In vitro uptake of vitellogenin by follicles of the cockroach Nauphoeta cinerea: Comparison of artificial media with haemolymph media and role of vitellogenin concentration and of juvenile hormone

1988 ◽  
Vol 34 (6) ◽  
pp. 541-548 ◽  
Author(s):  
Helmut Kindle ◽  
Rolf König ◽  
Beatrice Lanzrein
1988 ◽  
Vol 27 (04) ◽  
pp. 151-153
Author(s):  
P. Thouvenot ◽  
F. Brunotte ◽  
J. Robert ◽  
L. J. Anghileri

In vitro uptake of 67Ga-citrate and 59Fe-citrate by DS sarcoma cells in the presence of tumor-bearing animal blood plasma showed a dramatic inhibition of both 67Ga and 59Fe uptakes: about ii/io of 67Ga and 1/5o of the 59Fe are taken up by the cells. Subcellular fractionation appears to indicate no specific binding to cell structures, and the difference of binding seems to be related to the transferrin chelation and transmembrane transport differences


1989 ◽  
Vol 64 (5) ◽  
pp. 957-967 ◽  
Author(s):  
P A Curmi ◽  
G Renaud ◽  
L Juan ◽  
B Chiron ◽  
A Tedgui

1983 ◽  
Vol 61 (7) ◽  
pp. 811-817 ◽  
Author(s):  
Daniela Rotin ◽  
Stephen S. Tobe

Juvenile hormone (JH) degradation in vitro and in vivo was studied in the viviparous cockroach Diploptera punctata. In vitro studies with juvenile hormone esterase (JHE) and "general" or 1-naphthyl acetate esterase (NAcE) revealed that diethyl-p-nitrophenylphosphate (paraoxon) inhibited both JHE and NAcE activity, but the latter was more sensitive and was completely inhibited at 0.1 mM. NAcE activity was resistant to inhibition with Triton X-100, whereas JHE activity in haemolymph of adult females was inhibited 100% at Triton X-100 concentration of 0.25%. Eighty percent inhibition of JHE activity in vivo was observed following injection of 0.2 μL Triton X-100. In contrast to the previously observed dose-dependant increase in JHE activity, NAcE activity did not increase following treatment of allatectomized females with the JH analogue ethyl-2E,4E-3,7,11-trimethyl-2,4-dodecadienoate (hydroprene). Hydroprene was not catabolized in haemolymph of D. punctata in vitro. The half-life of C16 JH (JH III) in the haemolymph, in vivo, was 1.65 h for day 5 females and 2 h for day 6 females.


1995 ◽  
Vol 39 (8) ◽  
pp. 1676-1682 ◽  
Author(s):  
E. M. Mtairag ◽  
H. Abdelghaffar ◽  
C. Douhet ◽  
M. T. Labro

Author(s):  
Janet H. Woodward ◽  
D. E. Akin

Silicon (Si) is distributed throughout plant tissues, but its role in forages has not been clarified. Although Si has been suggested as an antiquality factor which limits the digestibility of structural carbohydrates, other research indicates that its presence in plants does not affect digestibility. We employed x-ray microanalysis to evaluate Si as an antiquality factor at specific sites of two cultivars of bermuda grass (Cynodon dactvlon (L.) Pers.). “Coastal” and “Tifton-78” were chosen for this study because previous work in our lab has shown that, although these two grasses are similar ultrastructurally, they differ in in vitro dry matter digestibility and in percent composition of Si.Two millimeter leaf sections of Tifton-7 8 (Tift-7 8) and Coastal (CBG) were incubated for 72 hr in 2.5% (w/v) cellulase in 0.05 M sodium acetate buffer, pH 5.0. For controls, sections were incubated in the sodium acetate buffer or were not treated.


Author(s):  
David B. Warheit ◽  
Lena Achinko ◽  
Mark A. Hartsky

There is a great need for the development of a rapid and reliable bioassay to evaluate the pulmonary toxicity of inhaled particles. A number of methods have been proposed, including lung clearance studies, bronchoalveolar lavage analysis, and in vitro cytotoxicity tests. These methods are often limited in scope inasmuch as they measure only one dimension of the pulmonary response to inhaled, instilled or incubated dusts. Accordingly, a comprehensive approach to lung toxicity studies has been developed.To validate the method, rats were exposed for 6 hours or 3 days to various concentrations of either aerosolized alpha quartz silica (Si) or carbonyl iron (CI) particles. Cells and fluids from groups of sham and dust-exposed animals were recovered by bronchoalveolar lavage (BAL). Alkaline phosphatase, LDH and protein values were measured in BAL fluids at several time points postexposure. Cells were counted and evaluated for viability, as well as differential and cytochemical analysis. In addition, pulmonary macrophages (PM) were cultured and studied for morphology, chemotaxis, and phagocytosis by scanning electron microscopy.


2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.


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