A time course study on the “in vitro” effects of T3 and testosterone on androgen and estrogen receptors in peripuberal primary rat Sertoli cells

2009 ◽  
Vol 105 (04) ◽  
pp. 218-224 ◽  
Author(s):  
D. Sisci ◽  
M. L. Panno ◽  
M. Salerno ◽  
M. Maggiolini ◽  
V. Pezzi ◽  
...  
Weed Science ◽  
1971 ◽  
Vol 19 (3) ◽  
pp. 248-253
Author(s):  
I. Y. Mostafa ◽  
S. C. Fang

A time course study on the in vitro effect of 10–4 M (2,4-dichlorophenoxy)acetic acid (2,4-D) on the metabolism and incorporation of specific 14C-labeled glucose into pea (Pisum sativum L., var. Alaska) and corn (Zea mays L., var. Golden Cross) tissues showed a preferential release of C-1 as CO2 which was affected by 2,4-D. The glucuronic acid pathway was stimulated greatly in pea roots and slightly in corn stems; it was inhibited in corn roots. The pentose phosphate pathway was affected in an opposite pattern. The incorporation of both labeled carbon atoms into alcohol-insoluble residue was also affected by 2,4-D. The degree of effect, however, varied from pea to corn and from roots to stems. Analysis of the alcohol-soluble fraction revealed different effects of 2,4-D on labeling of some of the amino acids, an increase in fructose content, and an accumulation of malic acid.


Reproduction ◽  
2014 ◽  
Vol 148 (3) ◽  
pp. 259-270 ◽  
Author(s):  
Georgios Michailidis ◽  
Maria Anastasiadou ◽  
Edith Guibert ◽  
Pascal Froment

Sertoli cells (SCs) play an important physiological role in the testis, as they support, nourish, and protect the germ cells. As protection of the developing spermatozoa is an emerging aspect of reproductive physiology, this study examined the expression pattern of innate immune-related genes, including avian β-defensins (AvBDs), Toll-like receptors (TLRs), and cytokines, and investigated the time course of an inflammatory response in rooster SCs triggered by exposure to the bacterial endotoxin lipopolysaccharide (LPS). SCs were isolated from 6-week-old chicken, culturedin vitro, and stimulated with 1 μg/ml LPS at different time courses (0, 6, 12, 24, and 48 h). Data on expression analysis revealed that all ten members of the chickenTLRfamily, nine members of theAvBDfamily, as well as eight cytokine genes were expressed in SCs. Quantitative real-time PCR analysis revealed that LPS treatment resulted in significant induction of the expression levels of sixTLRs, sixAvBDs, and four cytokine genes, while two cytokine genes were downregulated and two other genes were unchanged. The increasing interleukin 1β (IL1β) production was confirmed in the conditioned medium. Furthermore, the phagocytosis of SCs was increased after LPS treatment. In conclusion, these findings provide evidence that SCs express innate immune-related genes and respond directly to bacterial ligands. These genes represent an important component of the immune system, which could be integrated into semen, and present a distinctive constituent of the protective repertoire of the testis against ascending infections.


2004 ◽  
Vol 177 (2) ◽  
pp. 79-86 ◽  
Author(s):  
Sarah Mackay ◽  
Louise Willerton ◽  
Christine L. Ballingall ◽  
Nicola J.S. Henderson ◽  
Robert A. Smith

1993 ◽  
Vol 183 (1) ◽  
pp. 101-113 ◽  
Author(s):  
K. M. Gilmour ◽  
C. P. Ellington

The amplitude and time course of muscle length changes were examined in vivo in tethered, flying bumblebees Bombus lucorum. A ‘window’ was cut in the dorsal cuticle and aluminium particles were placed on the exposed dorsal longitudinal muscle fibres. Muscle oscillations were recorded using high-speed video and a high-magnification lens. The amplitude of muscle length changes was 1.9 % (s.d.=0.5 %, N=7), corresponding to the commonly quoted strain of 1–3 % for asynchronous muscle. Higher harmonics, particularly the second, were found in the muscle oscillations and in the wing movements. The second harmonic for wing movements was damped in comparison to that for muscle length changes, probably as a result of compliance in the thoracic linkage. Inclusion of the second harmonic in the driving signal for in vitro experiments on glycerinated fibres generally resulted in a decrease in the work and power, but a substantial increase was found for some fibres.


1999 ◽  
Vol 65 (9) ◽  
pp. 4261-4263 ◽  
Author(s):  
B. D. Tall ◽  
J. F. La Peyre ◽  
J. W. Bier ◽  
M. D. Miliotis ◽  
D. E. Hanes ◽  
...  

ABSTRACT The in vitro effects of the Perkinsus marinus serine protease on the intracellular survival of Vibrio vulnificusin oyster hemocytes were examined by using a time-course gentamicin internalization assay. Results showed that protease-treated hemocytes were initially slower to internalize V. vulnificus than untreated hemocytes. After 1 h, the elimination of V. vulnificus by treated hemocytes was significantly suppressed compared with hemocytes infected with invasive and noninvasive controls. Our data suggest that the serine protease produced byP. marinus suppresses the vibriocidal activity of oyster hemocytes to effectively eliminate V. vulnificus, potentially leading to conditions favoring higher numbers of vibrios in oyster tissues.


