that removal of particulate material, culture division, or a combination of both resulted in similar maximum protozoal concentrations. At the same time, untreated culture concentrations declined rapidly after reaching a maximum concentration at about the tenth day.At concentrations of streptomycin greater than 25 μg per ml of media, increasing the level of streptomycin extended the time required for a culture to attain a maximum protozoal concentration. A significant relationship (P>.01) was demonstrated between the starch concentration and the protozoal concentration, and it was found that various combinations of starch and streptomycin produced different relative protozoal concentrations in initial and established cultures. Implications arising from these results are discussed.
Localization of Ciliary Primordia in Induced Abnormal Cysts of Oxytricha. fallax
Authors: Hashimoto Kaneji 
Published: May 2007

SYNOPSIS. Precystic organisms embedded in agar become abnormal cysts. Some of them are excystable rod‐like or ellipsoid forms and the others, non‐excystable fiat ones. Major axis of the rod‐like or ellipsoid cysts is parallel with the body axis of the previous precystic organisms, because when the cysts are formed the protoplast within the secreted cyst walls rotates or agitates slightly around the major axis but movement around the minor axis is precluded.The fibrillar structures appearing in excystment from abnormal cysts are bilaterally symmetrical, different from the normal spherical cysts showing radial symmetry. The two poles from which the fibrils radiate are situated opposite each other but not at the extremities of the cyst. The locus of the anterior pole corresponds to the site of oral primordia in dividers and reorganizers.When the anterior part of the original adoral membranelles (AZM) in the early precystic animals is removed, the ellipsoid cysts from the abbreviated animals show a disturbance of the anterior fibrillar arrangement. The primoidium of the future AZM runs straight from the anterior extremity of the cyst toward the uninjured posterior pole. Ellipsoid cysts from precystic animals after the posterior region is removed similarly have disturbed fibrils near the posterior extremity of the cyst. The AZM primordium then arising on excystment extends from the uninjured anterior pole toward the damaged posterior extremity of the cyst. Similar events are found also in spherical cysts from anterior and posterior fragments of precystic animals.In either case, though the initial phase of the AZM primordium shows irregular contour, leaf‐like shape is accomplished later accompanying the increase of primordial granules, while the other ciliary primordia such as undulating membrane and cirri arise at their corresponding areas. All can produce normal excysted animals.The ciliary primordia appearing upon excystment, notably that of the AZM, therefore seem to have descended from the precystic stage or foregoing trophic one.
Cytological and Cytogenetical Studies on Paramecium polycaryum. V. Lethal Interactions in Certain Stocks*
Authors: Takayanagi Tan , Hayashi Shinji 
Published: May 2007

SYNOPSIS. Evidence is presented for killer and sensitive animals in Paramecium polycaryum. The killer animals excreted in the culture medium a lethal substance which killed the sensitive animals. The lethal substance was unstable at high temperatures and was completely precipitated by centrifugation at 10,000 rpm for 30 minutes. Comparative immunity to killing by killer animals was shown to be possessed by some animals of certain sensitive stocks.Attempts to find a cytoplasmic particle comparable to “kappa” in P. aurelia in killer animals were not successful.
A Comparative Study of Hartmannellid Amoebae
Authors: ADAM KATHERINE M. G. 
Published: May 2007

SYNOPSIS. Twenty strains of hartmannellid amoebae have been studied. All the strains grew axenically in liquid and chemically defined media. Strains were found to differ their rate of growth, optimum temperature for growth and in amino acid requirements. All except one strain (Lilly) were found to be serologically related by the immobilization test. Direct observation of the trophozoites and cysts, and the results of serological and physiological tests, have led to the conclusion that the 20 strains should comprise a single species until further information is gained on these and other representatives of the genus.Earlier literature on the classification of hartmannellid amoebae has been critically reviewed, and it is concluded that Hartmannella castellanii Douglas 1930 is the correct name for the species. It is suggested that Acanthamoeba castellanii (Volkonsky 1931), Hartmannella glebae (Dobell 1914) and H. rhysodes Singh 1952 became synonyms of H. castellanii, and that Mayorella palestinensis Reich 1933 be transferred to the genus Hartmannella.Some strains of H. castellanii were able to grow at mammalian body temperature. Since the species appears to be common and widely distributed, and farms cysts which resist desiccation, it is probable that the occurrence of amoebae in mammalian cell cultures has arisen by contamination from the air.
The Somatic and Oral Infraciliature of the Enigmatic Giliate Cyathodinium piriforme*
Authors: PAULIN JEROME J. , CORLISS JOHN O. 
Published: May 2007

