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Applying the socio-ecological model to understand factors associated with sugar-sweetened beverage behaviours among rural Appalachian adolescents
- Brittany A McCormick, Kathleen J Porter, Wen You, Maryam Yuhas, Annie L Reid, Esther J Thatcher, Jamie M Zoellner
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- Journal:
- Public Health Nutrition / Volume 24 / Issue 11 / August 2021
- Published online by Cambridge University Press:
- 11 January 2021, pp. 3242-3252
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Objective:
The objective of the current study was to identify factors across the socio-ecological model (SEM) associated with adolescents’ sugar-sweetened beverage (SSB) intake.
Design:This cross-sectional study surveyed adolescents using previously validated instruments. Analyses included descriptive statistics, ANOVA tests and stepwise nonlinear regression models (i.e., two-part models) adjusted to be cluster robust. Guided by SEM, a four-step model was used to identify factors associated with adolescent SSB intake – step 1: demographics (i.e., age, gender), step 2: intrapersonal (i.e., theory of planned behaviour (attitudes, subjective norms, perceived behavioural control, behavioural intentions), health literacy, media literacy, public health literacy), step 3: interpersonal (i.e., caregiver’s SSB behaviours, caregiver’s SSB rules) and step 4: environmental (i.e., home SSB availability) level variables.
Setting:Eight middle schools across four rural southwest Virginia counties in Appalachia.
Participants:Seven hundred ninety seventh grade students (55·4 % female, 44·6 % males, mean age 12 (sd 0·5) years).
Results:Mean SSB intake was 36·3 (sd 42·5) fluid ounces or 433·4 (sd 493·6) calories per day. In the final step of the regression model, seven variables significantly explained adolescent’s SSB consumption: behavioural intention (P < 0·05), affective attitude (P < 0·05), perceived behavioural control (P < 0·05), health literacy (P < 0·001), caregiver behaviours (P < 0·05), caregiver rules (P < 0·05) and home availability (P < 0·001).
Conclusions:SSB intake among adolescents in rural Appalachia was nearly three times above national mean. Home environment was the strongest predictor of adolescent SSB intake, followed by caregiver rules, caregiver behaviours and health literacy. Future interventions targeting these factors may provide the greatest opportunity to improve adolescent SSB intake.
The Morphology and Biology of Herpetomonas patellae, n.sp., parasitic in the Limpet, Patella vulgata, together with Remarks on the Pathogenic Significance of Certain Flagellates found in Invertebrates
- Annie Porter
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- Journal:
- Parasitology / Volume 7 / Issue 3 / October 1914
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- 06 April 2009, pp. 322-329
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Many herpetomonads have been recorded from various insects belonging chiefly to the Diptera and Hemiptera, but until the present instance, members of this genus of flagellates have not been found in the Mollusca and very few in other Invertebrata. Also the habitat of the herpetomonads has usually been either the main alimentary tract or the haemocoel of their hosts. Digestive glands hitherto have not been recorded as being infected.
Some microsporidia found in certain fishes and insects in eastern Canada
- H. B. Fantham, Annie Porter, L. R. Richardson
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- Journal:
- Parasitology / Volume 33 / Issue 2 / May 1941
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- 06 April 2009, pp. 186-208
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An account is given of some Microsporidia found in certain fishes and insects in eastern Canada, among which are new species of Nosema, Perezia and Gurleya.
Nosema pimephales n.sp. produces large cysts or tumours in the abdomen of Pimephales promelas, one out of a large number from Lake Guindon, Province of Quebec, being infected.
Nosema branchiale Nemeczek has been observed from a cod, Gadus callarias. The organism is shown to be a Nosema, though the incomplete original description has caused doubts as to whether some other genus was involved. Further details are now given.
Nosema apis Zander and N. bombi Fantham & Porter have been found in Canada in hive-bees and humble-bees respectively, the latter being recorded from a new host, Bombus vagans.
Glugea hertwigi n.var. canadensis is described from Osmerus mordax from Lake Edward.
Perezia aeschnae n.sp. has been found in nymphs of the large dragonfly, Aeschna grandis, collected near Montreal and is described and illustrated.
Perezia legeri Paillot has been observed in larvae of Pieris brassicae.
These appear to be the first records of Perezia from insects in North America, and the zoogeographical distribution of the genus is extended to the Odonata.
Gurleya aeschnae n.sp, is described from a nymph of Aeschna grandis. It is the first species of Gurleya to be described from the Odonata and the first record of the genus from the North American continent.
Thelohania corethrae Schuberg & Rodriguez is described from the larvae of Chaoborus flavicans. Measurements of the parasite, which were lacking in the original description, are now supplied.
Thelohania bracteata from larvae of Simulium bracteatum and larvae and one adult S. venustum and Thelohania fibrata from larvae of Simulium venustum are recorded from places in the Province of Quebec. The need of reinvestigation of the species of Thelohania from various Simulium and the possibility of there being but one species, Thelohania varians Debaisieux, are indicated.
