The fate of calcium in the diet of Rhodnius prolixus: storage in concretion bodies in the Malpighian tubules

1991 ◽  
Vol 157 (1) ◽  
pp. 483-502 ◽  
Author(s):  
S. H. Maddrell ◽  
G. Whittembury ◽  
R. L. Mooney ◽  
J. B. Harrison ◽  
J. A. Overton ◽  
...  
Keyword(s):  
Calcium Concentration ◽  
Rhodnius Prolixus ◽  
The Body ◽  
Malpighian Tubules ◽  
Calcium Deposition ◽  
X Ray Diffraction ◽  
Calcium Deposits ◽  
Membrane Bound ◽  
High Concentrations

We have investigated the fate of the large amounts of calcium ingested by Rhodnius prolixus in its meals of blood. 45Ca2+ injected into the haemolymph or fed to fifth-stage Rhodnius reared on rabbits is accumulated at high concentrations in the cells of the upper Malpighian tubules; very little is excreted from the body This 45Ca2+ accumulation goes on continuously for at least 12 days and the rate of uptake is increased several-fold within 3–4 days of a meal. The extent of calcium accumulation in tubule cells is correlated with the presence of intracellular membrane-bound concretion bodies, which are therefore likely sites of calcium deposition. X-ray diffraction showed that the calcium deposits are non-crystalline. Tubules from rabbit-fed fifth-stage Rhodnius contain 410 mmol l-1 calcium; in those from chicken-fed insects the calcium concentration is over 1 mol l-1; and in those fed in vitro on heparinised low-K+ sheep blood the calcium concentration is only 21 mmol l-1. The concentration of calcium in the haemolymph in all these insects was 8 mmol l-1 and its activity determined by an ion-selective electrode was 2.5 mmol l-1. 45Ca2+ deposited in the tubules is readily exchangeable, but the efflux preferentially passes to the haemolymph side of the tubule epithelium. The ability to sequester calcium in the Malpighian tubules may prevent calcium from interfering with reabsorptive processes in the rectum.

scholarly journals Collagen-Based Electrospun Materials for Tissue Engineering: A Systematic Review

2021 ◽  
Vol 8 (3) ◽  
pp. 39
Author(s):  
Britani N. Blackstone ◽  
Summer C. Gallentine ◽  
Heather M. Powell
Keyword(s):  
Systematic Review ◽  
Tissue Engineering ◽  
Collagen Type I ◽  
The Body ◽  
Pool Data ◽  
Type I ◽  
High Concentrations ◽  
Increased Strength

Collagen is a key component of the extracellular matrix (ECM) in organs and tissues throughout the body and is used for many tissue engineering applications. Electrospinning of collagen can produce scaffolds in a wide variety of shapes, fiber diameters and porosities to match that of the native ECM. This systematic review aims to pool data from available manuscripts on electrospun collagen and tissue engineering to provide insight into the connection between source material, solvent, crosslinking method and functional outcomes. D-banding was most often observed in electrospun collagen formed using collagen type I isolated from calfskin, often isolated within the laboratory, with short solution solubilization times. All physical and chemical methods of crosslinking utilized imparted resistance to degradation and increased strength. Cytotoxicity was observed at high concentrations of crosslinking agents and when abbreviated rinsing protocols were utilized. Collagen and collagen-based scaffolds were capable of forming engineered tissues in vitro and in vivo with high similarity to the native structures.

scholarly journals Calcinosis cutis associated with systemic sclerosis: a rare case report

2020 ◽  
Vol 7 (8) ◽  
pp. 2803
Author(s):  
Surya Rao Rao Venkata Mahipathy ◽  
Alagar Raja Durairaj ◽  
Narayanamurthy Sundaramurthy ◽  
Anand Prasath Jayachandiran
Keyword(s):  
Systemic Sclerosis ◽  
The Body ◽  
Calcium Deposition ◽  
Pressure Sores ◽  
Connective Tissue Disorders ◽  
Calcinosis Cutis ◽  
Rare Case Report ◽  
The Face ◽  
Subcutaneous Tissues ◽  
Calcium Deposits

Calcinosis cutis is abnormal calcium deposition in the skin and subcutaneous tissues of the body. It is generally associated with autoimmune connective tissue disorders and in our case, it is systemic sclerosis. It most commonly occurs in the fingers presenting with pain and functional impairment. Here, we present a case of calcinosis cutis with systemic sclerosis in a teenage girl presented with bilateral gluteal pressure sores and multiple sites of calcium deposition like sacrum, upper limbs, knees and the face. We treated here with reconstructive surgery with Limberg flaps for the pressure ulcers with excision and primary closure of the other sites with calcium deposits. 

