The effects of Fasciola hepatica on Lymnaea truncatula

Parasitology ◽  
1972 ◽  
Vol 65 (2) ◽  
pp. 359-369 ◽  
Author(s):  
J. K. M. Hodasi
Keyword(s):  
Rapid Growth ◽  
Egg Production ◽  
Fasciola Hepatica ◽  
Age Groups ◽  
Sharp Decline ◽  
General Belief ◽  
Functional Changes ◽  
Complete Cessation ◽  
Lymnaea Truncatula ◽  
Accelerated Growth

Among the functional changes observed in L. truncatula infected with F. hepatica were those of growth, reproduction and mortality. For the first 3 weeks after infection there was no difference between the growth of infected and uninfected groups of snails. Thereafter there was a temporary accelerated growth which occurred between the fourth and seventh weeks after infection. The onset of this period of rapid growth in the different age groups of infected snails coincided with the time of migration of the rediae into the hepatopancreas. Of more significance was the influence of infection on the reproduction of the snail. There was a sharp decline in oviposition 2–3 weeks after infection, followed by a complete cessation of egg production at the end of the fifth week. Once oviposition ceased, it was not resumed and there was no self-cure. Contrary to general belief, infected groups of L. truncatula have been found to live longer than the uninfected controls. With isolated snails, however, there was a tendency for the uninfected snails to live longer than the infected ones. The possible interpretation of the discrepancies between isolated and mass cultured snails are discussed. The hepatopancreas and the gonad (ovotestis) were the two structures directly affected by the infection. Establishment of the rediae in the hepatopancreas invariably resulted in parasitic castration.

France

2018 ◽  
Author(s):  
Philippe Askenazy ◽  
Bruno Palier
Keyword(s):  
Income Inequality ◽  
Labour Market ◽  
Rapid Growth ◽  
Household Income ◽  
General Trend ◽  
Age Groups ◽  
Wage Growth ◽  
The Elderly ◽  
Wage Setting ◽  
Rich Countries

This chapter describes France as apparently one of the few rich countries to have avoided a significant increase in income inequality in recent decades. However, stable average inequalities mask an asymmetric trend of income between age groups, the elderly improving their situation while the young see theirs worsening. Furthermore, it shows that behind this relatively still surface, a general trend of precarization of more and more ordinary workers is occurring. The importance of wage-setting processes and of regulation of the labour market is brought out, together with the way the tax and transfer systems have operated, in restraining the forces driving inequality upwards. Wage growth, while limited, has thus been reasonably uniform across the distribution and together with the redistributive system have kept household income inequality within bounds. However, in response to high unemployment both regulatory and tax–transfer systems have served to underpin the very rapid growth in precarious working over the last decade, representing a very serious challenge for policy.

scholarly journals Transcriptomic analysis reveals a role for the nervous system in regulating growth and development of Fasciola hepatica juveniles

2022 ◽  
Author(s):  
Emily Robb ◽  
Erin McCammick ◽  
Duncan Wells ◽  
Paul McVeigh ◽  
Erica Gardiner ◽  
...  
Keyword(s):  
Nervous System ◽  
Rapid Growth ◽  
Growth And Development ◽  
Liver Fluke ◽  
Fasciola Hepatica ◽  
Expression Profiles ◽  
Neuronal Signalling ◽  
Growth Development