Thelohania legeri Hesse is recorded as a parasite of larvae of Anopheles punctipennis in Quebec Province and of A. gambiae in Zululand. It is probably the most widely distributed species of Thelohania, occurring in Anophelines in Europe, Asia, Africa and North America.
Some general remarks regarding zoogeographical distribution, habitat, host-specificity and possible origin of species and varieties in connexion with Gurleya, Perezia and Thelohania are presented.
The structure and life history of Crithidia pulicis, n. sp., parasitic in the alimentary tract of the human flea, pulex irritans
- Annie Porter
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- Parasitology / Volume 4 / Issue 3 / October 1911
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- 06 April 2009, pp. 237-254
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1. Crithidia pulicis, n. sp., is a parasite of the alimentary tract of the human flea, Pulex irritans.
2. The fleas used in this investigation were bred to the third generation in special “flea cages” on the human body. “Wild” fleas were examined and yielded the same parasite. Both larvae and adult fleas were examined.
3. C. pulicis exhibits pre-flagellate, flagellate and post-flagellate stages in its life history and these phases gradually develop, the one from the other.
4. The flagellate form is very active, movement being accomplished by means of the myonemes of the membrane and body.
5. Pre-flagellates (figs. 1−8) are oval bodies, from 2·3 μ to 7 μ long by 1·5 μ to 4·5 μ broad. The nucleus contains much chromatin and a small karyosome may be present. The blepharoplast is large. The flagellum develops from a chromatophile area. The rate of acquisition of flagellum and membrane varies in individual parasites. Division rosettes are frequent. The pre-flagellates have a somewhat frail appearance.
6. The flagellates of C. pulicis (figs. 9−17) are 26 μ to 65 μ long. Their cytoplasm is richly but finely granular, the nucleus well marked, the blepharoplast large, showing slight variations in shape. Chromidia may be present. The undulating membrane is large, well marked and possesses myonemes which can be detected in the living organism. The free flagellum is relatively short.
7. Post-flagellates (figs. 23−36) are from 3 μ to 6 μ. by 2·0 μ to 4·6 μ. They occur in the rectum and dejecta of the fleas. They are produced by concentration of the protoplasm round the nucleus and blepharoplast with absorption of the membrane and flagellum and finally the production of a thin varnish-like coat.
8. Longitudinal division (figs. 15−22) is the method of multiplication. It occurs in the pre-flagellate and flagellate stages. It may be symmetrical or asymmetric. Division is initiated by that of the blepharoplast, followed by that of the flagellum, membrane and nucleus and finally the body cytoplasm. Two types of asymmetric division have been observed.
9. The method of infection is contaminative, the post-flagellates in the faeces being the source of infection. There is no evidence of hereditary infection.
10. Crithidia pulicis is a member of the genus Crithidia, and is a true parasite of the insect, Pulex irritans.
The occurrence of Pneumocystis carinii in mice in England
- Annie Porter
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- Parasitology / Volume 8 / Issue 3 / January 1916
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- 06 April 2009, pp. 255-259
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A fertile source of error in protozoology is to be found in the overlooking of the occurrence of mixed infections in a host. Two organisms, each independent of the other, may happen to coexist in the intestine of an insect or the blood of a vertebrate, the result being that the investigator may confuse stages in the life-cycles of parasites which are not related to each other. This source of error has led to unwarranted generalisations which have impeded scientific progress for years. Two examples at once come to mind—the trouble wrought by Schaudinn in 1904 in confusing the life-cycles of the protozoa found in the little owl, and the impediment put in the way of progress by the omission of certain workers to recognise that Crithidia grayi was not a part of the life-cycle of a trypanosome. The existence of mixed infections was overlooked in each case.
Further remarks on the genera Crithidia, Herpetomonas and Trypanosoma, and Dr Woodcock's views thereon
- Annie Porter
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- Parasitology / Volume 4 / Issue 2 / June 1911
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- 06 April 2009, pp. 154-163
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Through the courtesy of the Editors of Parasitology I have been favoured with an advance proof of the remarks of Dr Woodcock on a former note of mine relating to the procedure of the Recorder of the Protozoa section of the International Catalogue of Scientific Literature and the Zoological Record. In my article I raised three points. (1) In certain cases where the generic names Crithidia and Herpetomonas were placed in inverted commas in the Catalogue, I stated that no direct evidence existed to justify such a procedure. (2) I protested against such meddlesomeness on the part of the Recorder. (3) I stated that the Recorder, who had not worked on the parasites themselves, held, consequently, extreme views. Dr Woodcock's so-called reply has afforded me considerable amusement and it is a matter of surprise to me that he has been so ill-advised as to write such a poor rejoinder—he must know that he has made no answer to my remarks. That the weakness of his position is well known to him is shown by his recourse to the tactics of vituperation and innuendo, where he remarks that my method of criticism is “not straightforward but, on the contrary, distinctly oblique.” Dr Woodcock has no case and so has adopted metaphorically the old, old method of “abusing the plaintiffs attorney,” in the shape of discussing my own papers on parasites not originally under discussion. I am sorry that one who apparently claims to be an authority is reduced to such second-rate methods. While I regret the necessarily severe character of this, my rejoinder, it is impossible to deal otherwise with the numerous side issues raised by Dr Woodcock.
