Studies on the distribution and site location ofNippostrongylus brasiliensiswithin the small intestine of laboratory rats

Parasitology ◽  
1970 ◽  
Vol 61 (3) ◽  
pp. 449-460 ◽  
Author(s):  
Thomas J. W. Alphey
Keyword(s):  
Small Intestine ◽  
Primary Infection ◽  
Sexual Attraction ◽  
Adult Population ◽  
Migratory Behaviour ◽  
Fourth Stage ◽  
Site Location ◽  
Laboratory Rats ◽  
Anterior Half ◽  
Normal Site

The distribution ofN. brasiliensiswithin the small intestine of rats, following a primary infection, is described.The fourth stage larvae were found to inhabit the sections later parasitized by the adult population.Both the larval and adult worms were found to be confined to the anterior half of the small intestine. This aggregation is believed to be under the influence of stimuli (factor(s) 1), present in the lumen of the host gut.The adult worms also clumped within the already confined worm population. This behaviour is thought to be due to intrinsic behaviour patterns of the worm, sexual attraction and thigmokinesis.Larval and adult worms were surgically transferred to points, at varying distance from the ‘normally’ inhabited region, in the small intestine of fresh recipient rats. The resulting migratory behaviour of the worms was studied.The worm populations resulting from both the larval and the adult transfers showed the ability to recognize that they were in the wrong position of the small intestine and to be able to orientate, migrate and locate the ‘normal’ site.

The distribution of a primary infestation of Nippostrongylus brasiliensis in the small intestine of laboratory rats

Parasitology ◽  
1965 ◽  
Vol 55 (2) ◽  
pp. 313-324 ◽  
Author(s):  
M. R. Brambell
Keyword(s):  
Small Intestine ◽  
Adult Population ◽  
Relative Number ◽  
Egg Laying ◽  
Female Rats ◽  
Nippostrongylus Brasiliensis ◽  
Laboratory Rats ◽  
Male And Female Rats ◽  
Significant Difference ◽  
Reproducible Manner

The small intestine of rats was divided into twenty sections in a reproducible manner in order to study the distribution of Nippostrongylus brasiliensis by stretching it under a tension of 5g in adrenaline saline.A small but significant difference between the distribution of parasites in male and female rats was observed.As larvae had virtually ceased to reach the intestine by the fifth day all changes in distribution after that day were due to movements of the established adult population.Up to the twelfth day of a primary infestation the majority of the worms were found between the third and tenth sections, the population mode being in the fifth or sixth section. After the thirteenth day the number of worms in this region fell sharply.The female worms had not ceased from egg-laying by the time most of the worms were being rejected.The posterior half of the small intestine, i.e. the eleventh to twentieth sections, was not heavily parasitized, many of the worms seen being in passage to the anus.The first section was not parasitized until the seventh day, but thereafter remained parasitized until long after worms had disappeared from the more posterior sections.The relative number of male worms present increased as the infestation aged.Throughout the experiment the relative number of male worms present at the anterior end of the smaller intestine was higher than that at the posterior.Fourth-stage larvae were found chiefly in the sections that were later most heavily parasitized by adult worms.

Nippostrongylus brasiliensis: the distribution of primary worm populations within the small intestine of neonatal rats

Parasitology ◽  
1974 ◽  
Vol 68 (3) ◽  
pp. 339-345 ◽  
Author(s):  
D. Conwil Jenkins
Keyword(s):  
Small Intestine ◽  
Primary Infection ◽  
Host Immunity ◽  
Nippostrongylus Brasiliensis ◽  
Neonatal Rats ◽  
Young Rats ◽  
Privileged Site ◽  
Day By Day

When neonatal rats were exposed to a small (200 larvae) primary infection of Nippostrongylus brasiliensis the worms that became established in the intestine were found in the mid-jejunum on both the seventh and the fourteenth day after infection. By day 21 most of the worms had migrated to the duodenum where they remained subsequently.When similar rats were exposed to a heavy primary infection (1500 larvae) the worms were found to be distributed along the length of the duodenum and jejunum by the seventh day. By day 28, however, a proportion of worms equal to that formerly located in the jejunum had been expelled, leaving a population of about 300 worms in the duodenum.It is suggested that the increased longevity of those worms that survive the effects of host immunity is dependent on their location at the duodenal site. The possibility is raised that the duodenum may be an immunologically privileged site for N. brasiliensis in young rats.

