scholarly journals the Haemolymph as a Storage Site for Cuticular ions During Premoult in the Freshwater/Land Crab Holthuisana Transversa

1984 ◽  
Vol 113 (1) ◽  
pp. 43-54
Author(s):  
STEPHEN SPARKES ◽  
PETER GREENAWAY

Holthuisana transversa (von Martens) utilizes the haemolymph as a storage site for ions reabsorbed from the cuticle in premoult. 66 % of the total body calcium, magnesium and phosphate from the preceding intermoult stage was stored in the haemolymph in premoult. Almost all of the calcium and phosphate and 73 % of the magnesium in the haemolymph was located in microspherules of average diameter 0.25 μm. The concentration of total calcium in the haemolymph in premoult was 150 times the normal intermoult value (13.2mmoll−1) but the activity of calcium in the haemolymph decreased from an intermoult value of 4.52mmoll−1 to 3.37 mmoll−1 in premoult. Postmoult crabs absorbed calcium from the water at a high rate and showed a high affinity for calcium ions; Km = 0.105±0.013 mmoll−1Ca.

2021 ◽  
Vol 16 (7) ◽  
pp. 487-494
Author(s):  
S.L. Niankovskyy ◽  
A.I. Pyshnyk ◽  
O.V. Kuksenko ◽  
O.I. Hrushka

Background. An integral part of a child’s physical and mental development is a balanced diet. Insufficient or inadequate for a child developing organism’s needs nutrition in preschool age leads to a delay in physical, cognitive, and mental development. The study was aimed to assess the macro-and micronutrient provision status of preschool children with psychomotor developmental delay, identify the presence of macro- and micronutrient deficiencies, define the connection between macro- and micronutrient levels in patient’s serum and psychomotor developmental disorders. Materials and methods. The study analyzed the results of biochemical blood tests of blood serum samples for total calcium, magnesium, and iron level in 30 preschool children with psychomotor developmental disorders. Results. Mental retardation was observed in 53.33 % of examined children, autism spectrum disorders — in 20 % of exami­ned children; minimal brain dysfunction — in 13.33 %, attention deficit hyperactivity disorder (ADHD) — in 13.33 %. 93.33 % of exami­ned children had a deficiency of total calcium, magnesium — in 63.33 %, iron — in 20 %. Ten percent of patients had a deficiency of both total calcium, magnesium, and iron; one child (3.33 %) had no deficits. The most common deficiency in almost all subgroups of examined children was a combined deficiency of total calcium and magnesium. Only in the minimal brain dysfunction subgroup, in 50 % of cases, there was a combined deficiency of total calcium and magnesium, and in other 50 % of cases — an isolated deficiency of total calcium. This study identified a reliable inverse correlation of moderate strength between the level of total calcium and psychomotor development disorders and between the level of magnesium and the hyperexcitability syndrome. This study detected a weak unreliable correlation between the levels of magnesium and neurological disorders; an inverse unreliable weak correlation was found between iron and psychomotor developmental disorders. Conclusions. The most common deficiency in almost all subgroups of examined children was a combined deficiency of total calcium and magnesium. This study identified a reliable inverse correlation of moderate strength between the level of total calcium and psychomotor developmental disorders and between the level of magnesium and the hyperexcitability syndrome. There is also a weak direct unreliable correlation between magnesium level and psychomotor disorders. An inverse unreliable weak correlation was detected between the concentration of iron and psychomotor disorders.