The Life-Cycle of Herpetomonas jaculum (Léger), Parasitic in the Alimentary Tract of Nepa cinerea
- Annie Porter
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- Parasitology / Volume 2 / Issue 4 / December 1909
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- 06 April 2009, pp. 367-391
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(1) Herpetomonas jaculum is a parasite of Nepa cinerea, occurring in the alimentary tract of its host.
(2) The life-history of the parasite may be conveniently divided into three stages, the pre-flagellate, flagellate and post-flagellate stages, which gradually merge into one another.
(3) The movements of the parasite are less flexible than those of Crithidia, as Herpetomonads have no undulating membrane. The flagellum is the most active agent in effecting motion.
(4) The pre-flagellate stages of the parasite (Pl V, Figs. 1–18) are best observed in the crops of nymphs of Nepa cinerea. The parasites at first are oval (Figs. 1–6). They vary in size from about 4μ to 5μ long and from 2μ to 2·5μ broad. They show nucleus and blepharoplast, and may divide longitudinally before flagella are acquired (Figs. 2–4). The flagellum of each parasite arises from a region near to the blepharoplast but not directly from it (Figs. 5–9).
(5) The flagellate stage of the organism (Pl. V, Figs. 19–36) is that best known. H. jaculum is from 13μ to 33μ long and from 1μ to 4μ broad, the size varying according to the recency or otherwise of longitudinal division. Myonemes (Figs. 20, 21, 38) are present on the body. The flagellum is at least as long again as the body. The nucleus contains a number of grains of chromatin (Figs. 28, 34), sometimes in the form of eight large grains (Figs. 34, 36), sometimes as very fine granules (Figs. 22, 31). The blepharoplast is in the anterior, pre-nuclear, region of the parasite, and is usually rod-like (Figs. 19, 20, 21). The single flagellum (Fig. 19) arises near it but not from it. A basal granule (Figs. 22, 33, 34) is present at or near the origin of the flagellum. Chromidia are present as scattered granules in the body (Figs. 28, 32, 33).
(6) The post-flagellate stage is the form assumed by the parasite for life outside the body of the host. Preceding encystment, the organism divides twice longitudinally, giving rise to four daughter forms (Pl. V, Figs. 51–54) each of which ultimately loses its flagellum, rounds itself off and forms a cyst (Figs. 57–68). These cysts are from 2·5μ to 4·5μ long and from l·4μ to 2·6μ, broad. They occur in the rectum of Nepa cinerea and are voided with the faeces, being ingested later by other bugs.
(7) Longitudinal division is the common method of multiplication of H. jaculum. The flagellum may divide precociously, but usually division is initiated by constriction of the blepharoplast (Pl. V, Fig. 37) almost simultaneously with division of the flagellum and followed by that of the nucleus (Figs. 39, 40). A split occurs (Figs. 40–42) and the active movements of the two flagella aid in the divergence of the daughter organisms (Figs. 43, 44), which ultimately separate.
(8) I have no evidence whatever for ascribing sex to any form of Herpetomonas, but consider the occurrence of long and short and of thin and stout forms to be explicable as the results of growth and division. Also, I have shown experimentally that richly granular protoplasm is the result of a physiological condition and is not necessarily fixed as an attribute of the female sex.
(9) One mode of infection has been proved experimentally in the laboratory and also observed at the breeding grounds of the Nepa. Cysts voided in infected faeces are swallowed by other Nepa in the adult and nymphal stages. The crops of such nymphs on dissection were found to contain cysts, whereas no flagellates were present in other parts of the gut, so that primary infection occurred here in the crops of the nymphs.
Cannibalism of Nepa cinerea whereby other Nepa are devoured is also responsible for the spread of H. jaculum.
I have no definite evidence of hereditary infection, although I have found flagellate and post-flagellate forms (Pl. V, Figs. 46–49) in the ovaries of the host. The parasites were not found in the eggs. The occurrence of parasites in the ovaries may be regarded as a stage in the evolution of hereditary infection.
(10) Various environmental effects have been studied, the most important observation being that fresh food appears to stimulate the parasites and to cause their rapid division.
(11) The generic name Herpetomonas should be retained, as originally constituted, for parasites having but one flagellum and no undulating membrane (see pp. 383 et seq.).
(12) I wish to record the occurrence of a new species of Herpetomonas, H. vespae, from the alimentary tract of the hornet, Vespa crabro.
