Growth of single proglottides during early adult development of Hymenolepis nana

Parasitology ◽  
1989 ◽  
Vol 99 (1) ◽  
pp. 115-125
Author(s):  
H. Kumazawa ◽  
I. Fairweather
Keyword(s):  
Adult Development ◽  
Post Infection ◽  
Growth Curves ◽  
Fold Increase ◽  
Growth Patterns ◽  
Time Axis ◽  
Hymenolepis Nana ◽  
The Common ◽  
Rates Of Growth ◽  
Parallel Growth

SUMMARYThe growth of individual proglottides of Hymenolepis nana has been studied by measuring the width and length of the proglottides between days 3 and 8 post-infection in mice. Two sets of measurements were obtained. The first involved proglottides immediately posterior to the point of proglottis formation and proglottides at particular stages of development. For the second set, measurements were made of proglottides at certain positions in the worm, specifically the 20th, 100th and 200th proglottides, as counted from the posterior end of the worm. For proglottides at different stages in development, the width of a particular stage was greater in the later days of infection, while the length was almost constant. The length of newly-formed proglottides varied only slightly with time despite differences in the width and in the 3-fold increase in proglottis production that occurs between days 3 and 8 post-infection. The width of the 20th, 100th and 200th proglottides followed parallel growth curves that coincided with each other after an appropriate shift along the time axis. The more anterior the position of the proglottis, the greater was the width at the time of proglottis formation, and so its growth began later on the common growth curve. Growth in length of the 20th proglottis was at first faster than the 100th and 200th proglottides, but later slowed down to a level comparable with them, and the growth curves for the length of the three proglottides were very similar to each other. The rates of growth in the volume of the three proglottides were also estimated. The results are also discussed in relation to other approaches to the study of tapeworm growth and to factors that may be responsible for the growth patterns observed.

PATTERNS OF GROWTH IN HEIGHT AND WEIGHT FROM BIRTH TO EIGHTEEN YEARS OF AGE

PEDIATRICS ◽  
1959 ◽  
Vol 24 (5) ◽  
pp. 904-921
Author(s):  
Robert B. Reed ◽  
Harold C. Stuart
Keyword(s):  
Growth Curves ◽  
Growth Patterns ◽  
Individual Growth ◽  
Growth Spurt ◽  
Adolescent Growth Spurt ◽  
Wide Range ◽  
Basic Facts ◽  
The Individual ◽  
Rates Of Growth ◽  
Mature Size

In this report is displayed the range of variation observed in the growth curves of height and weight in a series of 134 children observed from birth to 18 years. For purposes of simplification the individuals have been classified on the basis of their rates of growth during three successive 6-year intervals. Even in terms of this crude classification several basic facts about individual growth patterns of height and weight are apparent. The wide range of differences between individuals applies not only to facts about size at specific ages but also to the pattern of change followed from age period to age period. The rate of growth during early childhood, i.e. before 6 years of age, is associated with, but not specifically predictive of, size at maturity and timing of the adolescent growth spurt. Individuals with rapid growth before 6 years of age tend to have large mature size and early adolescent growth spurt. It will be the objective of future reports from this research project to determine the manner in which the individual differences in growth demonstrated and classified here are related to aspects of physical development, to environmental influences such as dietary intake and to the level of health of the child.

Growth of Grey Kangaroos and the Reliablility of Age Determination from Body Measurements III. Interspecific Comparisions between Eastern and Western Grey Kangaroos, Macropus giganteus and M. fuliginosus

1984 ◽  
Vol 11 (1) ◽  
pp. 11 ◽  
Author(s):  
WE Poole ◽  
SM Carpenter ◽  
JT Wood
Keyword(s):  
Growth Models ◽  
Age Determination ◽  
Growth Patterns ◽  
Adult Size ◽  
Body Measurements ◽  
Foot Length ◽  
The Common ◽  
Rates Of Growth ◽  
Body Parameters

Seven body measurements were taken at regular intervals throughout life from both male and female eastern and western grey kangaroos. Evaluation of the reliability of criteria for determination of age and some aspects of the growth models for the two species were presented in earlier papers in this series. In this paper the common patterns and relationships between species in the growth characteristics of their body parameters are described and analysed. Comparison is made between species and sexes of rates of growth and size attained both within the pouch and following vacation of the pouch. Head, arm, leg and foot length were important discriminators, particularly when contrasted in various ways to summarize different body proportions. The insular form M.f. fuliginosus readily separated from the mainland forms, and M.f. ocydromus showed some differences which were related to its longer pouch life. Hybrid animals showed growth patterns intermediate to those of their parents. Sexual dimorphism in patterns ofgrowth was not detected during pouch life but was exhibited by all species after the young vacated the pouch and grew towards their full adult size.