Fasciola spp. liver fluke have significant impacts in veterinary and human medicine. The absence of a vaccine and increasing anthelmintic resistance threaten sustainable control and underscore the need for novel flukicides. Functional genomic approaches underpinned by in vitro culture of juvenile Fasciola hepatica facilitate control target validation in the most pathogenic life stage. Comparative transcriptomics of in vitro and in vivo maintained 21 day old F. hepatica finds that 86% of genes are expressed at similar levels across maintenance treatments suggesting commonality in core biological functioning within these juveniles. Phenotypic comparisons revealed higher cell proliferation and growth rates in the in vivo juveniles compared to their in vitro counterparts. These phenotypic differences were consistent with the upregulation of neoblast-like stem cell and cell-cycle associated genes in in vivo maintained worms. The more rapid growth/development of in vivo juveniles was further evidenced by a switch in cathepsin protease expression profiles, dominated by cathepsin B in in vitro juveniles and then by cathepsin L in in vivo juveniles. Coincident with more rapid growth/development was the marked downregulation of both classical and peptidergic neuronal signalling components in in vivo maintained juveniles, supporting a role for the nervous system in regulating liver fluke growth and development. Differences in the miRNA complements of in vivo and in vitro juveniles identified 31 differentially expressed miRNAs, notably fhe-let-7a-5p , fhe-mir-124-3p and, miRNAs predicted to target Wnt-signalling, supporting a key role for miRNAs in driving the growth/developmental differences in the in vitro and in vivo maintained juvenile liver fluke. Widespread differences in the expression of neuronal genes in juvenile fluke grown in vitro and in vivo expose significant interplay between neuronal signalling and the rate of growth/development, encouraging consideration of neuronal targets in efforts to dysregulate growth/development for parasite control.

scholarly journals CAN STATURE, ABDOMINAL PERIMETER AND BMI INDEX PREDICT POSSIBLE CARDIOMETABOLIC RISKS IN FUTURE OBESITY?

2020 ◽  
Vol 33 (2) ◽  
Author(s):  
Ricardo Wallace das Chagas LUCAS ◽  
Paulo Afonso Nunes NASSIF ◽  
Fernando Issamu TABUSHI ◽  
Denise Serpa Bopp NASSIF ◽  
Bruno Luiz ARIEDE ◽  
...  
Keyword(s):  
Age Groups ◽  
Abdominal Circumference ◽  
Fat Percentage ◽  
Height Measurement ◽  
Men And Women ◽  
Functional Changes ◽  
Abdominal Perimeter ◽  
Cardiometabolic Risks ◽  
The Aesthetic ◽  
The Individual

ABSTRACT Background: Obesity changes the anatomy of the patient. In addition to the aesthetic change, the high percentage of fat determines evident functional changes. Anthropometric normality in measuring abdominal circumference and height can serve as a basis for measuring cardiometabolic risks of obesity. Aim: To verify if it is possible to determine parameters of normality between waist and height in people with normal BMI and fat percentages, to serve as a basis for assessing risks for obesity comorbidities. Methods: A sample of 454 individuals with BMI and percentages of fat considered within the normal range was extracted. It was divided into age groups for both men and women between 18 and 25; 26 to 35; 36 to 45; 46 to 55; 56 to 65. A total of 249 men and 205 women were included. Results: Regarding the percentage of height as a measure of the abdominal perimeter, the total female sample had an average of 44.2±1.1% and the male 45.3%+1.5. For women, this percentage determined the equation of the waist-height ratio represented by X=(age+217) / 5.875, and for men X=(age+190.89) / 5.2222. “X” represents the percentage of the height measurement so that the individual falls into the category of adequate percentage of fat and BMI. Conclusion: Between the stature of adult men and women with normal fat percentage and BMI, there is a common numerical relationship, with is on average 44% for women and 45% for men.

scholarly journals Physiological adaptation of modern Ukrainian preschoolers

2013 ◽  
Vol 7 (4) ◽  
pp. 4-9
Author(s):  
Olha Fedortsiv ◽  
Nataliia Luchyshyn
Keyword(s):  
Cardiovascular System ◽  
Developmental Disorders ◽  
Age Groups ◽  
Individual Development ◽  
Physiological Adaptation ◽  
Rate Pressure Product ◽  
Noninvasive Methods ◽  
Functional Changes ◽  
Physical Burden ◽  
System Functioning

