scholarly journals Inhibitory Effect of Heparin on Collagen Fiber Formation in Hepatic Cells in Culture.

1997 ◽  
Vol 22 (5) ◽  
pp. 533-538 ◽  
Author(s):  
Kazumi Akimoto ◽  
Masashi Ikeda ◽  
Kenji Sorimachi
1976 ◽  
Vol 20 (1) ◽  
pp. 199-206
Author(s):  
T.J. Yang ◽  
J.B. Dale ◽  
R. Machanoff

Prostaglandins E1, E2, and F2alpha (PGE1, PGE2, and PGF2alpha) were shown to inhibit the growth of mouse leukaemia lymphoblasts L5178Y in culture. The effects of PGE1 and PGE2 were greater than that of PGF2alpha. PGE1 and PGE2, at the concentration of 100 mug per ml showed significant inhibitory effects on the rates of incorporation of tritiated thymidine, uridine and leucine. At concentrations of 50 and 25 mug per ml, there was significant inhibition of thymidine and uridine incorporation, but not of leucine, PGF2alpha showed significant inhibition of thymidine and uridine incorporation but not leucine incorporation, in all 3 concentrations studied (100, 50, and 25 mug/ml). The ability of the cells to form colonies in soft agar was significantly inhibited by PGE1 and PGE2 at concentrations as low as 1–8 mug/ml. For F2alpha, however, a concentration as high as 56mug/ml was required to show inhibitory effect, but at 1–8 mug/ml it was found to be stimulatory.


Antibiotics ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 84 ◽  
Author(s):  
Anna Brandtner ◽  
Mirjam Bachler ◽  
Dietmar Fries ◽  
Martin Hermann ◽  
Jacqueline Ruehlicke ◽  
...  

Tigecycline offers broad anti-bacterial coverage for critically ill patients with complicated infections. A described but less researched side effect is coagulopathy. The aim of this study was to test whether tigecycline interferes with fibrinogen polymerization by peripheral interactions. To study the effect of unmetabolized tigecycline, plasma of healthy volunteers were spiked with increasing concentrations of tigecycline. In a second experimental leg, immortalized human liver cells (HepG2) were treated with the same concentrations to test an inhibitory effect of hepatic tigecycline metabolites. Using standard coagulation tests, only the activated thromboplastin time in humane plasma was prolonged with increasing concentrations of tigecycline. Visualization of the fibrin network using confocal live microscopy demonstrated a qualitative difference in tigecycline treated experiments. Thrombelastometry and standard coagulation tests did not indicate an impairment of coagulation. Although the discrepancy between functional and immunologic fibrinogen levels increased in cell culture assays with tigecycline concentration, fibrinogen levels in spiked plasma samples did not show significant differences determined by functional versus immunologic methods. In our in vitro study, we excluded a direct effect of tigecycline in increasing concentrations on blood coagulation in healthy adults. Furthermore, we demonstrated a rapid loss of mitochondrial activity in hepatic cells with supra-therapeutic tigecycline dosages.


Endocrinology ◽  
1997 ◽  
Vol 138 (10) ◽  
pp. 4401-4409 ◽  
Author(s):  
M. Quintela ◽  
R. M. SeñarÍs ◽  
C. Diéguez

Abstract Treatment of hypothalamic cells in monolayer culture with transforming growth factor-β1 (TGFβ1) significantly reduced both basal and cAMP-induced somatostatin messenger RNA (mRNA) levels and somatostatin secretion. This inhibitory effect was dose- and time-dependent and not mediated by glial cells, as it was also observed in glial-free hypothalamic cell cultures treated with cytosine arabinonucleoside. TGFβ2 and -β3 mimicked the actions of TGFβ1, which indicated that the three isoforms of the TGFβ family expressed in the central nervous system displayed similar effects on the somatostatinergic neurons. The blockade of synthesis of proteins with either cycloheximide or puromycin for 24 h prevented the inhibitory effect of TGFβ1 on somatostatin mRNA. This implied that the reduction of this mRNA by TGFβ1 required de novo protein synthesis. We next studied whether TGFβ1 acted at the transcriptional or posttranscriptional level by altering the stability of somatostatin mRNA. Examination of the rate of disappearance of somatostatin mRNA by Northern blot, after inhibition of mRNA transcription with either actinomycin D (AcD) or 5,6-dichloro-1β-ribofuranosyl benzimidazole revealed that TGFβ1 did reduce the stability of somatostatin mRNA. This effect was observed when we pretreated the cultures with TGFβ1 4 h before the addition of AcD, but not when we administered TGFβ1 simultaneously with AcD or 5,6-dichloro-1β-ribofuranosyl benzimidazole. Altogether these results demonstrated that the treatment of hypothalamic cells in culture with TGFβ1, TGFβ2, or TGFβ3 resulted in a decrease in somatostatin mRNA levels and somatostatin secretion. TGFβ1 reduced the steady state levels of somatostatin mRNA by inducing the synthesis of a protein (s), that appears to accelerate the degradation of the mRNA of somatostatin. Whether TGFβ1 has additional effects on the transcription of the somatostatin gene will require further study.


2019 ◽  
Vol 30 (6) ◽  
pp. 599-606
Author(s):  
Carolina Maschietto Pucinelli ◽  
Raquel Assed Bezerra da Silva ◽  
Luã Lopes Borges ◽  
Alberto Tadeu do Nascimento Borges ◽  
Paulo Nelson-Filho ◽  
...  

Abstract The aim of this study was to evaluate the subcutaneous connective tissue response of isogenic mice after implantation of different glass ionomer-based cements (EQUIA® Forte Fil, EQUIA® Fil and Ketac™ Universal Aplicap™). Eighty-seven isogenic BALB/c mice were allocated in 12 groups, 9 were considered as experimental groups (Ketac, E. Fil and E. Forte at 7, 21 and 63 days) and 3 controls (empty polyethylene tubes at 7, 21 and 63 days). After the experimental periods, the subcutaneous connective tissue surrounding the implanted material was removed and subjected to histotechnical processing and staining with hematoxylin and eosin. A histopathological description of the tissue reaction surrounding each material and a semi-quantitative analysis of collagen fiber formation and inflammatory infiltrate were performed. Additionally, the thickness of the granulomatous tissue in contact with each material was measured. Data were analyzed statistically (α=0.05) by the Kruskal-Wallis test, followed by Dunn post-test. Initially, the collagen fiber formation was not different among all the tested materials (p>0.05) but was different at 21 days with the control group presenting the most advanced stage of collagen fiber formation. At 63 days, EQUIA® Forte Fil group showed the most advanced stage of collagen fiber formation, compared to EQUIA® Fil group (p<0.05). The inflammatory infiltrate was not different among the tested materials in any experimental period (p>0.05). The thickness of the granulomatous tissue was greater in the E. Forte group, compared to control in all periods. All glass ionomer-based cements showed tissue compatibility, according to the evaluated parameters.


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