Observations on Theileria parva, the Parasite of East Coast Fever of Cattle
- George H. F. Nuttall, H. B. Fantham, Annie Porter
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- Parasitology / Volume 2 / Issue 4 / December 1909
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- 06 April 2009, pp. 325-340
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Although a good deal has been written about East Coast Fever in cattle, the literature relating thereto contains very little direct information regarding the parasite which stands in causal relation to the disease. Robert Koch (1898), who was the first to observe the parasite in cases of East Coast Fever occurring in German East Africa, regarded it as but a variety of Piroplasma bovis (= bigeminum) and described the disease as Texas Fever. Theiler (1904) was the first to distinguish clearly East Coast Fever from Redwater. He stated that “the disease has nothing to do with Texas Fever or Redwater; it is a new disease due to a parasite different to the one found in Texas Fever.” Koch (1903—1904), who gave the disease its distinctive name, reached the same conclusions as Theiler. The investigations of Theiler (1904) established the following facts: Cattle which are immune to Redwater are susceptible to East Coast Fever. East Coast Fever is not communicable by blood inoculations (30 experiments, wherein 5 to 2000 c.c. of East Coast Fever blood were inoculated). He noted the absence of haemoglobinuria in the majority of animals affected with East Coast Fever, its presence in the majority of the animals affected with Redwater. He found that in most cases of East Coast Fever, there was no appreciable decrease in the number of red blood corpuscles, this being in marked contrast to what is observed in Redwater. Theiler noted that cattle might harbour both the parasites of Redwater (P. bovis) and those of East Coast Fever (bacillary forms = T. parva). The former generally appeared in the blood “only towards the end of the fever reaction in East Coast Fever,” being previously latent in the animals which had been “salted” against Redwater. He distinguished “two groups of piroplasmosis,” the inoculable (Redwater, canine and equine piroplasmosis) and the uninoculable (East Coast Fever) by injection of infected blood. The parasites in the latter are much smaller than in the former. He named the parasites of East Coast Fever Piroplasma parvum. Theiler distinguished the parasite of East Coast Fever from P. bovis because of the frequent occurrence of bacillary forms and the minute size of the parasite, but he nevertheless retained the new parasite in the genus Piroplasma.
The Leucocytozoa, a Rejoinder to Mr C. M. Wenyon
- Annie Porter
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- Parasitology / Volume 3 / Issue 2 / July 1910
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- 06 April 2009, pp. 239-244
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In the last number of Parasitology (Vol. iii. No. 1) Mr Wenyon has taken exception to an article of mine on the Leucocytozoa, published in Science Progress, October, 1909. It has been a matter of wonder to many protozoologists as well as to myself, why Mr Wenyon did not reply to my article in Science Progress itself, and thereby appeal to the readers whom he accuses me of having misled, for he states (Parasitology, p. 65) that my “survey of the group is inaccurate and contradictory.”
Some Haematozoa observed in vertebrates in eastern Canada
- H. B. Fantham, Annie Porter, L. R. Richardson
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- Parasitology / Volume 34 / Issue 2 / July 1942
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- 06 April 2009, pp. 199-226
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Some new species of Mastigophora and Sporozoa and a Microfilaria, parasitic in fish, frogs and toads in eastern Canada, are described and illustrated.
Trypanosoma percae n.var. canadensis from the yellow perch, Perca flavescens, is monomorphic, smaller, with a shorter, broader body and shorter free flagellum than Trypanosoma percae from European Perca fluviatilis. Trypanosoma myoxocephali n.sp. from the longhorn sculpin, Myoxocephalus octodecimspinosus, is small, with a narrow undulating membrane. It is the first trypanosome to be recorded from Myoxocephalus. Trypanosoma lavalia n.sp. from Bufo americanus is delicate, with a prominent undulating membrane with two myonemes. Trypanosoma gaumontis n.sp. from Bufo americanus is small, crook-like, with undulating membrane with deep folds and one myoneme very-near the bordering flagellum. There is no free flagellum. Trypanosoma montrealis n.sp. from Bufo americanus is long and sinuous, with very short free flagellum and without chromatoid granules in the cytoplasm.
Trypanosoma rotatorium (Mayer) is described from Rana catesbiana from eight sites, R. clamitans from three sites, and R. pipiens from three sites in Quebec Province. Trypanosoma inopinatum Ed. & Et. Sergent is recorded from Rana catesbiana and R. pipiens, A form similar in dimensions and morphology except for a much shorter free flagellum has been found in R. catesbiana from St Eustache.
Spirochaeta manitoui n.sp. is described from the blood of Rana catesbiana from Lake Manitou.
Lankesterella canadensis n.sp. from Rana catesbiana from Montreal and Lake Manitou is described and illustrated. Intracorpuscular forms have polar vacuoles, schizogony occurs in endothelial cells of the blood vessels of the liver and kidney, and multinucleate oocysts have been observed.