Introduction: High demands of modern social environment to the child’s individual development are connected with their health decline and wide variation of individual capabilities. Because of such inconsistency decreased functional abilities are being observed in preschoolers. It leads mainly to health problems and developmental disorders. Body adaptive properties are considered to be the integral indicator of health. Researches find high prevalence of the lack of adaptation among children of different age groups which might lead to low quality of life.Aim of the study: The aim of the research was to estimate preschooler’s cardiovascular system functioning and the adaptation abilities based on the examples of children from Tarnopol, Ukraine.Material and methods: 170 healthy preschoolers were among the participants of the research. Anthropometry and the assessment of some hemodynamic parameters were performed to draw conclusions about the level of their cardiovascular capacity.Results: Only 54.7% of the examined children reflect the satisfactory level of cardiovascular system adaptation. The deviations mainly result from high BMI, Rate Pressure Product and abnormal reaction of the autonomic nervous system after a squatting test.Conclusions: Simple noninvasive methods (functional changes index, pulse rate and blood pressure and the indicator of arteries’ pressure) help to identify children with reduced circulatory response to stress and physical burden.

scholarly journals Natural infection of Lymnaea truncatula by the liver fluke Fasciola hepatica in the Porma Basin, León, NW Spain

1991 ◽  
Vol 65 (1) ◽  
pp. 15-27 ◽  
Author(s):  
Y. Manga-Gonzalez ◽  
C. Gonzalez-Lanza ◽  
C. B. Otero-Merino
Keyword(s):  
Liver Fluke ◽  
Fasciola Hepatica ◽  
Natural Infection ◽  
Infection Prevalence ◽  
Average Intensity ◽  
Nw Spain ◽  
Chi Square ◽  
Monthly Average ◽  
Lymnaea Truncatula ◽  
Chi Square Test

ABSTRACTFor two years fortnightly malacological samplings were carried out to collect Lymnaea truncatula (Mollusca; Basommatophora) at five points in the upper and middle Porma river basin, León, Spain. The highest numbers of snails were collected in September, May and November. Of the 5486 molluscs examined, 11·41% harboured F. hepatica (Trematoda; Digenea) with an average intensity of 20·14. In general, the values of both infection prevalence and intensity increased with the size of the snails. It was in October when the highest figures for each parameter mentioned above were detected (18·73% and 28·48, respectively). The chi-square test showed statistically significant differences in relation to the infection prevalence among the groups of molluscs established according to: their length; the months in which they were collected; the sampling localities; monthly average ambient temperature; precipitation during the collection. Similarly, statistically significant differences were detected in the intensity of the infection among the groups of molluscs previously established, except for that based on the values of precipitation. Generally, parasites were found in the same snail at different stages of development. It seems that most mollusc infections occur in February–March and at the end of summer–beginning of autumn periods. The highest rate of rediae with mature cercariae ready to be shed were detected between September and December. Metacercariae in the grass samples were also observed at the end of autumn. For this reason, this period could be considered as the most suitable for infection of the definitive hosts to take place.

Investigation of Major Ecto-Parasite Affecting Backyard Chicken in Bishoftu Town, Ethiopia

2019 ◽  
pp. 1-9
Author(s):  
Wangelu Kebede ◽  
Keyword(s):  
Egg Production ◽  
Age Groups ◽  
Single Species ◽  
Poultry Production ◽  
Poultry Products ◽  
Exotic Breed ◽  
The Difference ◽  
Young Chicken ◽  
Pathogenic Agents ◽  
And Control