Advantages of Complementary Stereo Images as Viewed with the Low-Temperature Field-Emission SEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1314-1315
Author(s):  
William P. Wergin ◽  
Eric F. Erbe
Keyword(s):  
Fold Increase ◽  
Horizontal Displacement ◽  
Three Dimensions ◽  
Stereo Image ◽  
Stereo Pair ◽  
Sem Micrograph ◽  
Left And Right ◽  
The Common ◽  
The Brain ◽  
Pair Analysis

The eye-brain complex allows those of us with normal vision to perceive and evaluate our surroundings in three-dimensions (3-D). The principle factor that makes this possible is parallax - the horizontal displacement of objects that results from the independent views that the left and right eyes detect and simultaneously transmit to the brain for superimposition. The common SEM micrograph is a 2-D representation of a 3-D specimen. Depriving the brain of the 3-D view can lead to erroneous conclusions about the relative sizes, positions and convergence of structures within a specimen. In addition, Walter has suggested that the stereo image contains information equivalent to a two-fold increase in magnification over that found in a 2-D image. Because of these factors, stereo pair analysis should be routinely employed when studying specimens.Imaging complementary faces of a fractured specimen is a second method by which the topography of a specimen can be more accurately evaluated.

scholarly journals Implementation and Evaluation of a Communication Strategy to Control Ragweed Pollen

2016 ◽  
Vol 5 (1) ◽  
pp. 87
Author(s):  
Celine Plante ◽  
Audrey Smargiassi ◽  
Francine Hubert ◽  
Sophie Goudreau
Keyword(s):  
Fold Increase ◽  
Ambrosia Artemisiifolia ◽  
Communication Strategy ◽  
Ragweed Pollen ◽  
Communication Intervention ◽  
Effective Measure ◽  
Land Owners ◽  
Before And After ◽  
Logistic Regressions ◽  
The Common

The common ragweed (<em>Ambrosia artemisiifolia</em>) is widespread in southwestern areas of Quebec, Canada. It is known to release large quantities of pollen from July through September, triggering allergic reactions such as rhinitis and generating significant costs for public health. The objective of this study was to implement and evaluate a communication intervention aimed at decreasing ragweed pollen. Selected lands with potential ragweed presence were visited twice, before and after the intervention, on three seasons in the East of the Montreal Island, Quebec. At the first visit done in 2010, 2011, and 2012, ragweed plots were located and measured; at the second visit in 2012, the measures were redone. Various numbers of communications were sent to owners of ragweed-infested lands that included explanations of health impacts of ragweed pollen and the importance of mowing. Mixed logistic regressions were used to test the effect of the number of communications on the mow. In the group that received four notices, a statistically significant three-fold increase in the proportion of land owners that had cut ragweed plots (OR = 3.20; 95 %CI: 1.16-8.84) was noted, compared to the group that received only one notice. For owners of vacant lands, the effect was somewhat more pronounced (OR = 3.82; 95%CI: 1.23-11.67). Nonetheless, the change from one to three communications showed no increase of mowing. In conclusion, the results of the present study suggest that communications and reminders of the importance of ragweed cut to landowners could be an effective measure to limit ragweed pollen.

A STUDY OF RATES OF GROWTH OF YORKSHIRE, LACOMBE, LANDRACE, AND CROSSBRED PIGS FROM BIRTH TO 200 LB

1964 ◽  
Vol 44 (3) ◽  
pp. 315-319
Author(s):  
J. M. Bell
Keyword(s):  
Growth Rates ◽  
Early Life ◽  
Growth Curves ◽  
Rates Of Growth ◽  
Similar Growth ◽  
Crossbred Pigs

Growth records were obtained from 12 research establishments across Canada for pigs fed according to current (1960–63) recommendations of nutrition and management. Growth curves showing age in days and weight in pounds are presented for the various breeds and crossbreds, for between-station comparisons, for comparison of upper and lower quartiles in purebred pigs, and for comparison of growth rates of purebreds with that of Yorkshires of 20 to 25 years ago.Age at 200 lb averaged from 152 to 187 days, among 10 stations for the Yorkshire breed. Pigs of each of the pure breeds reached 200 lb about 3 weeks earlier than that indicated in previous studies. Crossbred pigs of each of four different crosses grew more rapidly than average Yorkshires, some reaching 200 lb in 140 days and having gains in excess of 2.3 lb/day during the finishing period. Yorkshire, Lacombe, and Landrace pigs had similar growth curves. The upper quartile averaged 1.8 and the lower 1.4 lb/day gain between 100 and 200 lb weights. Slow-maturing pigs tended to be below average throughout life but differences in maturity between stations seemed to reflect differing rates of gain in early life, since finishing period gains were similar in 8 of 10 stations.