Effects of high calcium levels on the disturbed extrusion of the second polar body during in vitro fertilization in C3H/He mouse substrains

Zygote ◽  
2019 ◽  
Vol 28 (1) ◽  
pp. 83-85
Author(s):  
Y. Ohta-Takada ◽  
Y. Nagao ◽  
S. Kito
Keyword(s):  
Calcium Concentration ◽  
Inbred Mice ◽  
Polar Body ◽  
Efficient Production ◽  
Vitro Fertilization ◽  
Practical Applications ◽  
High Calcium ◽  
High Concentrations ◽  
Second Polar Body

SummaryWe previously reported that high concentrations (≥3.42 mM) of calcium during in vitro fertilization (IVF) disturbed the extrusion of the second polar body (PBII) in C3H/He inbred mice. In this study, the substrain specificity of this phenomenon was examined under 1.71–6.84 mM calcium concentration in ova from six C3H/He mouse commercially available substrains in Japan. PBII extrusion in ova from J substrains was not affected by calcium concentrations (<10% at any calcium level), but was grossly disturbed at high calcium levels in the ova of other substrains. This result has practical applications for the efficient production of normal zygotes by IVF, therefore contributing to the reduction in the numbers of donor animals for further zygote or embryo manipulation. Care must be taken in choosing IVF medium for particular strains and substrains.

scholarly journals Morphology andIn VitroBehavior of Electrospun Fibrous Poly(D,L-lactic acid) for Biomedical Applications

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Toshihiro Inami ◽  
Yasuhiro Tanimoto ◽  
Masayuki Ueda ◽  
Yo Shibata ◽  
Satoshi Hirayama ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Biomedical Applications ◽  
Polymer Concentration ◽  
The Body ◽  
Solution Flow Rate ◽  
Apatite Formation ◽  
X Ray Diffraction ◽  
Solution Flow

This work describes the fabrication, optimization, and characterization of electrospun fibrous poly(D,L-lactic acid) (PDLLA) for biomedical applications. The influences of the polymer concentration of the electrospinning solution (5, 10, or 15 wt%) and the solution flow rate (0.1, 0.5, 1.0, or 2.0 mL/h) on the morphology of the obtained fibrous PDLLA were evaluated. Thein vitrobiocompatibility of two types of PDLLA, ester terminated PDLLA (PDLLA-R) and carboxyl terminated PDLLA (PDLLA-COOH), was evaluated by monitoring apatite formation on samples immersed in Hanks’ balanced salt (HBS) solution. 15 wt% polymer solution was the most beneficial for preparing a fibrous PDLLA structure. Meanwhile, no differences in morphology were observed for PDLLA prepared at various flow rates. Apatite precipitate is formed on both types of PDLLA only 1 day after immersion in HBS solution. After 7 days of immersion, PDLLA-COOH showed greater apatite formation ability compared with that of PDLLA-R, as measured by thin-film X-ray diffraction. The results indicated that the carboxyl group is effective for apatite precipitation in the body environment.

Endogenous Ethanol ‘Auto-Brewery Syndrome’ as a Drunk-Driving Defence Challenge

2000 ◽  
Vol 40 (3) ◽  
pp. 206-215 ◽  
Author(s):  
B K Logan ◽  
A W Jones
Keyword(s):  
Venous Blood ◽  
Drunk Driving ◽  
Hepatic Metabolism ◽  
The Body ◽  
Endogenous Ethanol ◽  
Activity Of Enzymes ◽  
High Concentrations ◽  
Open Question ◽  
Reduced Activity

The concentration of ethanol in blood, breath or urine constitutes important evidence for prosecuting drunk drivers. For various reasons, the reliability of the results of forensic alcohol analysis are often challenged by the defence. One such argument for acquittal concerns the notion that alcohol could be produced naturally in the body, hence the term ‘auto-brewery’ syndrome. Although yeasts such as Candida albicans readily produce ethanol in-vitro, whether this happens to any measurable extent in healthy ambulatory subjects is an open question. Over the years, many determinations of endogenous ethanol have been made, and in a few rare instances (Japanese subjects with very serious yeast infections) an abnormally high ethanol concentration (<80 mg/dl) has been reported. In these atypical individuals, endogenous ethanol appeared to have been produced after they had eaten carbohydrate-rich foods. A particular genetic polymorphism resulting in reduced activity of enzymes involved in hepatic metabolism of ethanol and a negligible first-pass metabolism might explain ethnic differences in rates of endogenous ethanol production and clearance. Other reports of finding abnormally high concentrations of ethanol in body fluids from ostensibly healthy subjects suffer from deficiencies in study design and lack suitable control experiments or used non-specific analytical methods. With reliable gas chromatographic methods of analysis, the concentrations of endogenous ethanol in peripheral venous blood of healthy individuals, as well as those suffering from various metabolic disorders (diabetes, hepatitis, cirrhosis) ranged from 0–0.08 mg/dl. These concentrations are far too low to have any forensic or medical significance. The notion that a motorist's state of intoxication was caused by endogenously produced ethanol lacks merit.