Backyard poultry production are considered as sources of meat and egg production. However, Parasites are among the main pathogenic agents, threatening the health of poultry and poultry products. The current study was conducted to investigate the prevalence of ectoparasite of poultry managed under backyard system started from November 2019 to April 2020 in Bishoftu town, surroundings of four kebeles; Babogaya, Danbi, 01kebele and 05 kebele in Oromia region South east of Finfinnee. 384 chickens of different age groups, both sexes and breeds were examined. Overall, 228/384 (59.4%) of chickens were infested with species of ectoparasites that mainly grouped into lice 141(36.7%), flea 79 (20.6%), and mite 8(2.1%). The prevalence of ectoparasite infection was 56(14.6%), 51(13.3%), 58(15.1%) and 63(16.4)% in Bishoftu town, Babogaya, Danbi, 01kebele and 05 kebele respectively, the difference in the prevalence of the parasites among difference kebeles were not statistically significant (P>0.05). The prevalence of ectoparasites infestation was higher in male 128(33.33%) chickens than females 100(26.04%) and higher in adult 150 (39.1%) than young chicken 78 (20.3%), high in local breeds 129(33.6%) than exotic breed 99 (25.8%). Seven species were identified with their attachments site, namely; menacanthus stremineus(13.3%) was found on skin, menopon gallinae(12.5%) was found on skin, thigh, feather and breast, goniodes gigas(5.5%) was found on skin and body feather, gonicotes gallinae (2.9%) was found on feather, lipeurus caponus(2.6%) was found on wing, skin, tail feather and a single species of flea(Echidnophaga gallinacae) 20.6% was found on eye, comb and wattle. while a single species of mite (ornithonyssus sylviarum) 2.1% was found on base of feather particularly, the vent area. In conclusion, infestation of chicken with ectoparasites was important constraint in poultry production sector. Associated with lack of attention with respect to hygienic system, treatment and control practices. Based on the results it could be suggested that, good management, biosecurity and the education of farmers could be a vital measure to keep free from ectoparasites and improve the productivity of the chicken.

Functional maturation of tactile sensory fibers in the kitten

1984 ◽  
Vol 52 (1) ◽  
pp. 74-85 ◽  
Author(s):  
D. G. Ferrington ◽  
M. O. Hora ◽  
M. J. Rowe
Keyword(s):  
Age Groups ◽  
Postnatal Period ◽  
High Frequencies ◽  
Functional Changes ◽  
Functional Maturation ◽  
Tactile Stimuli ◽  
Adult Cats ◽  
Skin Indentation ◽  
Sensory Fibers ◽  
Cutaneous Vibration

The maturation of tactile coding capacities was investigated in sensory fibers supplying the forelimb footpads in anesthetized kittens. Fibers were isolated by microdissection from the median or ulnar nerves of neonatal kittens (1st to 5th postnatal day) and kittens in the age categories 10-15, 25-30, 55-63, and 83-90 days. The use of quantitative, reproducible tactile stimuli, in particular, cutaneous vibration, and objective analytical procedures enabled response parameters to be quantified and compared at different ages with those of adult fibers. While three classes of myelinated tactile sensory fibers are associated with the footpads in adult cats, one of them slowly adapting (SA) and two, the rapidly adapting (RA) and pacinian corpuscle (PC) classes, showing pure dynamic sensitivity, this breakdown into three classes is not apparent until 10-15 days after birth. In all age groups, the SA fibers displayed responses that were graded depending on the magnitude of the skin indentation. However, in younger kittens (less than 25-30 days) plateau levels of response were sometimes attained over a narrow range (0.5 mm) of indentation. From 10-15 days, when RA fibers are identifiable, their sensitivity, as measured by absolute and 1:1 thresholds to cutaneous vibration, was independent of age at low vibration frequencies, less than or equal to 80 Hz. However, at high frequencies, e.g., 200 Hz, their thresholds appeared to decrease during the 1st postnatal month with a resulting expansion in their bandwidth of vibratory sensitivity. At their best frequency, around 30 Hz, RA fibers appear mature by 10-15 days in their capacity for encoding vibratory frequency information. The PC class of tactile afferents displayed the most striking functional changes with age. Their vibratory bandwidths, at 50-micron amplitude, expand from an upper limit of about 200-300 Hz in the neonate to mature values of about 800-1,000 Hz over a 2-mo postnatal period.(ABSTRACT TRUNCATED AT 400 WORDS)

Crowding effect on adult growth, pre-patent period and egg shedding of Fasciola hepatica