Haemogregarina myoxocephali n.sp. from the longhorn sculpin, Myoxocephalus octo-decimspinosus, and Haemogregarina urophysis n.sp. from the white hake, Urophysis tenuis, are described. Two other haemogregarines sens lat. from species of Rana and Bufoamericanus are described, Haemogregarina aeglifini Henry is recorded from a new host, Gadus callarias from off Labrador, Haemogregarina platessae Lebailly from Pseudopleuronectes americanus and Haemogregarina bigemina Laveran & Mesnil from the eel pout, Zoarces angularis, the hosts being new.
Plasmodium catesbiana n.sp. from Rana catesbiana from the Back River, Montreal, is a small species, with ‘signet ring’ and amoeboid trophozoites, schizonts with up to eight merozoites clustered round coarse pigment granules and gametocytes showing slight sexual dimorphism. Plasmodium bufonis n.sp. occurs in Bufo americanus from Laval des Rapides. The schizonts are large, oval, and give rise to eight merozoites arranged en barillet, the pigment usually being at one pole. Possibly micro- and macromerozoites may be produced. Macrogametocytes are oval and deep-staining; microgametocytes are vermicular. Both have pigment.
A haemosporidian, different from but probably allied to Haemogregarina bigemina, is described from the black sea bass, Centropristis striatus.
Haemoproteus laurentiae n.sp. occurs in Bufo americanus from the banks of the St Lawrence at Montreal South and at Lake Manitou. Its pigment is characteristic, consisting of rod-like or bacilliform distributed granules. Haemoproteus lavalia n.sp. from Bufo americanus, from Laval des Rapides, has pigment restricted to curved bands of rounded to somewhat angular granules. Uninucleate parasites have been observed in extremely few endothelial cells of the lungs. Haemoproteus lanoraiea n.sp. from Bufo americanus, from Lanoraie, has very pale yellow to light brown pigment granules, densely crowded at one pole and forming a compact granular cap. Oval parasites have been found in endothelial cells of the lungs.
Leucocytozoon salvelini n.sp., parasitic in the leucocytes of the speckled trout, Salve-linus fontinalis, is described.
Dactylosoma salvelini n.sp., parasitic in Salvelinus fontinalis from a Laurentian stream, is the second species of Dactylosoma to be described and the third to be notified from fish. It has fan- to wedge-shaped schizonts producing eight merozoites. Its gametocytes are not markedly different from one another in shape but differ in cytoplasmic staining and in nuclear structure. Dactylosoma sylvatica n.sp., parasitic in Rana sylvatica from near Quebec City, produces eight merozoites and has oval and reniform gametocytes.
The morphology of a Microfilaria from Rana sylvatica is described.
The effects of the Protozoa on the host cells are described for each organism, and some differential leucocyte counts for comparable normal and parasitized Amphibia are given in the concluding section.
Some remarks on the genera Crithidia, Herpetomonas and Trypanosoma
- Annie Porter
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- Journal:
- Parasitology / Volume 4 / Issue 1 / March 1911
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- 06 April 2009, pp. 22-23
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In this brief note it is not my intention to enter into detailed criticism, but merely to express my surprise and that of other proto-zoologists, that the personal opinions of the Recorder should be allowed insertion in the Zoological Record (1909) which is also the International Catalogue of Zoological Scientific Literature. Against this procedure I beg to record an emphatic protest.
The Morphology and Life-history of Crithidia gerridis, as found in the British Water-Bug, Gerris paludum
- Annie Porter
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- Parasitology / Volume 2 / Issue 4 / December 1909
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- 06 April 2009, pp. 348-366
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(1) Crithidia gerridis occurs in the alimentary tract of Gerris fossarwm, Microvelia and Perittopus sp. found in Madras. It is now recorded from the British water-bug, Gerris paludum, for the first time.
(2) The parasite occurs throughout the alimentary tract, in the ovaries and in the faeces of its host.
(3) There are three phases in the life-history of Crithidia gerridis, a pre-flagellate stage (Pl. IV, Figs. 1–10), a flagellate stage, and a post-flagellate stage (Figs. 64–69), the latter being adapted for life outside the body of the host, and for cross-infection.
(4) The adult flagellate has an elongate body, and possesses a large oval or round nucleus. There is also a smaller, usually rod-like mass of chromatin, the blepharoplast, near to which the flagellum arises. The flagellum may be as long again as the body, and is attached to it by a narrow, undulating membrane, in which myonemes are present (Figs. 22–46).
(5) The movements of the flagellated forms are characteristic; both the body and flagellum take part in the motion.
(6) The pre-flagellate forms are small, usually oval bodies, 3μ to 7μ long, and from 2μ to 4μ broad. Their nucleus often lies to one side and is round, the blepharoplast is rod-shaped. The flagellum grows out as a thin, delicate thread, in close contact with the body. The pre-flagellate phase of the parasite is found in the crop of the nymphs particularly, and also in the crop of the adults.