In vitro effect of Canavalia ensiformis urease and the derived peptide Jaburetox-2Ec on Rhodnius prolixus Malpighian tubules

2009 ◽  
Vol 55 (3) ◽  
pp. 255-263 ◽  
Author(s):  
Fernanda Stanisçuaski ◽  
Victoria Te Brugge ◽  
Célia R. Carlini ◽  
Ian Orchard
Keyword(s):  
Rhodnius Prolixus ◽  
Malpighian Tubules ◽  
Canavalia Ensiformis ◽  
Vitro Effect

scholarly journals Melatonin’s neuroprotective role in mitochondria and its potential as a biomarker in aging, cognition and psychiatric disorders

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lindsay M. Melhuish Beaupre ◽  
Gregory M. Brown ◽  
Vanessa F. Gonçalves ◽  
James L. Kennedy
Keyword(s):  
Psychiatric Disorders ◽  
Free Radical Scavenger ◽  
The Body ◽  
Radical Scavenger ◽  
Pineal Melatonin ◽  
Mediated Effects ◽  
Ability To Act ◽  
High Concentrations ◽  
Mitochondrial Oxidative Metabolism

AbstractMelatonin is an ancient molecule that is evident in high concentrations in various tissues throughout the body. It can be separated into two pools; one of which is synthesized by the pineal and can be found in blood, and the second by various tissues and is present in these tissues. Pineal melatonin levels display a circadian rhythm while tissue melatonin does not. For decades now, melatonin has been implicated in promoting and maintaining sleep. More recently, evidence indicates that it also plays an important role in neuroprotection. The beginning of our review will summarize this literature. As an amphiphilic, pleiotropic indoleamine, melatonin has both direct actions and receptor-mediated effects. For example, melatonin has established effects as an antioxidant and free radical scavenger both in vitro and in animal models. This is also evident in melatonin’s prominent role in mitochondria, which is reviewed in the next section. Melatonin is synthesized in, taken up by, and concentrated in mitochondria, the powerhouse of the cell. Mitochondria are also the major source of reactive oxygen species as a byproduct of mitochondrial oxidative metabolism. The final section of our review summarizes melatonin’s potential role in aging and psychiatric disorders. Pineal and tissue melatonin levels both decline with age. Pineal melatonin declines in individuals suffering from psychiatric disorders. Melatonin’s ability to act as a neuroprotectant opens new avenues of exploration for the molecule as it may be a potential treatment for cases with neurodegenerative disease.

scholarly journals EXPERIMENTAL STUDIES ON INFLAMMATION

1923 ◽  
Vol 37 (4) ◽  
pp. 511-524 ◽  
Author(s):  
Elizabeth Pauline Wolf
Keyword(s):  
Inflammatory Reaction ◽  
White Blood Cells ◽  
Experimental Studies ◽  
The Body ◽  
Polymorphonuclear Leucocytes ◽  
Inflammatory Reactions ◽  
Croton Oil ◽  
High Concentrations

