THE SELECTIVE PROTEOLYTIC ENZYME INHIBITORY ACTION OF BENZETHONIUM CHLORIDE

1960 ◽  
Vol 38 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Ivan T. Beck ◽  
E. Pinter ◽  
R. D. McKenna ◽  
H. Griff

Acute hemorrhagic pancreatitis in humans is thought to be perpetuated by the autolytic processes catalyzed by trypsin and lipase. This study is an integral part of our search for trypsin and lipase inhibitors to be used in the treatment of this disease.Benzethonium chloride was found to inhibit tryptic activity in vitro. The proteolytic activity of rabbit's serum was inhibited, and the inhibition was most pronounced 6 to 12 hours after the subcutaneous injection of the compound. Fibrinolysin was also inhibited in vitro but benzethonium chloride had no inhibitory action on chymotrypsin, pepsin, or lipase.Serum proteins in vitro were precipitated only with very high concentrations of the compound. No significant protein changes were observed in sera of rabbits after the subcutaneous injection of the compound.

1960 ◽  
Vol 38 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Ivan T. Beck ◽  
E. Pinter ◽  
R. D. McKenna ◽  
H. Griff

Acute hemorrhagic pancreatitis in humans is thought to be perpetuated by the autolytic processes catalyzed by trypsin and lipase. This study is an integral part of our search for trypsin and lipase inhibitors to be used in the treatment of this disease.Benzethonium chloride was found to inhibit tryptic activity in vitro. The proteolytic activity of rabbit's serum was inhibited, and the inhibition was most pronounced 6 to 12 hours after the subcutaneous injection of the compound. Fibrinolysin was also inhibited in vitro but benzethonium chloride had no inhibitory action on chymotrypsin, pepsin, or lipase.Serum proteins in vitro were precipitated only with very high concentrations of the compound. No significant protein changes were observed in sera of rabbits after the subcutaneous injection of the compound.


1976 ◽  
Vol 231 (1) ◽  
pp. 14-19 ◽  
Author(s):  
M Barac-Nieto

Rat renal cortical slices were incubated with [1-(14)C]palmitate bound to 2.5% albumin. The following effects were found: a)1 mM palmitate utilization or oxidation to CO(2) varied according to the concentration of lactate in the media, it increased at 0.8 and 3.2 mM, was unchanged at 8 mM, and decreased at 16 mM. Esterification was stimulated at 3.2 mM lactate. b) Addition of glutamine (0.1 mM) instead of lactate stimulated incomplete and complete oxidation of palmitate (1 mM), whereas high medium glutamine (10 mM) inhibited palmitate (1 mM) utilization, esterification, and oxidation to CO(2) but increased its incomplete oxidation. The low rate of exogenous palmitate oxidation observed in this study and the finding that exogenous palmitate oxidation is only partially inhibited at very high concentrations of exogenous lactate or glutamine are consistent with the view that these exogenous substrates contribute little to the oxidative metabolism of rat renal cortex in vitro, which probably depends on the supply of substrates endogenous to the tissue.


1988 ◽  
Vol 34 (11) ◽  
pp. 2385-2386
Author(s):  
D S Sheriff ◽  
M el Fakhri

Abstract We describe a Libyan family with beta-thalassemia trait associated with unusually high concentrations of hemoglobin A2 and hypercholesterolemia. The family consists of the father, mother, and three sons. The marriage was consanguineous. The concentrations of total cholesterol and low-density lipoprotein cholesterol in serum were very high in two sons who also had widespread xanthomas. The erythrocyte membranes showed a high cholesterol/phospholipid ratio, with no significant susceptibility to lipid peroxidation in vitro.


1991 ◽  
Vol 129 (2) ◽  
pp. 221-226 ◽  
Author(s):  
P. A. Denning-Kendall ◽  
M. L. Wild ◽  
Wathes D. C.

ABSTRACT Bovine corpora lutea and ovarian stroma were analysed by high-performance liquid chromatography for catecholamine content. High concentrations (up to 102 nmol/g wet weight) were found in both 'central' stroma, containing many blood vessels, and 'peripheral' stroma. Central stroma contained noradrenaline and some dopamine, whereas peripheral stroma contained a higher proportion of dopamine and also significant amounts of 3,4-dihydroxyphenylacetic acid (DOPAC). Occasional samples of stroma had very high amounts of dopamine, suggesting that it is stored in specific regions. Corpora lutea, although devoid of direct innervation, contained dopamine (up to 5·3 nmol/g) and noradrenaline (up to 1·2 nmol/g). The average dopamine: noradrenaline molar ratio was 1·19 : 1 and the concentrations of dopamine and noradrenaline were highly correlated (P < 0·002). The concentration of dopamine was significantly higher in the early luteal phase of the oestrous cycle than during the rest of the cycle or in pregnancy. The levels of noradrenaline and dopamine present in corpora lutea are sufficient to modulate the production of both oxytocin and progesterone by luteal cells in vitro. Journal of Endocrinology (1991) 129, 221–226


1990 ◽  
Vol 149 (1) ◽  
pp. 425-437 ◽  
Author(s):  
BERND PELSTER ◽  
ROY E. WEBER

