Effect of hormone treatments on alarm substance cell counts in the pearl dace, Semotilus margarita

1986 ◽  
Vol 64 (2) ◽  
pp. 291-295 ◽  
Author(s):  
Jeaniene D. Smith ◽  
R. J. F. Smith
Keyword(s):  
Pimephales Promelas ◽  
Mucous Cell ◽  
Cell Loss ◽  
Alarm Substance ◽  
Androgen Treatment ◽  
Cell Counts ◽  
Sexual Characteristics ◽  
Alarm Substance Cells ◽  
The Difference ◽  
Induced Changes

The seasonal loss of alarm substance cells that normally occurs in breeding male and female pearl dace, Semotilus margarita, could not be induced by treatment with androgen, estrogen, salmon gonadotropin, or prolactin. Treatment with carp pituitary did lead to a significant reduction in alarm substance cell numbers. Androgen treatment induced changes in tuberculation and mucous cell counts. Salmon gonadotropin and carp pituitary increased breeding colouration. Prolactin treatment increased mucous cell counts. The lack of response of pearl dace alarm substance cells to androgen contrasts with the situation in fathead minnows, Pimephales promelas, where seasonal alarm substance cell loss is under androgen control. The difference may reflect differences in the annual cycle of secondary sexual characteristics.

Seasonal changes in the histology of the gonads and dorsal skin of the fathead minnow, Pimephales promelas

1978 ◽  
Vol 56 (10) ◽  
pp. 2103-2109 ◽  
Author(s):  
R. J. F. Smith
Keyword(s):  
Seasonal Changes ◽  
Pimephales Promelas ◽  
Mucous Cell ◽  
Cell Number ◽  
Alarm Substance ◽  
Breeding Period ◽  
Dorsal Skin ◽  
Nonbreeding Season ◽  
Alarm Substance Cells ◽  
Dermal Connective Tissue

In central Saskatchewan gonad weights of male and female fathead minnows reach peak values between June 1 and July 31. The precise timing of the peak seems to be determined by local weather (temperature). Gonad histology shows a predominance of early gametogenic stages during winter with gametogene sis being completed in the spring. The histology of the dorsal skin is similar in both sexes during the nonbreeding season but males develop a dorsal pad during the breeding season. Pad development involves seasonal changes in epidermal thickness, mucous cell number, and dermal connective tissue thickness. Males also lose their alarm substance cells briefly during the peak breeding period.

Male fathead minnows (Pimephales promelas Rafinesque) retain their fright reaction to alarm substance during the breeding season

1976 ◽  
Vol 54 (12) ◽  
pp. 2230-2231 ◽  
Author(s):  
R. J. F. Smith
Keyword(s):  
Breeding Season ◽  
Pimephales Promelas ◽  
Field Tests ◽  
Alarm Substance ◽  
Skin Extract ◽  
Fathead Minnows ◽  
Fright Reaction ◽  
Alarm Substance Cells

In laboratory and field tests, breeding male fathead minnows respond to conspecific skin extract with a fright reaction despite their own seasonal loss of alarm substance cells. Their fright reaction is facilitated by the presence of other fatheads.

Reduced alarm substance cell counts in male and androgen-treated zebra danios (Brachydanio rerio)

1986 ◽  
Vol 64 (2) ◽  
pp. 551-553 ◽  
Author(s):  
R. J. F. Smith
Keyword(s):  
Breeding Season ◽  
Reproductive Cycle ◽  
Epidermal Cells ◽  
Alarm Substance ◽  
Brachydanio Rerio ◽  
Cell Counts ◽  
Alarm Substance Cells

Ostariophysan fish possess large epidermal cells that contain the alarm substance or Schreckstoff characteristic of this group. In some species these alarm substance cells are retained throughout the reproductive cycle; in others they are completely absent from the epidermis during the breeding season in males only or in both sexes. Zebra danios represent a fourth category: males have fewer alarm-substance cells than do females and treatment with 17α-methyltestosterone leads to a further reduction, but not complete absence, of alarm substance cells. Treating females with 17α-methyltestosterone reduced the number of alarm substance cells in their epidermis.

A quantitative evaluation of some factors affecting the non-fatty solids of cow's milk

1960 ◽  
Vol 27 (1) ◽  
pp. 19-32 ◽  
Author(s):  
W. H. Alexander ◽  
F. B. Leech
Keyword(s):  
Cell Count ◽  
Residual Effect ◽  
Clinical Mastitis ◽  
High Cell ◽  
Factors Affecting ◽  
Stage Of Lactation ◽  
Cell Counts ◽  
Satisfactory Analysis ◽  
The Difference ◽  
Image Position

SummaryTen farms in the county of Durham took part in a field study of the effects of feeding and of udder disease on the level of non-fatty solids (s.n.f.) in milk. Statistical analysis of the resulting data showed that age, pregnancy, season of the year, and total cell count affected the percentage of s.n.f. and that these effects were additive and independent of each other. No effect associated with nutritional changes could be demonstrated.The principal effects of the factors, each one freed from effects of other factors, were as follows:Herds in which s.n.f. had been consistently low over a period of years were compared with herds in which s.n.f. had been satisfactory. Analysis of the data showed that about 70% of the difference in s.n.f. between these groups could be accounted for by differences in age of cow, stage of lactation, cell count and breed.There was some evidence of a residual effect following clinical mastitis that could not be accounted for by residual high cell counts.The within-cow regression of s.n.f. on log cell count calculated from the Durham data and from van Rensburg's data was on both occasions negative.The implications of these findings are discussed, particularly in relation to advisory work.