SYNOPSIS. The unusual patterns of infraciliary kinetosomes on the body and in the large anterior depression of the trophont stage of this difficult‐to‐classify ciliate have been examined by use of the Chatton‐Lwoff silver impregnation technique. In our material there are nine rows of somatic cilia, arranged more or less concentrically around the oral cavity at the anterior end of the pyriform‐shaped body; in the cavity itself there are eight quite separate rows of “vestibular” ciliature. Erratically distributed on posterior areas of the body are argentophilic “granules” which may be non‐cilia‐bearing kinetosomes. A contractile vacuole pore, described for the first time, is located on the ventral surface in the posterior third of the body to the right of the midline.Still more information is needed to be able to establish the most appropriate taxonomic allocation for Cyathodinium. It is suggested that a combination of fine structural (electron microscopical) and morphogenetic (fission, stomatogenesis, reorganization) studies is required to elucidate both the form and the function of the several unique features of Cyathodinium and that a new understanding of these will permit resolution of the problem of the systematic status of the ciliate.
The Behavior and Pathogenicity of Two Strains of Trichomonas gallinae in Cell Cultures*
Authors: HONIGBERG B. M. , BECKER R. DiM. , LIVINGSTON M. C. , MCLURE M. T. 
Published: May 2007

SYNOPSIS. A comparison of the effects upon trypsin‐dispersed chick liver cell cultures of a virulent (Jones' Barn) and a non‐pathogenic (Lahore) strain of Trichomonas gallinae revealed significant differences in behavior of the parasites in cell cultures and in the response of such cultures. The virulent strain multiplies faster in nutrient medium in the presence of cell cultures; stimulates great activity of the macrophages; is not handled effectively by these phagocytes in which it can multiply causing their ultimate destruction; is found significantly more often within the cytoplasm of the liver epithelial and fibroblast‐like cells; causes very much more profound degenerative changes in all the cells, both invaded and non‐invaded; and suppresses effectively the division rate of the fibroblast‐like cells. On the other hand, the nonpathogenic strain multiplies at a lower rate in the presence of cell cultures; stimulates less activity of the macrophages; is handled readily by these phagocytes in which it multiplies only very rarely, if ever; is found seldom within the liver epithelial and fibroblast‐like cells; causes far less degeneration of all the cell culture elements; and suppresses significantly less the dlvision rate of the fibroblast‐like cells.At the end of a 20–24 hour period typically only a few living cells are left in cultures exposed even to attenuated isolates of the virulent strain, whereas those inoculated with the mild one do not show much degeneration even after 28 hours. The effects upon the cell cultures of cell‐free filtrates of actively growing trichomonad cultures are relatively minor, but the changes caused by the filtrates of cultures of Jones' Barn strain appear to be more extensive than those caused by similar filtrates of Lahore strain.
The Lesser Haemosporidina*
Authors: MANWELL REGINALD D. 
Published: May 2007

SYNOPSIS. Although the Haemosporidina are a large group, few of them arc well known. Those considered here are called the “lesser Haemosporidina” because they have, on the whole, much less impovtance than the malaria parasites of man. They are, nevertheleq far from insignificant because some cause serious disease in the lower animals and probably play an important role in the maintenance of biological balances. Their use as research tools has also often led to very useful discoveries directly applicable to human malaria.Only four species of the 60 or so now known in the genus plasmodium parasitize man; we are still ignorant of many of the most elemental facts relating to the biology of the rest. The rectors of many remain undiscovered and, partly as a result, their exoerythrocytic stages have never been observed. Even when such knowledge cxists. there are many lacunae in what we know of thcir physioloey. A really practical method of cultivating the various stapes would be of great help.We also need much more knowledge of the close relatives of the malaria parasites, comprising the genera Hueinoprofeits, Hepatocystis, and Lertcocytoroon. There are close parallels in their host occurrence which undoubtedly have evolutionary significance. Yet such facts are difficult to interpret, although it seems likely that Haenzoproteus may be the oldest of the four.Whether Babesia and Dactylosoma should be included in the Harniosporidimz has been questioned. It is the author's opinion that it would be better to retain them. Despite important differences there are basic similarities. Much remains unknown about Babesia and very little of importance is known about Dactylosoma. This genus is known from Anura all over the world, and seems usually to occur in frogs and toads, in which the species is usually thought to be D. Ranarum. Other species have been occasionally reported from other amphibia and even from fish. Nothing at all is known of its transmission or life cycle. Its occurrence in frogs in very widely separated areas may have the same significance which Metcalf many years ago attached to the similar occurrence of the opalinids: it may be evidence for the existence in remote times of land bridges connecting land masses now remote from one another.
Effect of Nitrofurans on the Chloroplast System of Euglena gracilis
Authors: McCALLA D. R. 
Published: May 2007