The parasitic life-cycle of the swine kidney worm Stephanurus dentatus Diesing

1969 ◽  
Vol 17 (4) ◽  
pp. 607 ◽  
Author(s):  
AH Waddall
Keyword(s):  
Peritoneal Cavity ◽  
Migratory Behaviour ◽  
Fourth Stage ◽  
Mature Adult ◽  
Large Numbers ◽  
Third Stage ◽  
Parasitic Life Cycle ◽  
Patent Infection ◽  
Swine Kidney ◽  
Small And Large Intestine

Third-stage larvae of S. dentatus exsheath in and invade the tissues of a variety of animals. After oral infection of guinea pigs and pigs, third-stage larvae migrate principally from the small and large intestine via the portal blood, mesenteric lymphatics, and, to a lesser degree, the peritoneal cavity. Large numbers of larvae invade the liver, and it was shown that some larvae can escape from the liver and lungs. After infection via the skin, third-stage larvae migrate mainly to the lungs. There was evidence that some larvae undertake a tracheal migration from the lungs and subsequently penetrate the digestive tract. The third moult occurs in a variety of tissues, and by using transplantation techniques, it was shown that fourth-stage larvae are capable of extensive migration. The liver is the most suitable organ for the development of fourth-stage larvae and immature adult worms. The migratory behaviour of mature adult worms was studied by transplanting adult worms into the peritoneal cavity. One patent infection was established using this technique, but it appeared that most worms migrated randomly throughout the carcass.

Strongyloides ratti: 1. Parasitological observations on primary and secondary infections in the small intestine of rats

1977 ◽  
Vol 51 (4) ◽  
pp. 301-308 ◽  
Author(s):  
R. Moqbel ◽  
D. A. Denham
Keyword(s):  
Small Intestine ◽  
Primary Infection ◽  
Secondary Infection ◽  
Secondary Infections

ABSTRACTAdult Strongyloides ratti were expelled from the small intestine of rats starting 14—18 days after a primary infection. In a secondary infection very few adult worms developed and most of these were expelled before day 14. At the time of expulsion the worms migrated posteriorly in the intestine and their size decreased.

scholarly journals How Epstein-Barr Virus “Manipulates” The Tumoral Microenvironment in Hodgkin Lymphoma?

2019 ◽  
Vol 16 (2) ◽  
pp. 47-52
Author(s):  
Andrei Turbatu ◽  
Andrei Coliţă ◽  
Marilena Stoian ◽  
Ana-Maria Bordea ◽  
Mădălina Oprea ◽  
...  
Keyword(s):  
B Cell ◽  
Hodgkin Lymphoma ◽  
Primary Infection ◽  
Epstein Barr Virus ◽  
Adult Population ◽  
In Vivo Models ◽  
Benign Condition ◽  
Barr Virus ◽  
Epstein Barr

AbstractThe Epstein-Barr virus (EBV) is a gamma-herpesvirus that colonizes the B-cell system of its human host, allowing it to persist asymptomatically in the majority of the world’s adult population. In most people primary infection goes unnoticed, whereas in a minority of individuals, primary infection results in infectious mononucleosis (IM), a benign condition that almost always resolves after several weeks or months. However, EBV is also causally linked with a number of malignancies, including B-cell lymphomas, such as classical Hodgkin lymphoma (cHL).A proportion of patients with cHL harbor EBV within their tumor cells. Emerging evidence suggests that while EBV is able to subvert cellular processes to promote the growth and survival of HRS cells or their progenitors, mutations in key cell signalization pathways are probably required to do this when EBV is absent. The challenge is to unravel exactly how EBV and its latent genes contribute to the pathogenesis of cHL particularly with respect to how the virus co-operates with cellular genetic and epigenetic changes to drive transformation. It is hoped that the development of better in vitro and in vivo models of disease will reveal more fundamental aspects of EBV’s role in Hodgkin lymphoma pathogenesis and pave the way for targeted therapies for patients with EBV-positive cHL.

