The in vivo effects of silver nanoparticles on terrestrial isopods, Porcellio scaber, depend on a dynamic interplay between shape, size and nanoparticle dissolution properties

The Analyst ◽  
2019 ◽  
Vol 144 (2) ◽  
pp. 488-497 ◽  
Author(s):  
Sara Novak ◽  
Tea Romih ◽  
Barbara Drašler ◽  
Giovanni Birarda ◽  
Lisa Vaccari ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Porcellio Scaber ◽  
Terrestrial Isopods ◽  
Dissolution Properties ◽  
Low Concentrations ◽  
In Vivo Effects ◽  
Dynamic Interplay

The effects of exposure to low concentrations of AgNPs in model tissue, are the result of the interplay between size, shape and dissolution of ions from NPs.

RELEASE OF THYROTROPHIN IN VIVO AND IN VITRO BY SYNTHETIC NEUROHYPOPHYSIAL HORMONES

1964 ◽  
Vol 42 (1) ◽  
pp. 75-83 ◽  
Author(s):  
Frank S. LaBella
Keyword(s):  
Dose Response ◽  
In Vitro Release ◽  
Optimal Level ◽  
Response Curves ◽  
Low Concentrations ◽  
Pituitary Glands ◽  
In Vivo Effects ◽  
Synthetic Oxytocin

The influence of synthetic oxytocin and synthetic lysine-8-vasopressin on the release of thyrotrophin (TSH) from slices of the "basophilic" zone of bovine anterior pituitary glands was determined. Up to 10-fold stimulation of TSH release occurred in the presence of the peptide hormones at low concentrations (approximately 10−11 to 10−9 M). Concentrations greater than 10−9 M were less stimulatory, ineffective, or inhibitory. In general, vasopressin stimulated at lower concentrations than did oxytocin. The dose–response curve of oxytocin began to descend at lower concentrations than did that of vasopressin.Stimulation of I131 discharge from the thyroids of propylthiouracil (PTU)-treated, day-old chicks was produced by the intraperitoneal injection of as little as 4 ng vasopressin or 25 ng oxytocin. As the injected dose of either peptide was increased beyond an optimal level, there was less enhancement of I131 discharge, and, with further increases, inhibition. The decreasing response began with lower doses of oxytocin than of vasopressin. The similarities of the dose–response curves of thyroid I131 discharge and of in vitro release of TSH indicate that the in vivo effects of injected neurohypophysial peptides are mediated through the release of endogenous TSH.

Effect of low concentrations of cyanide on QOO2 of tissue slices

1963 ◽  
Vol 204 (2) ◽  
pp. 314-316 ◽  
Author(s):  
Adolfo Fernandez F. ◽  
Jorge Gonzalez-Quintana ◽  
Mauricio Russek
Keyword(s):  
Brain Slices ◽  
Sodium Cyanide ◽  
Tissue Respiration ◽  
Tissue Slices ◽  
Kidney Slices ◽  
Low Concentrations ◽  
Liver And Kidney ◽  
In Vivo Effects ◽  
Stimulation Of

The oxygen consumption of brain, liver, and kidney slices measured in the Warburg apparatus was not significantly depressed by concentrations of sodium cyanide of 0.2, 0.5, and 2 µg/ml. This last concentration is considered equal to that attained in the blood after an injection of 0.2 mg/kg, which produces remarkable in vivo effects described elsewhere. Therefore, the effects obtained in vivo cannot be due to the depression of tissue respiration by cyanide, but are probably caused by the stimulation of chemoreceptors. A concentration of 5 µg/ml notably reduced the QOO2 of brain slices, and 10 µg/ml reduced that of all three tissues. As reported by others, 50 µg/ml reduced the QOO2 of kidney slices by 80%. It is noteworthy that 0.2 µg/ml of NaCN produced a 40% increase ( P < 0.01) in the QOO2 of liver slices but only a 5–13% increase, not statistically significant, in brain slices.