SYNOPSIS. Twelve derivatives of 5‐nitrofuran were tested on Euglena grarzlis. All rendered the organism permanently apoplastidic and, at somewhat higher concentrations, killed. The furan analogues of 3 of these compounds had no effect on the chloroplast system and were less toxic than the nitrcfurans. Low concentrations of nitrofurantoin and nitroiuraldehyde inhibited formation of chlorophyll when etiolated cells irere illuminated.Exposure of euglena to low concentrations of these agents for about 2 generation times. followed by plating on drug‐free mediurn. resulted in a high proportion of bleached colonies. It is theretore concluded that the nitrofurans induce apotplastidy by causing permanent damage to the chloroplast system rather than by inhibiting its replication temporarily. Since one of the nitrofurans which was found to bleach euglena, NFT–3‐amino‐6[‐2‐(5‐nitro‐2‐furyl) vinyl]‐1,2,4‐triazine–is known to cause specific inhibition of DNA synthesis in bacteria, nitrofurans may perhaps bleach euglena through selective damage to chloroplast‐DNA or to the DNA‐synthesizing system of the chloroplast.
Permeability to Sugars and Fatty Acids in Polytoma obtusum
Authors: CHAPMAN LINDA F. , CIRILLO VINCENT P. , JAHN THEODORE L. 
Published: May 2007

SYNOPSIS. Whole cells of Polytoma obtusum do not utilize glucose or other hexoses, but cell‐free extracts show glucokinase activity having a pH optimum at 8.5 and a Q10 of 2.4 between 0–20°C. Lack of glucom utilization by whole cells reflects a permeability barrier to all sugars.To determine whether inability of acetate‐grown cells to utilize butyrate also denoted a permeability barrier, permeability to acetate and butyrate was studied in acetate‐ and butyrate‐grown cells However, acetate‐grown cells accumulated C‐14 labeled butyrate against a concentration gradient. Therefore inability of acetate‐grown cells to utilize butyrate does not denote a permeability barrier.Acetate‐kinase activity was consktently demonstrated in cell‐free extracts of both acetate‐ and butyrate‐grown cells. Butyrate kinase was consistently found only in butyrate‐grown cells. However, the absence of buttymte kinase in acetate‐grown cells cannot be claimed since occasionally butyrate kinase activity was demonstrated in extracts of acetate‐grown cells.
Physiological Studies on the Rumen Ciliate, Ophryoscolex purkynei Stein
Authors: MAH ROBERT A. , HUNGATE ROBERT E. 
Published: May 2007

SYNOPSIS. Fermentation of wheat by a clonal population of Ophryoscolex purkynei obtained from an in vitro culture yielded butyrate, acetate, smaller amounts of propionate, and traces of formate and lactate. H2 and COz were formed in a ratio of approximately 2:1. The soluble sugars tested were not fermented in manometric experiments. Decomposition of pectin by O. Purkynei is due to pectin esterase and transeliminase; the latter enzyme resembles the bacterial transeliminase rather than the fungal pectin transeliminase. The occurrence of these enzymes seems odd since the end products do not appear to be metabolized.The rate of fermentation of wheat by washed suspensions of protozoa agreed with the rate determined by following gas production in a normal culture during a 24‐hr period. The rate was lower than that reported for the holotrichous rumen ciliates; the total products formed per cell per hour by the washed suspension were 0.295 mpM.The formation of gas by fermentation of soybean and linseed oil meals was due to the starch and not protein in these materials. Manometric experiments with the pure proteins, casein, gliadin, and glutenin showed no gas evolution. Ammonification of these substrates in addition to plant chloroplasts was determined. Linseed oil meal gave a high value of 0.02 mμM/cell/hr which is of practical magnitude when compared to the rate of formation of acid, 0.08 mμM/cell/hr.Based on a concentration of 4000 protozoa/ml, estimation of the proteolytic activities of O. Purkynei indicated that it can account for 1.5% of the total ammonification. But, it can account for nearly 11% per day of the nitrogen supplied to the host when the protozoa are passed on to the abomasum. Its contribution to the volatile acids produced in the rumen is 3%, assuming the maximum rate of acid formation from wheat. Ophryoscolex can be of significance in the rumen if it occurs at high concentrations (4W/ml) but the rate of fermentatiodcell is too low to assign much importance to this organism when it occurs in low numbers.
An Electron Microscopic Study of the Final and Initial Forms of Plasmodium gallinaceum in Thin Sections of Infected Tissue Cultures*
Authors: MEYER H. , de OLIVEIRA MUSACCHIO M. 
Published: May 2007