scholarly journals Cell Loss from the Nucleus Basalis of Meynert in Alzheimer's Disease

1986 ◽  
Vol 13 (S4) ◽  
pp. 435-440 ◽  
Author(s):  
R. Doucette ◽  
M. Fisman ◽  
V.C. Hachinski ◽  
H. Mersky
Keyword(s):  
Paraffin Section ◽  
Neuronal Loss ◽  
Cell Loss ◽  
Nucleus Basalis ◽  
Nucleus Basalis Of Meynert ◽  
Cell Counts ◽  
Group 3 ◽  
Group 2 ◽  
Death Group ◽  
Group 1

Abstract:We examined the degree of neuronal loss from the nucleus basalis of Meynert (nbM) in two groups of Alzheimer patients differing in the degree of intellectual impairment. Significant cell loss from the nbM was found only in the more severely demented group of patients. Mean cell counts (per lOu, paraffin section) were compiled separately for the anterior, intermediate and posterior subdivisions of the human nbM in three groups of subjects: Group 1 (N = 4) was severely demented and was untestable on the Extended Scale for Dementia (ESD) for at least the last two years of life; Group 2 (N = 4) was less demented and had completed at least one ESD test within 12 months of death; Group 3 (five controls) had died of non-neurological causes. In Group 2 there was a small (but insignificant) trend toward cell loss in the anterior subdivision, and a normal complement of neurons in both the intermediate and posterior subdivisions. There was, however, significant cell loss from all subdivisions of Group 1. How these cell counts may relate to the severity of the dementia is discussed.

THE FRIGHT REACTION IN NORTH AMERICAN FISH

1963 ◽  
Vol 41 (1) ◽  
pp. 69-77 ◽  
Author(s):  
Wolfgang Pfeiffer
Keyword(s):  
North American ◽  
Alarm Substance ◽  
Fish Skin ◽  
Cyprinid Species ◽  
Fright Reaction ◽  
Skin Physiology ◽  
Alarm Substance Cells

The fright reaction was found in five species of North American Cyprinidae including the predaceous northern squawfish, and in two species of Catostomidae. The threshold for Cyprinidae is 1/1000 N ("normal") extract or lower, that for Catostomidae at least a 1/100 N extract. The cyprinid species reacted very strongly to extract from other Cyprinidae but less strongly to catostomid extract; catostomid species reacted strongly to extract from other Catostomidae but less strongly to cyprinid extract. Salmon extract did not produce any reaction in Cyprinidae or Catostomidae. The epidermis of all species studied contained alarm substance cells; the epidermis of the Catostomidæ was very similar to that of the Cyprinidae. There was a relationship between number and size of the alarm substance cells (histology) and the quantity of alarm substance in the fish skin (physiology). The ability to respond to the alarm substance first appeared in young redside shiners at an age of 42 days, in young zebrafish at an age of 32 days, when the fish were kept at 26 °C.

Experimental Investigation of Effects of Extrusion Pressure on Cell Growth of Bioprinted Algae Cells in Green Bioprinting

2020 ◽  
Author(s):  
Laura Jerpseth ◽  
Ketan Thakare ◽  
Zhijian Pei ◽  
Hongmin Qin
Keyword(s):  
Cell Growth ◽  
Cell Count ◽  
Plant Cells ◽  
Extrusion Pressure ◽  
Layer By Layer ◽  
Animal Cells ◽  
Physical Damage ◽  
The Third ◽  
Cell Counts ◽  
The Difference

Abstract In bioprinting, biomaterials are deposited layer-by-layer to fabricate structures. Bioprinting has many potential applications in drug screening, tissue engineering, and regenerative medicine. Both animal cells and plant cells can be used to synthesize bioinks. Green bioprinting uses bioinks that have been synthesized using plant cells. Constructs fabricated via green bioprinting contain immobilized plant cells, with these cells arranged at desired locations. The constructs provide scaffolds for cell growth. Printing parameters affecting the growth of cells in green bioprinted constructs include print speed, needle diameter, extrusion temperature, and extrusion pressure. This paper reports a study to examine effects of extrusion pressure on cell growth (measured by cell count) in bioprinted constructs, using bioink containing Chlamydomonas reinhardtii algae cells. Three levels of extrusion pressure were used: 3, 5, and 7 bar. Cell counts in the bioprinted constructs were measured on the third and sixth days after bioprinting. It was found that, as extrusion pressure increased, cell count decreased on both the third and sixth days after bioprinting. Furthermore, the difference in cell counts between the third and the sixth days decreased as extrusion pressure increased. These trends suggest that increasing extrusion pressure during green bioprinting negatively affects cell growth. A possible reason for these trends is physical damage to or death of cells in the bioprinted constructs when extrusion pressure became higher.

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