scholarly journals Evaluation of Putative Type II Toxin-Antitoxin Systems and Lon Protease Expression in Shigella flexneri Following Infection of Caco-2 Cells

2020 ◽  
Vol 15 (3) ◽  
Author(s):  
Erfan Kheradmand ◽  
Shabnam Razavi ◽  
Malihe Talebi ◽  
Mahmood Jamshidian
Keyword(s):  
Cell Line ◽  
Post Infection ◽  
Shigella Flexneri ◽  
Fold Increase ◽  
Expression Level ◽  
Bacterial Invasion ◽  
P Value ◽  
Lon Protease ◽  
Expression Levels ◽  
Pcr Method

: Shigella flexneri causes bacillary dysentery in developing countries. Due to recent reports regarding antimicrobial resistance in human S. flexneri, finding alternative therapeutics is of vital importance. Toxin-antitoxin (TA) systems have recently been introduced as antimicrobial targets owing to their involvement in bacterial survival in stress conditions and “persister” cell formation. In this study, the presence of four TA loci were studied in S. flexneri ATCC 12022. The presence of genes coding for the identified TA loci and Lon protease were confirmed by the PCR method using specific primers. Caco-2 cell lines were then infected with this standard strain, and 8 and 24 h post-infection, expression levels of genes coding for the studied TA loci, and Lon protease were evaluated using a real-time PCR method. Expression of mazF, GNAT (Gcn5-related N-acetyltransferase), yeeU, pfam13975, and Lon genes showed 5.4, 9.8, 2.3, 2.7, and 13.8-fold increase, respectively, 8 h after bacterial invasion of the Caco-2 cell line. In addition, the expression of the aforementioned genes showed 4.8, 10.8, 2.3, 3.7, and 16.8-fold increase after 24 h. The GNAT and lon genes showed significantly higher expression levels compared to the control (P value < 0.05). However, the increase in the expression level of yeeU was the same at 8 h and 24 h post-infection. In addition, mazF expression level showed a slight decrease at 24 h compared to 8h post-infection. Genes coding for GNAT and Lon protease showed a significantly higher expression after invading the Caco-2 cell line. Therefore, targeting GNAT or Lon protease can be taken into consideration for finding novel antimicrobial drug strategies. The exact functions and mechanisms of TA systems in S. flexneri isolates are suggested to be experimentally determined.

ANIMAL PARASITES AND HUMAN DISEASES

PEDIATRICS ◽  
1958 ◽  
Vol 22 (2) ◽  
pp. 380-384
Author(s):  
Paul C. Beaver
Keyword(s):  
Strongyloides Stercoralis ◽  
Hymenolepis Diminuta ◽  
Parasitic Infections ◽  
Hymenolepis Nana ◽  
Medical Problems ◽  
Laboratory Methods ◽  
Dipylidium Caninum ◽  
Laboratory Workers ◽  
The Common ◽  
Rats And Mice

PARASITES fall only roughly into the two categories implied in the title of this discussion. While a few of them are totally dependent upon human hosts, and some are able to develop only in other animals, a majority of the parasites commonly referred to as "parasites of man" are in reality parasites of other animals. In the latter group are such familiar examples as Trichinella, found in rats and many other animals, including pigs; Balantidium and some lesser protozoa of pigs; Toxoplasma, which occurs in many wild and domesticated animals. Trypanosoma cruzi, which is carried by a variety of animals, is the cause of Chagas' disease commonly seen in parts of South America and found recently in a child in Texas. Other examples include Isospora of undetermined hosts, possibly including the dog; Trichostrongylus species that commonly are found in sheep and goats; the small tapeworms, Hymenolepis nana and Hymenolepis diminuta, of rats and mice; and the common dog tapeworm, Dipylidium caninum. There are others whose endemicity in any area depends somewhat on the presence of suitable non-human hosts, and still others that are able to reach maturity in man but are rarely involved in medical problems because infection is acquired only by eating uncooked earthworms and insects. It might be mentioned, as a matter of interest, that occasionally other animals may acquire parasitic diseases from their human associates, as for example dysentery and diarrhea in dogs, caused by Entamoeba histolytica and Strongyloides stercoralis. In all of the above mentioned parasitic infections, diagnosis is usually based on conventional laboratory methods, and both clinical and laboratory workers are generally familiar with the problems presented by them.