2019 ◽  
Vol 60 (4) ◽  
pp. 442-450 ◽  
Author(s):  
Yu Zhao ◽  
Junling Zhang ◽  
Xiaodan Han ◽  
Saijun Fan

Abstract Radiation can induce senescence in many organs and tissues; however, it is still unclear how radiation stimulates senescence in mouse small intestine. In this study, we use the bone marrow transplantation mouse model to explore the late effects of total body irradiation on small intestine. Our results showed that almost all of the body hairs of the irradiated mice were white (which is an indication of aging) 10 months after the exposure to radiation. Furthermore, compared with the age-matched control mice, there were more SA-β-galactosidase (SA-β-gal)–positive cells and an upregulation of p16 and p21 in 8 Gy–irradiated mice intestinal crypts, indicating that radiation induced senescence in the small intestine. Intestinal bacterial flora profile analysis showed that the diversity of the intestinal bacterial flora decreased in irradiated mice; in addition it showed that the principal components of the irradiated and control mice differed: there was increased abundance of Bacteroidia and a decreased abundance of Clostridia in irradiated mice. To explore the underlying mechanism, an RNA-sequence was executed; the results suggested that pancreatic secretion, and the digestion and absorption of proteins, carbohydrates, fats and vitamins were damaged in irradiated mice, which may be responsible for the body weight loss observed in irradiated mice. In summary, our study suggested that total body irradiation may induce senescence in the small intestine and damage the health status of the irradiated mice.


1983 ◽  
Vol 55 (1) ◽  
pp. 201-204 ◽  
Author(s):  
A. D. LeBlanc ◽  
H. J. Evans ◽  
P. C. Johnson ◽  
S. Jhingran

The purpose of this study was to evaluate the effect of deconditioning on the total body calcium in rats. Two separate experiments were performed using female Sprague-Dawley rats, 187-266 days of age. Total body calcium was measured in experimental and control rats during and following several weeks of voluntary exercise. The slope from the least-squares fit of total body calcium with time was used to obtain an average calcium balance for each animal during each study period. In both groups the exercised rats had a significantly decreased calcium balance after cessation of exercise, whereas no significant change was seen in nonexercised controls. In both groups, the exercised animals gained calcium at a significantly greater rate than controls. Our findings indicate that while exercised rats may gain calcium at a faster rate compared with nonexercising controls, the rate of gain following cessation of exercise is less than the controls.


2017 ◽  
Vol 5 (2) ◽  
pp. 2061-2066 ◽  
Author(s):  
MohannedAbdallaElhassan Sidahmed ◽  
◽  
NuhaEljaili Abubaker ◽  
GhadaA Elfadil ◽  
◽  
...  

2021 ◽  
Author(s):  
Suzana S. Jovanović-Šanta ◽  
◽  
Esma Isenović ◽  
Julijana A. Petrović ◽  
Yaraslau U. Dzichenka

About 75% of breast cancers express estrogen receptors (ERs), which is a good base for an efficient endocrine therapy. This gives the opportunity for the treatment of patients with antiestrogens, compounds that bind to the ERs and thus compete to estradiol (E2), preventing its action in progression of estrogen-depending cancers. Here we present results of testing the effect of the modified steroids, namely 17-substituted 16-nitrile 16,17-secoestrane compounds on the E2-ER complex forming, its stability, nuclear translocation and binding to DNA. Almost all compounds in moderate to high rate induced lower forming of this complex, destabilizing it – they increased Kd of this complex and decreased number of binding sites. Complex formed in the presence of some test secosteroids could pass to the nucleus, while other compounds inhibited translocation. In the presence of some compounds binding of the formed complex E2-ER to DNA was noticed. Docking followed molecular dynamics simulation was performed to reveal binding mode of E2 to ER in the presence of test secosteroids. Amino acids important for binding process and complex stabilization were detected. Analysis of the simulation data allowed identifying key amino acids and type of binding of the secoestrane compounds, important for high affinity binding of the steroidal compounds.


Author(s):  
Gabriel B. Iwasokun

The corona virus disease, otherwise known as COVID-19, is an extremely communicable and pathogenic viral infection caused by severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), which emerged in Wuhan, China in December 2019 and has spread to almost all the countries in the world. The transmission of the virus is through touching of the nose, eyes, or mouth by a finger that has been contaminated through droplets on a surface when a carrier sneezes or coughs. Since the existing fingerprint devices are predominantly contact based, it implies that they can aid in the transmission of the virus. This paper discusses the application of fingerprint devices in notable places with high rate of COVID-19 infection as well as the threats to fingerprint technologies and the countermeasures. The need to change focus and orientation towards contactless biometric technologies as sure solution to the fear and animosity expressed towards contact-based fingerprint technology is also expatiated.