(7) The flagellate form has the general structure outlined in (4). The undulating membrane has indications of myonemes (Pl. IV, Figs. 41, 44, 45). The flagellum arises near a chromatic dot, the basal granule (Figs. 22, 30, 43). In the nucleus sometimes eight large chromatic masses may be present, or the grains may be very small. The nucleus on the whole is of the vesicular type. The blepharoplast is usually anterior to the nucleus, only very occasionally is it lateral. Chromidia are scattered in the endoplasm of the parasite (Figs. 26, 39, 46).
(8) The post-flagellate stage is a preparation for extra-corporeal life. The parasites divide in the rectum, lose their flagella, round themselves off and form a thin gelatinous cyst wall that rapidly hardens (Figs. 68, 69). These small cysts pass out with the faeces of the host.
(9) Longitudinal division is the chief method of multiplication. It may occur in all phases of the life-history and may be equal or sub-equal. The blepharoplast usually constricts first and division of it and of the flagellum follow one another very rapidly, division of the membrane follows, and then that of the body. The daughter halves gradually diverge and finally separate. In pre-flagellate division, rosettes may be formed by several rapid, repeated, longitudinal divisions (Fig. 20). The fully flagellated individuals first divide into two and repeated division may result in rosettes, but these very rapidly break up. Aggregation rosettes of mature flagellates are, however, extremely common (Fig. 47).
(10) The mode of infection is a casual one, the young nymphs taking up faeces containing crithidian cysts from the leaves of water plants.
(11) The parasite is purely a parasite of insects, occurring in two species of Gerris, G. fossarum and G. paludum. The systematic position of the parasite is near the Trypanosomes in the family Trypanosomatidae.
(12) There is much variation of form exhibited by the adult flagellate. Some of the very long parasites (Pl IV, Figs. 39, 44–46). appear to be peculiar to the Crithidia found in the gut of G. paludum, and have not been figured before so far as I know. This polymorphism needs careful attention, and is very confusing if only isolated stages of the parasite are studied. A similar remark applies to other crithidial and herpetomonad forms.
Some more myxosporidia observed in Canadian fishes
- H. B. Fantham, Annie Porter, L. R. Richardson
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- Parasitology / Volume 32 / Issue 3 / August 1940
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- 06 April 2009, pp. 333-353
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Seven species of marine fishes and three of fresh or brackish water Canadian fishes have yielded new or known Myxosporidia. The marine fishes were from St Andrews, New Brunswick and Halifax, Nova Scotia, places 250–275 miles apart by sea, and from the Labrador coast. The brackish and freshwater fishes were obtained in Montreal and the Salmon River, Nova Scotia.
Descriptions and illustrations are given of the morphology of five new species of Myxosporidia: Ceratomyxa urophysis, Myxoproteus myoxocephali, Myxidium myoxocephali, Myxosoma diaphana and Henneguya amiae.
Chloromyxum leydigi Mingazzini, C. granulosum Davis, Myxidium lieberkuhni Bütschli, Myxidium gadi Georgévitch and Zschokkella hildae Auerbach are recorded from new piscine hosts in Canada.
Some effects of the Myxosporidian infections, both macroscopic and microscopic, on their hosts are considered. Comparison of the effects of similar infections of Myxosporidia on allied fishes in Normandy and Eastern Canada has shown a general similarity between them.
The economic importance of some Myxosporidian infections of the edible fish examined is shown by parasitism of the cod, haddock and sculpin. Amia calva is also used for food in Montreal. The possibility of edible fishes acquiring Myxosporidian infections by way of their food is noted, with reference to the host-specificity of the Myxosporidia of Fundulus heteroclitus described by Bond.
The influence of environment on and powers of adaptation to different habitats exhibited by certain Myxosporidia is discussed.
Some remarks are made on the zoogeographical distribution of certain Myxosporidia and their piscine hosts.
On the Natural Occurrence of Herpetomonads (Leptomonads) in Mice
- H. B. Fantham, Annie Porter
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- Journal:
- Parasitology / Volume 8 / Issue 1 / June 1915
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- 06 April 2009, pp. 128-132
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While engaged in experimental researches on the introduction of insect flagellates, belonging to the genera Herpetomonas and Crithidia, into vertebrates, we have recalled to mind some former observations of ours made in 1909. When examining the blood of mice artificially infected with the spirochaetes of relapsing fever in the Quick Laboratory, Cambridge, we observed flagellates in the peripheral blood of the mice. These flagellates, which were scanty, were studied in fresh preparations by us and drawings of the organism were made with the camera lucida. Some of these drawings are now reproduced, together with others made by us subsequently. The flagellates were also observed by Professor Nuttall and his laboratory assistant, Mr B. G. Clarke, and we were unanimously agreed that the flagellates belonged to the genus Herpetomonas, or Leptomonas as some have since preferred to call it. The significance of the presence of herpetomonads in the blood of mice was very puzzling at the time, and pressure of other work prevented the subject being followed up. During 1911 and 1912, these flagellate organisms have been seen by all of us, but they were always evanescent and could not be found in fixed and stained preparations. The parasites were seen on different occasions in three mice altogether.
