THE INFLUENCE OF THE LITTER SIZE ON THE POST NATAL GROWTH OF THE ISLETS OF LANGERHANS IN THE RAT

1960 ◽  
Vol XXXV (IV) ◽  
pp. 533-540 ◽  
Author(s):  
Birger Petersson ◽  
Claes Hellerström ◽  
Bo Hellman
Keyword(s):  
Cell Number ◽  
Lower Number ◽  
The Body ◽  
The Other ◽  
Number Ratio ◽  
Significant Difference ◽  
Islet Volume ◽  
Islet Tissue ◽  
A Cell ◽  
Old Rats

ABSTRACT In a comparison of three week old rats from small and large litters it was observed that the total islet volume was more than three times as large in the former group. If on the other hand the total islet volume was expressed in relation to the body or the pancreatic weight, no significant difference was found between the animals in the small and large litters. The smaller absolute islet volume in the group 'large litters' was primarily due to a lower number of A cells, i. e. the B/A cell number ratio was significantly higher than in the group 'small litters'. The size of the litters, which normally shows considerable variations, thus greatly influences not only the body growth of the rats but also the post natal development of the islet tissue.

EFFECTS OF LONG TERM ADMINISTRATION OF GLUCAGON ON THE PANCREATIC ISLET TISSUE OF RATS AND GUINEA-PIGS

1963 ◽  
Vol 44 (1) ◽  
pp. 139-149 ◽  
Author(s):  
Birger Petersson ◽  
Bo Hellman
Keyword(s):  
Guinea Pigs ◽  
Cell Number ◽  
Dark Field ◽  
The Body ◽  
Initial Increase ◽  
Adult Age ◽  
Number Ratio ◽  
Islet Volume ◽  
Term Administration

ABSTRACT Rats and guinea-pigs were injected every eight hours with crystalline glucagon (0.3–0.6 mg/kg) and killed after different periods of treatment up to 30 days. Immature animals (glucagon treatment commenced on the second postnatal day) were also included among the rats investigated. While the immature glucagon treated rats grew almost as well as their litter mate controls, there was a marked reduction of the body and adrenal weights, when the injections were started at a more adult age. In the latter rats the total islet volume was significantly reduced and the A1/A2 cell number ratio increased from 0.24 ± 0.02 to 0.32 ± 0.02. In the guinea-pigs the glucagon treatment resulted in a considerable decrease in both the body and pancreatic weights. These changes were associated with a significant increase in the relative amount of the endocrine pancreas, the total islet volume being unchanged. While the A1 cells appeared unaffected by the glucagon treatment, the A2 cells were markedly atrophied. After an apparent initial increase there was a subsequent progressive diminution of the silvery-white dark field granulation of the A2 cells during the glucagon treatment. The postcoupled benzylidene reaction for tryptophane also decreased and became insignificant in guineapigs injected with glucagon for a long period. In the latter animals the percentage of A2 cells was only 3.4 ± 0.2 as compared with 24.4 ± 1.3 for the controls. As a consequence of this, the A1/A2 cell number ratio was about 6 times as high in the glucagon treated guinea-pigs. The data obtained for the longer term adaptation of the islets of Langerhans to the administration of glucagon support the concept that this hormone is secreted by the silver-negative A2 cells.

Increase in Cell Number as a Factor in the Growth of the Organs and Tissues of the Young Male Rat

Development ◽  
1962 ◽  
Vol 10 (4) ◽  
pp. 530-562
Author(s):  
M. Enesco ◽  
C. P. Leblond
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Room Temperature ◽  
Young Male ◽  
Cell Number ◽  
The Body ◽  
Male Rat ◽  
The Past ◽  
Old Rats ◽  
Young Rat

While the organs and tissues of the young rat are known to increase in size with age (Donaldson, 1924), little is known of the role played by the component cells in this increase. There is evidence that cells enlarge (Levi, 1906; Plenk, 1911) and new cells are added (Strasburger, 1893), but we do not know to what extent the enlargement and proliferation of the cells cause the growth of organs and tissues. The present work is an attempt to clarify this problem. In the past, the growth of organs and tissues has often been measured by weight gain (Donaldson, 1924). However, this approach might be misleading, since the body-weight may increase in the absence of growth, for instance as a result of fat-storage in old rats, of pregnancy in females, and even of changes in room temperature.