Induction of immunological tolerance in rats to Nippostrongylus brasiliensis infection

Parasitology ◽  
1967 ◽  
Vol 57 (3) ◽  
pp. 403-418 ◽  
Author(s):  
T. Kassai ◽  
I. D. Aitken
Keyword(s):  
Primary Infection ◽  
Worm Burden ◽  
Immunological Tolerance ◽  
Challenge Infection ◽  
The Other ◽  
Nippostrongylus Brasiliensis ◽  
Laboratory Rats ◽  
Successful Attempt ◽  
Other Hand

A successful attempt was made to induce immunological tolerance to N. brasiliensis in laboratory rats by exposing them to larval infections before the age of immunological maturity.The adult capacity of rats to eliminate a primary infection in 3 weeks and to acquire resistance to reinfection was developed by 5 weeks of age. On the other hand, primary infections of 250–660 larvae, originating before 4 weeks of age, survived in 61 of 83 rats up to 10 weeks. These rats were not resistant to challenge at 5 or 7 weeks of age, nor did the challenge infection undergo immune elimination. Such tolerance was evident even in rats whose primary worm burden was chemically abbreviated prior to challenge.It was not always possible to distinguish between tolerant and immune animals on the basis of egg output patterns. Suppression of egg output occurred even in tolerant rats harbouring relatively stable female populations.For immunological experiments on N. brasiliensis infection in rats, the determination of a ‘take ratio’ is advocated: (20 day take/10 day take) × 100. This ratio eliminates the error inherent in variability of takes and renders comparable the results of different experiments.The work was carried out in 1965 during tenure by one of us (T.K.) of an Exchange Scholarship under the British–Hungarian Cultural Agreement. Supervision by Professor W. Mulligan and the co-operation of colleagues in the Wellcome Laboratories are gratefully acknowledged.

Studies with Ostertagia circumcincta in Sheep. I. The epidemiology of mature adults and arrested larvae

1967 ◽  
Vol 41 (2-3) ◽  
pp. 137-150 ◽  
Author(s):  
P. S. James ◽  
I. L. Johnstone
Keyword(s):  
Adult Population ◽  
Post Mortem ◽  
Fourth Stage ◽  
Mature Adults

By means of egg counts, faecal cultures and post-mortem examinations of sheep the course of an infestation of Ostertagia circumcincta was followed from March until the following January in a flock of 100 twelve-months-old wethers at Wellington, N.S.W. The highest adult infestations and egg counts occurred in March and January, while during the winter months there was a continual accumulation of inhibited fourth stage larvae in the abomasal mucosa. The data suggest that the adult population observed in January arose from the inhibited population observed during the previous winter and that one of the factors controlling the development of the inhibited population was larval intake.

Temporal study of acquired resistance in infections of mice withGiardia muris

Parasitology ◽  
1983 ◽  
Vol 87 (3) ◽  
pp. 517-524 ◽  
Author(s):  
M. Belosevic ◽  
G. M. Faubert
Keyword(s):  
Small Intestine ◽  
Primary Infection ◽  
Acquired Resistance ◽  
Inbred Strains ◽  
Challenge Infection ◽  
Swiss Mice ◽  
Temporal Study ◽  
Inbred Strains Of Mice ◽  
Short Period ◽  
Giardia Muris

SummarySwiss CD-1 mice infected with cysts ofGiardia murisare protected against a challenge infection. A temporal study of this phenomenon was undertaken using two different approaches. First, the time needed for mice to acquire resistance was assessed by terminating the first infection using metronidazole on days 3, 6, 12, 24 or 48. These animals received a challenge infection 7 days later. Second, the duration of the protection was determined by giving mice a challenge infection on days 30, 60, 90, 120 or 150 after the primary infection. In all cases, a significant reduction in both cyst output and trophozoite numbers in the small intestine was observed after challenge. The reduction in cyst output following challenge was similar to the reduction in trophozoite numbers. The acquired resistance of some inbred strains of mice toG. muriswas similar to that of CD-1 Swiss mice. These results show that mice can acquire a significant resistance againstG. muriseven after a short period of contact with the parasite (3 days) and that the resistance may last up to 21 weeks.