Amoeba chironomi, nov. sp., Parasitic in the Alimentary Tract of the Larva of a Chironomus
- Annie Porter
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- Journal:
- Parasitology / Volume 2 / Issue 1-2 / May 1909
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- 06 April 2009, pp. 32-41
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Amoeba chironomi, nov. sp., is distributed through practically the entire length of the digestive tract of the larva of Chironomus.
The body of A. chironomi varies from 15μ, to 18μ in length and from 10μ. to 12μ in breadth. The single pseudopodium may reach 15μ in length; one pseudopodium only is usually present.
Ectoplasm and endoplasm are well differentiated. A nucleus and a contractile vacuole are present. Food vacuoles are rare. The contractile vacuole resembles an iris diaphragm, consisting of a series of fine, curved, radiating canaliculi, opening into a central space. The excretory products are faintly reddish in colour. The presence of a contractile vacuole is uncommon in parasitic Amoebae.
The nucleus is poor in chromatin. A nucleolus is present.
A. chironomi is highly sensitive to the degree of concentration of the medium in which it lives. Very slight increase in density causes the organism to encyst.
Encystment occurs in the rectum of the host, and the cysts are voided with the faeces. The cysts are from 12μ. to 20μ long and from 9μ broad. The process of encystment is rapid.
The method of cross-infection of the host is probably a “casual” one, viz. by the mouth.
Some Myxosporidia found in certain freshwater fishes water fishes in Quebec province, Canada1
- H. B. Fantham, Annie Porter, L. R. Richardson
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- Journal:
- Parasitology / Volume 31 / Issue 1 / April 1939
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- 06 April 2009, pp. 1-77
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The Province of Quebec provides a magnificent field for fresh-water faunistic and ecological research on account of its numerous rivers and lakes. Investigations in ecology and ecological parasitology by the authors have revealed a rich fauna in the areas described herein.
Examinations of fourteen species of fresh-water fish have produced twenty-eight species of Myxosporidia, of which twenty-five are new and three have been already described. The existence of races or strains or varieties of some of the forms is demonstrated.
Descriptions and illustrations are given of twenty-eight Myxosporidia found by the authors in fresh-water fishes of Quebec Province. The new species include: Sphaerospora notropis, Myxidium percae, Zschokkella salvelini, Myxosoma notropis, M. commersonii, M. orbitalis, M. pfrille, M. media, M. ellipticoides, M. parellipticoides, Myxobolus poecilichthidis, M. dentium, M. percae, M. rhinichthidis, M. notropis, M. catostomi, M. couesii, M. hybo-rhynchi, M. subcircularis, M. transversalis, M. grandis, Henneguya fontinalis, H. fontinalis var. notropis, H. percae, H. salmonis and H. esocis. Myxosoma catostomi Kudo, Myxobolus conspicuus Kudo and M. ovoidalis Fantham are described from Canadian fishes. Details are given of a series of races, strains or varieties of Thelohanellus notatus Mavor, of Myxobolus catostomi, of M. notropis and of Henneguya fontinalis from other than the original host fish.
The pathology of the myxosporidian infections from the many different situations in the hosts is discussed. Unusual sites of infection are the palatine teeth of Esox maskinongy with Myxobolus dentium and the iris of the eye of Couesius plumbeus with Myxobolus couesii.
In connexion with the economic importance of the Myxosporidia found in Quebec fishes, the destruction of young fish, alteration of the character of the fauna dependent on the same, human food supply, possible epizootics in hatcheries and possible cross-infection of game fishes and other fishes of economic importance are considered. The immediate danger is not great; it is the future that may be imperilled.