1983 ◽  
Vol 244 (3) ◽  
pp. R327-R331 ◽  
Author(s):  
C. E. Cann ◽  
R. R. Adachi

Bone resorption was measured directly in flight and synchronous control rats during COSMOS 1129. Continuous tracer administration techniques were used, with replacement of dietary calcium with isotopically enriched 40Ca and measurement by neutron activation analysis of the 48Ca released by the skeleton. There is no large change in bone resorption in rats at the end of 20 days of spaceflight as has been found for bone formation. Based on the time course of changes, the measured 20–25% decrease in resorption is probably secondary to a decrease in total body calcium turnover. The excretion of sodium, potassium, and zinc all increase during flight, sodium and potassium to a level four to five times control values.


2012 ◽  
Vol 4 (1) ◽  
pp. 7-19 ◽  
Author(s):  
Sonia Savelli ◽  
Susan Joslyn

Abstract Recreational boaters in the Pacific Northwest understand that there is uncertainty inherent in deterministic forecasts as well as some of the factors that increase uncertainty. This was determined in an online survey of 166 boaters in the Puget Sound area. Understanding was probed using questions that asked respondents what they expected to observe when given a deterministic forecast with a specified lead time, for a particular weather parameter, during a particular time of year. It was also probed by asking respondents to estimate the number of observations, out of 100 or out of 10, that they expected to fall within specified ranges around the deterministic forecast. Almost all respondents anticipated some uncertainty in the deterministic forecast as well as specific biases, most of which were born out by an analysis of local National Weather Service verification data. Interestingly, uncertainty and biases were anticipated for categorical forecasts indicating a range of values as well, suggesting that specifying numeric uncertainty would improve understanding. Furthermore, respondents’ answers suggested that they expected a high rate of false alarms among warning and advisory forecasts. Nonetheless, boaters indicated that they would take precautionary action in response to such warnings, in proportions related to the size of boat they were operating. This suggests that uncertainty forecasts would be useful to these experienced forecast consumers, allowing them to adapt the forecast to their specific boating situation with greater confidence.


1987 ◽  
Vol 64 (4) ◽  
pp. 681-685 ◽  
Author(s):  
SEIICHI YASUMURA ◽  
JOHN F. ALOIA ◽  
CAREN M. GUNDBERG ◽  
JAMES YEH ◽  
ASHOK N. VASWANI ◽  
...  

1996 ◽  
Vol 17 (2) ◽  
pp. 159-164 ◽  
Author(s):  
J Tucci ◽  
V Hammond ◽  
P V Senior ◽  
A Gibson ◽  
F Beck

ABSTRACT During pregnancy, a placental calcium pump maintains the fetus in a hypercalcaemic state relative to the mother, a condition which has been thought to facilitate normal development of the fetal skeleton. Based on experiments performed in the sheep, parathyroid hormone-related protein (PTHrP) has been implicated as the hormone responsible for maintaining the placental calcium pump. In the present study on mice in which the PTHrP gene has been ablated by homologous recombination, we have measured both fetal and maternal circulating total and ionised calcium levels, as well as fetal total body calcium, in order to determine whether absence of PTHrP during fetal development has an effect on fetal calcium levels. Our results show that, in fetuses lacking PTHrP, circulating ionised calcium levels are significantly lower than those of heterozygote and wild-type littermates, but circulating total calcium levels show no difference. Total body calcium levels of null mutants are significantly higher than those of normal littermates. The role of PTHrP in maintaining the integrity of the transplacental calcium pump in the rodent thus remains unclear. It may be that the lower levels of fetal blood ionised calcium in mutant animals are due to disruption of the placental pump, but, if this is the case, compensatory mechanisms have operated to allow the excessive calcium deposition seen in the skeletons of these animals. Alternatively, the increased avidity of the bones for calcium may in itself have produced a lower equilibrium level of available ionised calcium.


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