DISTRIBUTION OF THE TWO TYPES OF A CELLS IN THE PANCREATIC ISLETS OF SOME MAMMALIAN SPECIES

1964 ◽  
Vol 46 (2) ◽  
pp. 307-316 ◽  
Author(s):  
Gunnar Alm ◽  
Bo Hellman
Keyword(s):  
Guinea Pig ◽  
Pancreatic Islets ◽  
Considerable Increase ◽  
Mammalian Species ◽  
Cell Number ◽  
The Other ◽  
Rat Pancreas ◽  
Number Ratio ◽  
A Cells

ABSTRACT Both types of pancreatic A cells were identified in the sheep, hamster, guinea pig, rat, pig and monkey. The argyrophil A1 cells displayed a distinct metachromatic reaction in the latter two mammals. While neither the A1 nor the A2 cells were localized to any particular islet region in the guinea pig and monkey, characteristic islet positions were noted in each of the other four species. There was a considerable increase of the A2/A1 cell number ratio with increasing islet diameter. The increased proportion of the A2 cells in the large islets was especially marked in the rat. While no differences were encountered between the duodenal and splenic pancreatic regions for the relative contributions of the A1 and A2 cells in the islets of the pig, monkey and guinea pig, the analyses of the rat pancreas revealed a higher frequency of A1 cells in the splenic part.

scholarly journals Relationship between body weight and leptin concentrations in mink dams and the birth parameters of kits

2016 ◽  
Vol 72 (12) ◽  
pp. 755-759 ◽  
Author(s):  
Monika Bryl ◽  
Hanna Bis-Wencel ◽  
Brygida Ślaska ◽  
Bożena Nowakowicz-Dębek ◽  
Zbigniew Bełkot ◽  
...  
Keyword(s):  
Body Weight ◽  
Body Condition ◽  
Scoring System ◽  
The Body ◽  
The Other ◽  
Blood Samples ◽  
Serum Leptin ◽  
Significant Difference ◽  
Analysis Of Results ◽  
The Impact

The aim of this study was to assess the impact of the leptin concentration and body weight of mink females on the birth parameters of their kits. Blood samples were collected 3 times during preparation for reproduction, 7±2 days before mating. Total leptin concentration in serum was measured using commercial RIA kits (Millipore, St. Charles, Missouri USA). Research was conducted on 20 clinically healthy scanbrown female minks (Neovison Vison) aged 2-3 years. To evaluate their body condition, the females were divided into two groups based on the BCS scoring system. In the first group, referred to as BCS 2, lean females were included, and the second group (BCS 4) consisted of obese females. In mink dams belonging to BCS 2, the average leptin values were one-fourth of those in the BCS 4 group. The results obtained indicate the influence of the body mass of minks during preparation for reproduction on serum leptin concentration. The results of the Mann-Whitney U test showed a statistically significant difference between weights and leptin concentrations in groups BCS 2 and BCS 4. Among the other traits, such differences were not found. The analysis of results obtained in the two mink groups did not reveal a clear relationship between leptin in the serum of mothers before mating and the birth parameters of their kits.