1987 ◽  
Vol 242 (1) ◽  
pp. 235-243 ◽  
Author(s):  
S W Mercer ◽  
D H Williamson

Depression of carbohydrate digestion by oral administration of acarbose, a glucosidase inhibitor, led to a 75% inhibition of the re-activation of lipogenesis in vivo in the mammary gland of 18 h-starved lactating rats refed with 5 g of chow diet. Rates of [1-14C]glucose incorporation in vitro into lipid and CO2 in mammary-gland acini isolated from refed animals were elevated compared with acini from starved rats, but acarbose treatment completely prevented this stimulation. Gastric intubation of glucose led to a large stimulation of lipogenesis in the mammary gland of starved lactating rats, similar to that induced by refeeding with chow diet; this was dependent on the amount of glucose given and the time elapsed between glucose administration and injection of 3H2O for the measurement of lipogenesis. The switch-on of lipogenesis in the mammary gland of starved lactating rats, by refeeding or by intubation of glucose, was associated with a decrease in the ratio of [glucose 6-phosphate]/[fructose 1,6-bisphosphate] in the gland, indicative of an increase in phosphofructokinase activity. A time-course study revealed that the ratio decreased rapidly over the first 30 min of chow refeeding, after which a large surge in lipogenesis was seen. Acarbose, given 25 min after the onset of refeeding, led to a stepwise increase in the ratio, in parallel with the observed decrease in lipogenic activity. It is concluded that the control of lipogenesis in the mammary gland is closely linked to the availability of dietary carbohydrate. An important site of regulation of lipogenesis in the gland appears to be at the level of phosphofructokinase. A possible role of insulin in the regulation of phosphofructokinase activity, and the acute modulation of insulin-sensitivity in the gland during the starved-refed transition, are discussed.


Sarcoma ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Matthias J. E. Arlt ◽  
Ingo J. Banke ◽  
Josefine Bertz ◽  
Ram Mohan Ram Kumar ◽  
Roman Muff ◽  
...  

Metastasis is the major cause of death of osteosarcoma patients and its diagnosis remains difficult. In preclinical studies, however, forced expression of reporter genes in osteosarcoma cells has remarkably improved the detection of micrometastases and, consequently, the quality of the studies. We recently showed that Dunn cells equipped with alacZreporter gene disseminated from subcutaneous primary tumors as frequently as their highly metastatic subline LM8, but only LM8 cells grew to macrometastases. In the present time-course study, tail-vein-injected Dunn and LM8 cells settled within 24 h at the same frequency in the lung, liver, and kidney of mice. Furthermore, Dunn cells also grew to macrometastases, but, compared to LM8, with a delay of two weeks in lung and one week in liver and kidney tissue, consistent with prolonged survival of the mice. Dunn- and LM8-cell-derived ovary and spine metastases occurred less frequently.In vitro, Dunn cells showed less invasiveness and stronger contact inhibition and intercellular adhesion than LM8 cells and several cancer- and dormancy-related genes were differentially expressed. In conclusion, Dunn cells, compared to LM8, have a similar capability but a longer latency to form macrometastases and provide an interesting new experimental system to study tumor cell dormancy.


2001 ◽  
Vol 79 (8) ◽  
pp. 879-885
Author(s):  
M Filion ◽  
M St-Arnaud ◽  
C Guillon ◽  
C Hamel ◽  
S H Jabaji-Hare

Various experimental systems have been developed to study the mycorrhizosphere. In this study, a microcosm experimental system was constructed and optimized to simulate the environments of the mycorrhizosphere: the rhizosphere, the mycosphere, and the bulk soil, using beans (Phaseolus vulgaris L.) as host plants. We investigated, in a time-course study, the effect of axenically in vitro produced spore inoculum and root segment inoculum of the arbuscular mycorrhizal fungus, Glomus intraradices Schenck & Smith, on extraradical mycelium development, rapidity of mycorrhizal colonization, and plant growth under nonsterile soil conditions. Three concentrations of in vitro produced spores and three concentrations of root segment inoculum produced from open pot cultures were used. The two highest concentrations of spores used as inoculum resulted in faster and more abundant colonization than when root segments were used. A significant correlation was obtained between hyphal densities present in the rhizosphere and mycosphere compartments, and the amount of spore inoculum used. The densities of roots in the rhizosphere compartment and hyphae in the rhizosphere and mycosphere compartments were comparable with field-grown plants; thus, the system realistically mimics a natural mycorrhizosphere. The use of the microcosm described in this study, in combination with the in vitro produced spore inoculum of G. intraradices, represents an experimental approach well adapted for studying the microbial ecology of the mycorrhizosphere.Key words: AMF, microbial ecology, inoculum, mycorrhiza, mycorrhizosphere.


1990 ◽  
Vol 258 (1) ◽  
pp. R99-R103
Author(s):  
M. Leite ◽  
W. N. Suki

The V2-selective analogue of arginine vasopressin (AVP), dDAVP, has been used to distinguish between the effects of V1- and V2-receptor activation by AVP in different cell types of the kidney. Based on studies showing different effects of AVP and dDAVP on prostaglandin secretion, and also on cytosolic Ca2+, we designed a comparative time-course study of both agonists on rabbit microdissected cortical collecting tubules (CCT) microperfused in vitro at 38 degrees C. Plots of the effects of AVP (10 microU/ml or 2.2 x 10(-11) M and 100 microU/ml or 2.2 x 10(-10) M) and dDAVP (10 microU/ml or 0.8 x 10(-11) M) on osmotic water permeability (Pf) at comparable antidiuretic activities, revealed an increase of Pf that was maintained for as long as 170 min of hormone exposure. Also the magnitude of increase in Pf and the time required to achieve the more sustained phase of response were comparable, with no significant difference between the two agonists. These results clearly demonstrate a stable response of rabbit CCT to AVP and dDAVP at physiological temperature, and they reveal no evidence for a difference between the native hormone AVP and its V2 selective analogue on the net hydrosmotic response of the CCT.


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