Influence of nutrition on reproduction in laboratory rodents
- Annie M. Brown, Margaret J. Cook, W. Lane-Petter, G. Porter, A. A. Tuffery
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- Proceedings of the Nutrition Society / Volume 19 / Issue 1 / March 1960
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- 28 February 2007, pp. 32-37
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Looking Backward, Looking Forward: MLA Members Speak
- April Alliston, Elizabeth Ammons, Jean Arnold, Nina Baym, Sandra L. Beckett, Peter G. Beidler, Roger A. Berger, Sandra Bermann, J.J. Wilson, Troy Boone, Alison Booth, Wayne C. Booth, James Phelan, Marie Borroff, Ihab Hassan, Ulrich Weisstein, Zack Bowen, Jill Campbell, Dan Campion, Jay Caplan, Maurice Charney, Beverly Lyon Clark, Robert A. Colby, Thomas C. Coleman III, Nicole Cooley, Richard Dellamora, Morris Dickstein, Terrell Dixon, Emory Elliott, Caryl Emerson, Ann W. Engar, Lars Engle, Kai Hammermeister, N. N. Feltes, Mary Anne Ferguson, Annie Finch, Shelley Fisher Fishkin, Jerry Aline Flieger, Norman Friedman, Rosemarie Garland-Thomson, Sandra M. Gilbert, Laurie Grobman, George Guida, Liselotte Gumpel, R. K. Gupta, Florence Howe, Cathy L. Jrade, Richard A. Kaye, Calhoun Winton, Murray Krieger, Robert Langbaum, Richard A. Lanham, Marilee Lindemann, Paul Michael Lützeler, Thomas J. Lynn, Juliet Flower MacCannell, Michelle A. Massé, Irving Massey, Georges May, Christian W. Hallstein, Gita May, Lucy McDiarmid, Ellen Messer-Davidow, Koritha Mitchell, Robin Smiles, Kenyatta Albeny, George Monteiro, Joel Myerson, Alan Nadel, Ashton Nichols, Jeffrey Nishimura, Neal Oxenhandler, David Palumbo-Liu, Vincent P. Pecora, David Porter, Nancy Potter, Ronald C. Rosbottom, Elias L. Rivers, Gerhard F. Strasser, J. L. Styan, Marianna De Marco Torgovnick, Gary Totten, David van Leer, Asha Varadharajan, Orrin N. C. Wang, Sharon Willis, Louise E. Wright, Donald A. Yates, Takayuki Yokota-Murakami, Richard E. Zeikowitz, Angelika Bammer, Dale Bauer, Karl Beckson, Betsy A. Bowen, Stacey Donohue, Sheila Emerson, Gwendolyn Audrey Foster, Jay L. Halio, Karl Kroeber, Terence Hawkes, William B. Hunter, Mary Jambus, Willard F. King, Nancy K. Miller, Jody Norton, Ann Pellegrini, S. P. Rosenbaum, Lorie Roth, Robert Scholes, Joanne Shattock, Rosemary T. VanArsdel, Alfred Bendixen, Alarma Kathleen Brown, Michael J. Kiskis, Debra A. Castillo, Rey Chow, John F. Crossen, Robert F. Fleissner, Regenia Gagnier, Nicholas Howe, M. Thomas Inge, Frank Mehring, Hyungji Park, Jahan Ramazani, Kenneth M. Roemer, Deborah D. Rogers, A. LaVonne Brown Ruoff, Regina M. Schwartz, John T. Shawcross, Brenda R. Silver, Andrew von Hendy, Virginia Wright Wexman, Britta Zangen, A. Owen Aldridge, Paula R. Backscheider, Roland Bartel, E. M. Forster, Milton Birnbaum, Jonathan Bishop, Crystal Downing, Frank H. Ellis, Roberto Forns-Broggi, James R. Giles, Mary E. Giles, Susan Blair Green, Madelyn Gutwirth, Constance B. Hieatt, Titi Adepitan, Edgar C. Knowlton, Jr., Emanuel Mussman, Sally Todd Nelson, Robert O. Preyer, David Diego Rodriguez, Guy Stern, James Thorpe, Robert J. Wilson, Rebecca S. Beal, Joyce Simutis, Betsy Bowden, Sara Cooper, Wheeler Winston Dixon, Tarek el Ariss, Richard Jewell, John W. Kronik, Wendy Martin, Stuart Y. McDougal, Hugo Méndez-Ramírez, Ivy Schweitzer, Armand E. Singer, G. Thomas Tanselle, Tom Bishop, Mary Ann Caws, Marcel Gutwirth, Christophe Ippolito, Lawrence D. Kritzman, James Longenbach, Tim McCracken, Wolfe S. Molitor, Diane Quantic, Gregory Rabassa, Ellen M. Tsagaris, Anthony C. Yu, Betty Jean Craige, Wendell V. Harris, J. Hillis Miller, Jesse G. Swan, Helene Zimmer-Loew, Peter Berek, James Chandler, Hanna K. Charney, Philip Cohen, Judith Fetterley, Herbert Lindenberger, Julia Reinhard Lupton, Maximillian E. Novak, Richard Ohmann, Marjorie Perloff, Mark Reynolds, James Sledd, Harriet Turner, Marie Umeh, Flavia Aloya, Regina Barreca, Konrad Bieber, Ellis Hanson, William J. Hyde, Holly A. Laird, David Leverenz, Allen Michie, J. Wesley Miller, Marvin Rosenberg, Daniel R. Schwarz, Elizabeth Welt Trahan, Jean Fagan Yellin
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- PMLA / Publications of the Modern Language Association of America / Volume 115 / Issue 7 / December 2000
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- 23 October 2020, pp. 1986-2078
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- December 2000
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