Stress Reactions Resulting from the Relocation of an aged Population

1968 ◽  
Vol 13 (3) ◽  
pp. 201-209 ◽  
Author(s):  
V. A. Kral ◽  
B. Grad ◽  
J. Berenson
Keyword(s):  
Respiratory Infections ◽  
Normal Subjects ◽  
Lower Number ◽  
The Body ◽  
Stress Reactions ◽  
Men And Women ◽  
Relative Percentage ◽  
Significant Difference ◽  
Normal Women ◽  
Normal Men

Fifty-four subjects from 64 to 94 years of age were investigated for their stress reactions following their relocation from one site to another. Forty of them, 16 men and 24 women, were psychiatrically normal, while the remainder (eight men and six women) were suffering from a psychosis, which in all cases, except one, was of organic type. There was no statistically significant difference between the ages of the men and women, and of the normals and psychotics. The same was true in the case of the body weight, except that the men weighed more than the women. Plasma corticoid (PC) levels were determined two to nine days before relocation and eight to 17 days afterwards. One-third of the subjects made no complaints in regard to their health within four months of relocation (NC 33%), while the rest either reported symptoms for which there did not appear to be any apparent organic cause (WS 43%) or presented organic signs (OS 24%). Most of the complaints in the WS category were related to the abdomen, while most of those in the OS group were either due to respiratory infections or cardiovascular conditions. The relative percentage of persons falling into these three categories was essentially similar in normal men and in normal women and in psychotic men and psychotic women. However, the psychotics had a significantly higher incidence of OS persons and a significantly lower number of NC subjects than did the normals, while the incidence of WS was essentially the same in these two groups. Following relocation the PC levels increased in normal men, but decreased in normal women. Furthermore, a greater PC increase was observed in men of the OS group than in those of the WS category, who in turn showed a greater increase than the NC males. This was not observed in the women. Men in each of the NC, WS and OS categories had higher PC levels than women of the same category, and psychotics higher than normals. Twenty-five per cent of the normal men died within the first six months of relocation but none of the normal women, a statistically significant difference. Within 23 months of relocation reliably more psychotics died than normals. In conclusion, normal aged men appeared to suffer more from the relocation than normal aged women, and psychotic aged persons more than psychiatrically normal subjects of the same age.

scholarly journals Penggunaan Larutan Pepaya (Carica papaya) sebagai Larvasida Nyamuk Aedes aegypty

2019 ◽  
Vol 7 (2) ◽  
pp. 59
Author(s):  
Restu Prastiwi ◽  
Anita Dewi Moelyaningrum ◽  
Prehatin T. N
Keyword(s):  
Experimental Study ◽  
Aedes Aegypti ◽  
Carica Papaya ◽  
Larval Growth ◽  
Hemorrhagic Fever ◽  
The Body ◽  
The Other ◽  
Control Group ◽  
Significant Difference ◽  
The Impact

<p><em>Aedes aegypti mosquito is a type of mosquito that can carry dengue virus that causes dengue fever. This mosquito has the potential to transmit dengue hemorrhagic fever (DHF). DHF is a disease characterized by sudden fever, bleeding both on the skin and in other parts of the body and can cause shock and death. So in order to reduce the impact of the disease, there are several ways that must be taken. One way of controlling that is done to reduce the population of aedes aegypti mosquitoes is by reducing larval growth by using a solution of papaya leaves as larvacide. Papaya leaves contain tannins of 0.12%. So it is possible to kill larvae. The purpose of this study was to analyze the differences in the average mortality of untreated instar 1 aedes aegypti larvae and treated with a solution of distilled papaya leaves, amounting to 0ml / 100ml (X0), 1ml / 100ml (X1), 2ml / 100ml (2) , 4ml / 100m (X3) with observations every 6 hours for 24 hours. This study is a true experimental study with the presentation of the data analyzed using the kruskal wallis test on spss. The results showed that there were differences between the control group and the treatment group (p &lt;0.05). The most significant difference occurred in the 4ml / 100ml (X3) group which had the highest mortality than the other groups. So the higher the concentration and the longer the duration of exposure, the higher the mortality rate in the larvae. </em></p>

scholarly journals COMPARISON OF MUSCULOSKELETAL STRESS ON LUMBAR, SHOULDER, AND WRIST JOINTS WHILE MAKING A BED USING EASYTUCK PAD VERSUS OTHER BED-MAKING TOOLS