SYNOPSIS. Merozoites from Plasmodiunz gallinaceum (exoerythrocytic forms) have been observed with the electron microscope in thin sections of infected tissue cultures. When still in segmenter formation, at the end of the intracellular cycle, a small canaliculum can be observed in their proximal part which runs from the nuclear region down into the cytoplasmic core of the segmenter, where, in some sections, it continues directly into the endoplasmic reticulum of the core.Large, vacuole‐like empty spaces in the merozoites recall swollen mitochondria. They show short villi at the periphery, instead of the typical cristae; they resemble the mitochondria of starved tissue cells.In the distal pole of the merozoites, one or two oval bodies of great electron density are present, among several smaller granules, both structures still being of unknown significance. The rest of the cytoplasm is of great electron density and shows a fine granulation.In the young trophozoites the oval bodies and the smaller granules disappear. Also, mitochondria are not found just after parasites enter a cell. These, however, reappear soon.The contact of the trophozoites with the cytoplasm of the host is intimate. Both surface membranes of the parasite are visible, mostly intact, but showing also openings which are considered artifacts, since no images have been obtained which indicate a passage of material through them from the host to the parasite. It is believed, however, that the parasite takes up material from the host through the membranes by an osmotic process. The fading of the electron density and the greater distance between the particles of its cytoplasm in the growing parasite seem to prove this. The particles which are responsible for the electron density of the merozoites, and of the young trophozoites, do not differ in their aspect from the RNA particles of the host cells.The nucleus, which in the merozoites and in the very first intracellular stages shows a homogenous fine and dense granulation, develops a darker region later, of irregular shape, which is located eccentrically, and is considered the nucleolus of these forms.
Study of the Cellular Action of Drugs with Protozoa. II. Comparative Study of the Inhibitions Induced by Hypocholesteremic Agents on Ochromonas danica Multiplication; Annulment by Oleic Acid*
Authors: AARONSON S. , BENSKY BARBARA 
Published: May 2007

SYNOPSIS. Several hypocholesteremic agents inhibit multiplication of Ochromonas danica, Euglena grucilis, and Tetrahy‐menu pyriformis. Inhibiting O. danica are benzmalecene, triparanol, diazacholestanol. 3‐β‐(2‐diethylaminoethoxy) androst‐5‐en‐17‐one, α‐phenylbutyric acid, β‐diethylaminoethyldiphenyl‐n‐propylacetate (SKF‐525A) 2,2‐diphenyl‐1‐ (β‐dimethylaminoethoxy)pentane (SKF‐3301A), trans‐3‐(p‐chlorophenyl)‐2‐[p‐(2‐diethylaminoethoxy)phenyll‐2‐pentenenitrile (P‐3429), frans‐3‐[p‐(2‐diethylaminoethoxy) phenyll‐2‐pentenenitrile (P‐3013), vanadyl SO† and L‐thyroxine but not nicotinic acid, 3‐pyridylacetic acid, 3‐pyridylacetamide, nicotinuric acid, p‐aminosalicylic acid. tris‐(2‐dimethylaminoethyl) phosphate (SKF‐7732‐A3), tris‐ (2‐diethylaminoethyl) phosphate (SKF‐7997‐A3), 2,3‐bis[p‐(2‐diethylaminoethoxy) phenyl] acrylonitrile bis (P‐2681).Inhibition of Ochromonas multiplication by benzmalecene, triparanol, diazacholestanol, SKF‐525A. SKF‐3301A, P‐3013, and P‐3429 was annulled by lecithin, TEM, and specifiically by oleic acid. The following compounds equimolar with oleic acid were ineffective: stearic, palmitic, myristic, and lauric acids; cholesterol, stigmasterol, ergosterol, lanosterol, and β‐sitosterol; mevalonic acid lactone, geranyl acetate, farnesol, and squalene.Evidence is presented for the usefulness of protozoa as detectors of toxicity and possible harmful side effects of inhibitors of lipid metabolism in mammals.