Tracheal blood flow during spontaneous and mechanical ventilation of dry gases in sheep

1990 ◽  
Vol 69 (3) ◽  
pp. 1117-1122 ◽  
Author(s):  
D. A. White ◽  
G. H. Parsons
Keyword(s):  
Mechanical Ventilation ◽  
Blood Flow ◽  
Cardiac Output ◽  
Left Atrial ◽  
Bronchial Artery ◽  
Minute Ventilation ◽  
Fold Increase ◽  
Artery Blood Flow ◽  
The Common ◽  
Spontaneously Breathing

Tracheal blood flow increases greater than twofold in response to eucapnic hyperventilation of dry gas in anesthetized sheep. To determine whether this occurs at normal minute ventilation, we studied sheep in which tracheal blood flow was measured in response to humid and dry gas ventilation while 1) awake and spontaneously breathing and 2) anesthetized and intubated during isocapnic mechanical ventilation. In additional sheep, three tracheal mucosal temperatures were measured during humid and dry gas mechanical ventilation to measure airway tissue cooling. Tracheal blood flow was determined by use of a left atrial injection of 15-microns-diam radiolabeled microspheres. Previously implanted flow probes on the pulmonary artery and the common bronchial artery allowed continuous recording of cardiac output and bronchial blood flow. Tracheal blood flow in awake spontaneously breathing sheep was 10.8 +/- 5.6 (SD) ml.min-1.100 g wet wt-1 while humid gas was breathed, and it was unchanged with dry gas. In contrast, isocapnic ventilation of intubated animals with dry gas resulted in a 10-fold increase in blood flow to the most proximal two-ring tracheal segment compared with that seen while humid gases were spontaneously ventilated [101 +/- 75 vs. 11 +/- 6 (SD) ml.min-1.100 g-1, P less than 0.05]. Despite a 10-fold increase in proximal tracheal blood flow, there was no response in distal tracheal and bronchial blood flow, as indicated by no change in the common bronchial artery blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Growth Curve of Selectively Bred Tambaqui (Colossoma macropomum) Reared in Different Environments

2020 ◽  
Vol 8 (3) ◽  
pp. 585
Author(s):  
Rebeca Marcos ◽  
Ruy Alberto Caetano Corrêa Filho ◽  
Janessa Sampaio de Abreu ◽  
Guilherme Do Nascimento Seraphim ◽  
Ana Carla Carvalho Silva ◽  
...  
Keyword(s):  
Growth Curve ◽  
Growth Curves ◽  
Growth Patterns ◽  
Production Performance ◽  
Environment Interaction ◽  
Morphometric Traits ◽  
Mato Grosso ◽  
Colossoma Macropomum ◽  
Genotype Environment Interaction ◽  
The Family

The objective of this study was to obtain the growth curve of selectively bred tambaqui (Colossoma macropomum) reared in different environments. The experiment was carried out in the municipalities of Santo Antônio de Leverger (Mato Grosso – MT) and Campo Grande (Mato Grosso do Sul – MS), Brazil, over 431 days. Weight and morphometric traits of two families (A and B) from the second generation of selective breeding (G2) were measured every 30-45 days. The Gompertz regression model was used to obtain the growth curves. The production performance of both families and the interaction between families and locations (genotype × environment) were evaluated by analysis of variance considering the family (A and B), location (MT and MS), family × location interaction and error as variation factors. The asymptotic value (parameter A) obtained for weight and morphometric traits (except head length) was higher (P<0.05) in MT (weight of families A and B: 2279.6 g) than in MS (weight of family A: 1400.0 g; weight of family B: 1600.0 g). Family B showed better production performance in MS. There was a genotype × environment interaction effect on weight, body length and standard length. The two families have distinct growth patterns in different production environments. Family B has better growth performance in the environment with lower temperatures (MS).

A Parsimonious Number of Growth Curves

1993 ◽  
Vol 10 (3) ◽  
pp. 132-136 ◽  
Author(s):  
Boris Zeide
Keyword(s):  
Growth Pattern ◽  
Ecological Factors ◽  
Growth Curves ◽  
Site Index ◽  
Growth Conditions ◽  
Growth Patterns ◽  
Construction Methods ◽  
Complex Interactions ◽  
Site Index Curve ◽  
Index Curve

Abstract Construction of new site index curves is often justified by a lack of growth information for a given species and site. This justification presumes that there is a one-to-one correspondence between growth pattern and stand conditions which are determined by numerous genetic and ecological factors together with their complex interactions. Because these factors are combined in an infinite number of ways, each stand is unique and needs its own site index curve. The effort required for collecting growth information would be prohibitive. This effort is also unnecessary because many existing curves coincide with each other and are, therefore, redundant. Differences in species, site, and construction methods do not prevent the appearance of the same growth patterns. These facts indicate that unique growth conditions do not mean that each stand has a unique growth pattern. Therefore, a more productive approach to growth modeling consists of distilling these patterns from existing curves and yield tables rather than piling up more new site index curves. Earlier investigations showed that the diversity in growth curves can be reduced to a small number (15-30) of growth types. The present study demonstrates that the number of types can be further reduced to 3-5 without sacrificing accuracy of growth predictions. North. J. Appl. For. 10(3):132-136.

Sign in / Sign up

Export Citation Format

Share Document