In vivo effects of TGF-β1 in lung surfactant regulation, lung meachanics amd structure

Pneumologie ◽  
2014 ◽  
Vol 68 (06) ◽  
Author(s):  
E Lopez-Rodriguez ◽  
C Boden ◽  
S Knippenberg ◽  
A Pascual ◽  
J Perez-Gil ◽  
...  
Keyword(s):  
Lung Surfactant ◽  
In Vivo Effects ◽  
Tgf Β1

Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

1977 ◽  
Vol 16 (04) ◽  
pp. 157-162 ◽  
Author(s):  
C. Schümichen ◽  
B. Mackenbrock ◽  
G. Hoffmann
Keyword(s):  
Normal Saline ◽  
Half Life ◽  
Compound A ◽  
Short Half Life ◽  
Low Concentrations ◽  
The Stability ◽  
Kinetics Of ◽  
In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

99mTc-Sn-Pyrophosphate Complexes, an Investigation of its Possible Structures

1974 ◽  
Vol 13 (03) ◽  
pp. 252-257 ◽  
Author(s):  
K. Rörvik - Schümichen ◽  
G. Hoffmann ◽  
C. Schümichen
Keyword(s):  
In Vivo Distribution ◽  
Low Concentrations ◽  
Distribution Studies

SummaryAt least two different 99mTc-Sn-pyrophosphate complexes are formed, as it is shown by comparative in vivo distribution studies: A 2 : 2 Sn : pyrophosphate complex is predominant at higher concentrations. Only this complex shows bone seeking properties. A 2 : 1 Sn : pyrophosphate complex exists only at low concentrations. This complex shows no deposition in bone but in the kidneys. Which complex is predominant depends on the pyrophosphate concentration in the equilibrium. Both complexes are rapidly excreted by the kidneys.

Evaluation of Sacroiliac Wedge Rotation to Increase Acetabular Ventroversion

1999 ◽  
Vol 12 (04) ◽  
pp. 173-177 ◽  
Author(s):  
R. L. Aper ◽  
M. D. Brown ◽  
M. G. Conzemius
Keyword(s):  
Hip Joint ◽  
Hip Dysplasia ◽  
Clinical Effect ◽  
Pelvic Osteotomy ◽  
Alternative Method ◽  
Angular Measurements ◽  
Si Joint ◽  
In Vivo Effects ◽  
Canine Hip Dysplasia

SummaryTreatment of canine hip dysplasia (CHD) via triple pelvic osteotomy (TPO) is widely accepted as the treatment that best preserves the existing hip joint. TPO, however, has several important disadvantages. In an effort to avoid some of the difficulties associated with TPO an alternative method of creating acetabular ventroversion (AW) was sought. The purpose of this study was to explore the effects of placement of a wedge in the sacroiliac (SI) joint on A W and to compare this to the effect of TPO on A W . On one hemipelvis a 30° pelvic osteotomy plate was used for TPO. The contralateral hemipelvis had a 28° SI wedge inserted into the SI joint. Pre- and postsurgical radiographs of each pelvis were taken and the angular measurements were recorded. On average, the 28° SI wedge resulted in 20.9° of A W, the 30° canine pelvic osteotomy plate resulted in 24.9° A W . Significant differences were not found (p >0.05) between the two techniques. Sacroiliac wedge rotation effectively creates A W and has several theoretical advantages when compared to TPO. The in vivo effects of sacroiliac wedge rotation should be studied in order to evaluate the clinical effect of the technique.Sacroiliac wedge rotation was tested as an alternative method to increase the angle of acetabular ventroversion. This technique effectively rotated the acetabulum and has several theoretical advantages when compared to triple pelvic osteotomy.

Dichloroacetate--its in vivo effects on carbohydrate metabolism in the conscious dog

Diabetes ◽  
1980 ◽  
Vol 29 (9) ◽  
pp. 702-709 ◽  
Author(s):  
M. P. Diamond ◽  
R. C. Rollings ◽  
L. Erlendson ◽  
P. E. Williams ◽  
W. W. Lacy ◽  
...  
Keyword(s):  
Carbohydrate Metabolism ◽  
Conscious Dog ◽  
In Vivo Effects
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