scholarly journals ENTERAL INSUFFICIENCY COURSE SEVERITY DEGREES DIAGNOSTICS IN PERITONITIS BY SMALL INTESTINAL MICROSCOPIC IMAGES PHASE MAPING

2021 ◽  
pp. 25-30
Author(s):  
V. P. Polyovyy ◽  
R. I. Sydorchuk ◽  
S. P. Polyova ◽  
A. S. Palianytsia ◽  
I. G. Chepega
Keyword(s):  
Small Intestine ◽  
Phase Measurement ◽  
Measurement Data ◽  
Statistical Parameters ◽  
Logical Scheme ◽  
Microscopic Images ◽  
Laboratory Rats ◽  
Histological Sections ◽  
Insufficiency Syndrome ◽  
Polarization Phase

Summary. The aim is to determine the efficiency of diagnostics of the enteric insufficiency syndrome severity in peritonitis by phase mapping of microscopic images of histological sections of the laboratory rats’ small intestine. Material and methods. Seventy-eight white nonlinear rats of both sexes were selected, weighing from 180 to 220 g, underwent simulated mild, moderate and severe experimental peritonitis according to the standard method. Samples of optically thin histological sections of the small intestine of rats with different severity of the course of peritonitis were used as the research object. Results. As a result of the study, a structural and logical scheme for studying the effectiveness of differential diagnosis of the severity of peritonitis by means of statistical analysis of the structure of the distribution of phases of microscopic images of biological preparations of rats was developed, which helped to determine the relationships between the distribution of statistical parameters of the 1st–4th orders, which characterize phase maps depending on the severity of the peritonitis course. Conclusion. The revealed changes in the statistical structure of phase maps fully correlate with the measurement data for the polarization phase manifestations of the properties of the polycrystalline component of histological sections, both in the case of the phase measurement of polycrystalline blood films and the wall of the small intestine.

Anorexia in rats infected with the nematode, Nippostrongylus brasiliensis: experimental manipulations

Parasitology ◽  
2000 ◽  
Vol 120 (6) ◽  
pp. 641-647 ◽  
Author(s):  
J. G. MERCER ◽  
P. I. MITCHELL ◽  
K. M. MOAR ◽  
A. BISSETT ◽  
S. GEISSLER ◽  
...  
Keyword(s):  
Messenger Rna ◽  
Primary Infection ◽  
Arcuate Nucleus ◽  
Second Phase ◽  
Nippostrongylus Brasiliensis ◽  
Elevated Plasma ◽  
Laboratory Rats ◽  
Hypothalamic Arcuate Nucleus ◽  
Plasma Leptin ◽  
Cumulative Food Intake

Nippostrongylus brasiliensis induces a biphasic anorexia in laboratory rats, the first phase coincident with lung invasion (ca day 2) and the second when the worms mature in the intestine (ca day 8). Using the anthelminthic, mebendazole (MBZ), N. brasiliensis infections of the rat were eliminated between the first and second anorexic episodes. This intervention prevented the expression of the second phase of anorexia. Rats exposed to a second infection with N. brasiliensis, 3 weeks after the primary infection, exhibited only a first phase anorexic response which was not influenced by MBZ termination of the primary infection. The lower cumulative food intake and weight gain of all infected rats after 8 days of infection were accompanied by elevated plasma insulin and, in some individuals, by elevated plasma leptin, compared with uninfected controls and previously-infected MBZ-treated rats. Messenger RNA levels for neuropeptide Y were higher in the hypothalamic arcuate nucleus of 8-day infected rats than in recovering MBZ-treated animals. Inoculation of rats with heat-killed N. brasiliensis larvae failed to induce anorexia and did not alter the severity of biphasic anorexia on subsequent injection of viable larvae. The first anorexic episode is therefore dependent upon viable migrating larvae. The second phase of anorexia clearly requires the continuing presence of the parasite beyond the lung phase. Viable migrating larvae are also required to confer ‘resistance’ to reinfection.

Sign in / Sign up

Export Citation Format

Share Document