2020 ◽  
Author(s):  
ARMIA ABDO ◽  
HANI AL-NAKHLI
Keyword(s):  
Repeated Measures ◽  
Random Order ◽  
The Body ◽  
The Other ◽  
Time Range ◽  
Subjective Data ◽  
Risk Of Injury ◽  
Repeated Measures Analysis ◽  
Significant Difference ◽  
Queen Size

Objective: Currently, there are multiple bed-making tools utilized by consumers and businesses with the intention of increasing safety and reducing time to make a bed. In this study, we will compare musculoskeletal stress, time, and preference of making a bed using the EasyTuck pad versus three other bed-making tools and making a bed without any bed-making tool. Methods: A sample of ten subjects performed the task of making a queen size mattress bed with one bottom fitted sheet and one top flat sheet, using the EasyTuck pad versus three other bed-making tools, and making a bed without any bed-making tool, in a random order. Time to make the bed, forces on the low back, shoulders and wrist, and the number of times each individual bent forward were measured during each trial. In addition, subjective preferences were measured using a simple questionnaire. Results: Repeated measures analysis of variance was used to analyze the differences between the five different procedures. There were significant differences for all the measured variables. Regarding the time needed to make one bed, the EasyTuck pad had the least time range (80.6 s±4.3), which was approximately 40 s less than making the bed with no tool (p<0.001). Furthermore, for the overall lumbar spine impulse force, the EasyTuck pad had the largest overall reduction in this category (90.6%). Regarding the subjective data, the EasyTuck pad had an overall rating of 9.4 out of 10, compared to the other tools with ratings of 5.9, 5.1, and 3.4 out of 10, which was a statistically significant difference (p<0.001). Conclusion: Making beds on a regular basis poses risk of injury, especially for those who are required to perform this for their occupation. However, using assistive tools for bed-making, could minimize, and prevent injuries and overload to the lower back, and other parts of the body, making the bed-making task safer. Based on our findings, the EasyTuck pad was by far the most efficient and safest tool to assist in making beds, with the lowest possible risk of injury when compared to all the other tools tested.

Memoirs: Materials for a Monograph of the Ascons.--I. On the Origin and Growth of the Triradiate and Quadriradiate Spicules in the Family Clathrinidæ

1898 ◽  
Vol s2-40 (160) ◽  
pp. 469-587
Author(s):  
E. A. MINCHIN
Keyword(s):  
Distal Portion ◽  
The Body ◽  
The Other ◽  
Ground Substance ◽  
Connective Tissue Layer ◽  
Dermal Layer ◽  
Straight Line ◽  
The Family ◽  
A Cell ◽  
Pore Cell

1. The first appearance of a calcareous spicule or spicular element, both ancestrally and in the actual development, was probably a minute vacuole in a cell of the dermal layer, filled with an organic substance perhaps identical with the intercellular ground substance, within which the minute sclerite appeared as a crystal or concretion. 2. The ancestral sclerite, though crystalline in structure, soon assumed a non-crystalline form as a whole, as an adaptation to its secondarily acquired function of support, and as it grew in size the contents of the vacuole formed the spicule sheath. 3. The ancestral form of spicule in the Calcarea was a simple monaxon, placed tangentially and completely embedded in the body-wall, lying between two adjacent pores. 4. From this ancestral spicule the forms of spicule now occurring in the Calcarea arose as follows: (a) the primitive monaxon acquired a distal portion projecting from the surface, as in the existing primary monaxons; (b) groups consisting each of three primitive monaxons became united by their contiguous ends to form a single triradiate system; (c) to some of the triradiate systems thus formed a fourth ray was added, secreted by the pore-cell, giving rise to the quadriradiate system ; (d) some of the triradiate systems, by loss of one ray and placing of the other two in a straight line, or by loss of two rays, perhaps became modified into secondary monaxon spicules. 5. The power of secreting a monaxon sclerite was primitively possessed by every cell of the dermal layer, and this condition appears to be retained in Leucosolenia. In Clathrina, on the other hand, all the skeletogenous cells migrate inwards from the dermal epithelium, and form a connective-tissue layer distinct in function from the contractile, undifferentiated dermal epithelium. In Leucosolenia also the actinoblasts of the triradiate systems form a deeper layer, but the dermal epithelium secretes primary monaxons--at least in the young form--and is non-contractile. 6. The forms of the spicules are the result of adaptation to the requirements of the sponge as a whole, produced by the action of natural selection upon variation in every direction.