1. None of the salts tested produce a marked inflammation in vivo in concentrations under 10 per cent. Potassium salts and the different citrates produced atypical inflammatory reactions in mice, but not in frogs. There was no true inflammation, however, characterized by blood vessel changes, migration of polymorphonuclear leucocytes and erythrocytes, and fluid exudation. 2. Synergistic action occurs when equal parts of strontium and magnesium salts are employed. There is a change in the appearance of the mesentery without a true inflammation, and this change does not occur with either salt alone. 3. Amino-acids and amines as a class do not produce inflammation, but histamine produces a marked inflammatory reaction in frogs and mice. 4. Tyramine does not cause an inflammatory reaction but has other marked effects; agglutination thrombi occur within the smaller blood vessels, both veins and arteries; in frogs there is a rapid clumping of the white blood cells followed by a true coagulation with strands of fibrin and entanglement of erythrocytes. This is very widespread and often kills the animal within an hour after injection. In mice it is the erythrocytes that clump and coagulation occurs very much later, usually at the end of 24 hours; still later there is complete absorption of the coagulated masses and the mesenteric circulation returns to normal. None of the mice died during the stage of clumping, and the clots never extended up the larger vessels as they did in the frogs. These effects are similar to the phenomena observed in the in vitro work, in which clumping of the cells appeared constantly. 5. Cantharidinum, histamine, and turpentine produced the most rapid and marked inflammation of any substances tried. These substances are all strongly positively chemotactic in vitro. The differences occurring when these substances are used in different species is a quantitative rather than a qualitative one, the body temperature being of some importance. Papain acted only in warmblooded animals; this is consistent with its chemotactic action in vitro. The degree of positive chemotaxis varied markedly with the blood employed and in the in vivo work the inflammation varied with the species of animal used. 6. Certain substances produced inflammation only some time after injection; this is true of scarlet R and croton oil in weak dilutions. These are not strongly positively chemotactic. 7. Parazol produces an inflammation associated with necrosis of the tissues. This is similar to the results obtained in vitro, parazol being positively chemotactic in low concentrations and negative in high concentrations. 8. The exact chemical nature of many of the substances which produce marked inflammation is unknown. This is true of cantharidin, and the active constituents of turpentine and croton oil. 9. All substances which produce marked and rapid inflammation on injection are positively chemotactic, but not all strongly positively chemotactic substances produce inflammation; i.e., calcium compounds, sodium phosphate, etc. 10. Only substances which are positively chemotactic and also soluble in oil seem capable of producing inflammation in animals.

scholarly journals Effect of Trimetaphosphate and Fluoride Association on Hydroxyapatite Dissolution and Precipitation In Vitro

2014 ◽  
Vol 25 (6) ◽  
pp. 479-484 ◽  
Author(s):  
Alberto Carlos Botazzo Delbem ◽  
José Antonio Santos Souza ◽  
Ana Carolina Soares Fraga Zaze ◽  
Eliana Mitsue Takeshita ◽  
Kikue Takebayashi Sassaki ◽  
...  
Keyword(s):  
Calcium Fluoride ◽  
Calcium Concentration ◽  
Ph Value ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sodium Trimetaphosphate ◽  
Hydroxyapatite Powder ◽  
Calcium Phosphorus ◽  
Ph Cycling

The present study analyzed the action of sodium trimetaphosphate (TMP) and/or fluoride on hydroxyapatite. Hydroxyapatite powder was suspended in different solutions: deionized water, 500 µg F/mL, 1,100 µg F/mL, 1%TMP, 3%TMP, 500 µg F/mL plus 1%TMP and 500 µg F/mL plus 3%TMP. The pH value of the solutions was reduced to 4.0 and after 30 min, raised to 7.0 (three times). After pH-cycling, the samples were analyzed by X-ray diffraction and infrared spectroscopy. The concentrations of calcium fluoride, fluoride, calcium and phosphorus were also determined. Adding 1% or 3% TMP to the solution containing 500 µg F/mL produced a higher quantity of calcium fluoride compared to samples prepared in a 1,100 µg F/mL solution. Regarding the calcium concentration, samples prepared in solutions of 1,100 µg F/mL and 500 µg F/mL plus TMP were statistically similar and showed higher values. Using solutions of 1,100 µg F/mL and 500 µg F/mL plus TMP resulted in a calcium/phosphorus ratio close to that of hydroxyapatite. It is concluded that the association of TMP and fluoride favored the precipitation of a more stable hydroxyapatite.

BIOLOGICAL ACTIVITIES OF HAMYCIN

1966 ◽  
Vol 12 (2) ◽  
pp. 377-384
Author(s):  
A. C. Maniar ◽  
Sarala Mavdikar
Keyword(s):  
Candida Albicans ◽  
Antifungal Activity ◽  
Oral Dose ◽  
Biological Activities ◽  
The Body ◽  
In Vitro Activity ◽  
Body Tissues ◽  
High Concentrations ◽  
Albumin Molecule

After ad ministration of an oral dose to mice, hamycin, an antifungal antibiotic, penetrated the body tissues and eliminated Cryptococcus neoformans present in the lungs. Out of 11 polyenes (hamycin, aureofungin, trichomycin, etruscomycin, amphotericin B, pimaricin, mycostatin, candidin, candicidin, PA150, and filipin), hamycin and aureofungin showed the highest "in vitro" activity against Candida albicans. The antifungal activity of hamycin, PA150, and aureofungin was increased by the addition of serum, plasma, or crystalline albumins. This increase in activity can be used as an additional characteristic to differentiate some of the polyenes. We now believe that serum was responsible for our previous findings that "high concentrations of hamycin in the organs of mice were detected". It has been shown that the complete albumin molecule was required to increase the activity of hamycin. The possibility that serum globulins or other proteins may increase the hamycin activity is not ruled out by our experiments.

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