Parasitology ◽  
2006 ◽  
Vol 133 (4) ◽  
pp. 453-463 ◽  
Author(s):  
M. A. VALERO ◽  
M. DE RENZI ◽  
M. PANOVA ◽  
M. A. GARCIA-BODELON ◽  
M. V. PERIAGO ◽  
...  
Keyword(s):  
Rat Model ◽  
Egg Production ◽  
Fasciola Hepatica ◽  
Chronic Phase ◽  
Infection Intensity ◽  
Epidemiological Studies ◽  
Crowding Effect ◽  
Patent Period ◽  
Adult Growth

Fascioliasis pathogenesis depends on fluke burden. In human hyperendemic zones, individual infection intensities reach very high levels and the majority of infected subjects should be in the advanced chronic phase. The rat model offers a useful approach for pathological research in the advanced chronic period. The influence of infection intensity per rat on fluke development, pre-patent period and egg shedding (eggs/g faeces/worm) was analysed in 3 groups (I: 1–3 worms/rat; II: 4–6; III: 7–9). Ontogenetic trajectories of fluke body measures followed a logistic model. Results showed that when the burden increases, the maximum values of fluke measures decrease. The crowding effect is manifest when fluke measures approximate their maximums in the advanced chronic stage. The pre-patent period and egg production decrease when the burden increases. This means that measurements of eggs per gramme of faeces tend to underestimate the fluke burden. The present study demonstrates how to quantify the fascioliasis experimental rat model crowding effect on adult growth, pre-patent period and egg production. This quantification may be of great interest in epidemiological studies and in experimental research on the in vivo actions of different anthelminthic drugs and vaccines, pathology, immunology and resistance studies.

scholarly journals Aortae of Young Rats with Metabolic Syndrome Exhibit Enhanced Vasoconstrictor Activity Than Older Rats

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
R H Ali ◽  
N M B Gamil ◽  
A M Abdelrahman ◽  
M A Ahmed ◽  
G K Megahed ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Young Adult ◽  
Fasting Blood Glucose ◽  
Age Groups ◽  
Female Rats ◽  
Control Group ◽  
Albino Rats ◽  
Functional Changes ◽  
Vasoconstrictor Response ◽  
Nitrite Content

Abstract Background Metabolic syndrome (MetS) causes pathological remodeling of the heart and adjacent vessels. The functional changes in the big vessels in different age groups had not been fully delineated. Aim of the work The present study was planned to investigate aortic vasodilator and vasoconstrictor reactivity in young, adult and old female rats with MetS. Design: The experimental study was performed on 90 female albino rats randomized into 6 groups: young, adult and old rats with MetS and their respective control groups. Methods MetS was induced by feeding rats 41% fructose -containing diet and giving fructose solution (5 g fructose in 4 ml distilled water/day) by gavage in two sessions (2 ml/session). On the 8th week, all rats were sacrificed and were subjected to determination of body weight (BW), body mass index (BMI), absolute and relative visceral fat weight (VF), fasting blood glucose (FBG), plasma insulin (PI), homeostasis model of insulin resistance (HOMA-IR) and plasma lipid profile. All rats’ aortae were subjected to study of vascular reactivity to Potassium chloride (KCL), phenylephrine (PE) and acetyl choline (A.Ch) as well as estimation of nitrite content. Results On the 8th week of the study, all MetS groups developed criteria of metabolic syndrome as evidenced by the significant increase in final BW, BMI, absolute and relative VF weights, FBG, PI and HOMA-IR compared to their control group values. Also, MetS rat groups exhibited evident dyslipidemia in the form of significant increase in plasma levels of triglycerides, total cholesterol and significant decrease in HDL-cholesterol compared to their control group values. Aortae of young and adult MetS rat groups showed significant increase in their vasoconstrictor response to KCl and PE and decrease in A.Ch/KCL% and A.Ch/PE % compared to their controls, while old MetS rat group showed significantly increased vasoconstrictor response only to KCL compared to their controls. When compared to each other, young age MetS group had significantly higher vasoconstrictor response to PE compared to old MetS group despite comparable nitrite content. Conclusion Met.S causes functional vascular changes in all age groups with unexpectedly enhanced vasoconstrictor response in the young group compared to old.

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