Visual Hemispheric Asymmetry and Right-Left Confusion

1987 ◽  
Vol 64 (3) ◽  
pp. 915-921 ◽  
Author(s):  
Dionisio Manga ◽  
Soledad Ballesteros
Keyword(s):  
Body Image ◽  
Hemispheric Asymmetry ◽  
Reaction Times ◽  
The Body ◽  
The Other ◽  
Perceptual Asymmetry ◽  
Significant Difference ◽  
Self Reports ◽  
Visual Hemifields ◽  
The Relationship

From 357 university students two groups of 8 women each were selected, one group with high right-left confusion and the other without such confusion according to self-reports. Reaction times to stimuli tachistoscopically presented in visual hemifields were recorded to estimate the relationship between perceptual asymmetry and right-left confusion. A significant difference between hemifields and an interaction of hemifield by group appeared, whereas asymmetry in the highly confused group was not so related. According to a model of cerebral functioning in the formation of the body image, these results suggest subjects with high right-left confusion have greater hemispheric bilateralization.

THE EFFECT OF AGEING ON THE NUMBER OF THE ISLETS OF LANGERHANS IN THE RAT

1959 ◽  
Vol XXXII (I) ◽  
pp. 78-91 ◽  
Author(s):  
Bo Hellman
Keyword(s):  
Body Weight ◽  
Age Groups ◽  
The Body ◽  
Male Rats ◽  
Quantitative Relation ◽  
List Type ◽  
Positive Correlation ◽  
Islet Volume ◽  
Old Rats ◽  
Lower Size

ABSTRACT Information concerning the so called 'total number' of islets is inexact. The number of islets should instead be expressed as that number which exceeds a well defined and easily identifiable lower size boundary. Studies on the numerical distribution of the islets show, in a comparison between two animals, that while the same lower size limit must be set in each case, considerable latitude may be exercised in selecting its actual value without disturbing the results. In this investigation only those islets, whose diameter was equal to or exceeded 46.9 μ were counted. The effect of ageing on the number of islets has been studied in a total of 75 male rats, which were nourished on a diet well defined calorically. The rats were killed on the 1st, 5th, 21st, 100th and 480th days of life. The following observations were made: With increase in age there was a marked increase in the number of islets. The value in the oldest animals was on the average more than 13 times that in the new-born. If the number of islets is expressed in relation to the total body weight or the weights of liver or pancreas, the ratio is markedly reduced with increasing age. The 480 days old rats were, however, an exception, as the values for this age showed a statistically significant increase as compared with 100 days old rats. When plotted in a double logarithmic co-ordinate system the liver and pancreatic weights were linear functions of the body weight in all the age groups studied. The corresponding regression between the islet number and the body weight was, however, curvilinear, so that the rate of increase was initially slow (between 0–5 days) but between the two oldest groups (100 and 480 days) it approached that of the pancreatic and liver weights. In each age group there is a strongly positive correlation between the number of islets and the total islet volume. In most of the age groups there was statistical support for a positive correlation between body weight and number of islets. Within the different age groups a quantitative relation between the number of islets and the weight of the pancreas was not apparent after the common positive correlation with the body weight had been eliminated by calculating the partial correlations. The regular mathematical arrangement of the islet tissue makes it possible to determine the actual number of islets by only counting the number of islet section surfaces which exceed a certain defined size.

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