The influence of organic phosphates on the reduction in oxygen-carrying capacity at low pH (Root effect) in multiple fish haemoglobins has been analysed spectrophotometrically. In stripped haemolysates of carp, trout and eel, the Root effect in the presence of ATP was manifested below pH7.0. In the absence of phosphates, it was only found in trout haemolysate In the pH range between 8.5 and 6.1 no Root effect could be induced in the cathodic component (Hbl) of either trout or eel haemoglobin, even in the presence of very high concentrations of ATP or GTP. This was also true for component II (Hbll) of trout. The anodic component (HblV) of both species, however, exhibited a strong Root effect potentiated by NTP. At the same NTP/Hb4 concentration ratio, GTP was much more effective than ATP in both species The involvement of different haemoglobin components in the generation of high oxygen tensions in the fish swimbladder is discussed by comparing in vivo Root effect data obtained with an eel swimbladder preparation with in vitro data measured in eel blood and haemoglobin.


Blood ◽  
1991 ◽  
Vol 78 (5) ◽  
pp. 1241-1246
Author(s):  
RD Christensen ◽  
KW Liechty ◽  
JM Koenig ◽  
KR Schibler ◽  
RK Ohls

Very high concentrations of erythropoietin (epo), in clonogenic cultures, result in reduced production of neutrophils, and fetal progenitors are more sensitive to this effect of epo than are those of adults. However, the significance of this observation is unclear because no evidence of reduced neutrophil production has been presented following administration of recombinant epo to human or animal subjects. In the present study we injected newborn rats, beginning on the first day of life, with 20, 200, or 2,000 U epo/kg body weight, and measured serum epo concentrations after 2, 8, 24, or 48 hours. After selecting a dose that resulted in serum concentrations greater than 1,000 mU/mL (a concentration that resulted in down-modulation of neutrophil production from neonatal rat progenitors in vitro) other newborn rats were treated for 3 days with that dose (1,000 U epo/kg) or a vehicle control. Administration of epo resulted in increased hematocrits (P less than .001), reticulocyte counts (P less than .001), normoblasts/femur (P less than .05), and normoblasts/spleen (P less than .001). Recipients of epo also had more erythroid colony-forming units (CFU-E) (P less than .001) and higher CFU-E tritiated thymidine suicide rates (P less than .01) than did controls. However, femurs and spleens of epo recipients contained fewer postmitotic neutrophils (femur, P less than .01; spleen, P less than .01), proliferative neutrophils (femur, P less than .01; spleen, P less than .02), granulocyte-macrophage colony-forming units (CFU-GM) (P less than .005), and lower CFU-GM tritiated thymidine suicide rates (P less than .01). Seven and nine days after twice-daily administration of 2,000 U epo/kg, blood neutrophil concentrations had diminished (P less than .05). Thus, administration of high doses of recombinant epo to newborn rats resulted in diminished neutrophil production accompanying accelerated erythropoiesis.


2020 ◽  
Vol 21 (12) ◽  
pp. 4241
Author(s):  
Erman Popowski ◽  
Benjamin Kohl ◽  
Tobias Schneider ◽  
Joachim Jankowski ◽  
Gundula Schulze-Tanzil

Tendinopathy is a rare but serious complication of quinolone therapy. Risk factors associated with quinolone-induced tendon disorders include chronic kidney disease accompanied by the accumulation of uremic toxins. Hence, the present study explored the effects of the representative uremic toxins phenylacetic acid (PAA) and quinolinic acid (QA), both alone and in combination with ciprofloxacin (CPX), on human tenocytes in vitro. Tenocytes incubated with uremic toxins +/- CPX were investigated for metabolic activity, vitality, expression of the dominant extracellular tendon matrix (ECM) protein type I collagen, cell-matrix receptor β1-integrin, proinflammatory interleukin (IL)-1β, and the ECM-degrading enzyme matrix metalloproteinase (MMP)-1. CPX, when administered at high concentrations (100 mM), suppressed tenocyte metabolism after 8 h exposure and at therapeutic concentrations after 72 h exposure. PAA reduced tenocyte metabolism only after 72 h exposure to very high doses and when combined with CPX. QA, when administered alone, led to scarcely any cytotoxic effect. Combinations of CPX with PAA or QA did not cause greater cytotoxicity than incubation with CPX alone. Gene expression of the pro-inflammatory cytokine IL-1β was reduced by CPX but up-regulated by PAA and QA. Protein levels of type I collagen decreased in response to high CPX doses, whereas PAA and QA did not affect its synthesis significantly. MMP-1 mRNA levels were increased by CPX. This effect became more pronounced in the form of a synergism following exposure to a combination of CPX and PAA. CPX was more tenotoxic than the uremic toxins PAA and QA, which showed only distinct suppressive effects.


1973 ◽  
Vol 51 (10) ◽  
pp. 2004-2006 ◽  
Author(s):  
D. R. Jones

The inhibitory action of three systemic fungicides (Benlate, Hoe 6053, and Milstem) on the growth of axenic cultures of the carnation rust fungus, Uromyces dianthi, was assessed. The rust- and smut-specific fungicide (Hoe 6053) was found to inhibit growth when present in the agar medium in very low concentrations, while moderate concentrations of the wide range fungicide (Benlate), and high concentrations of the powdery mildew-specific fungicide (Milstem) were needed for inhibition. The results indicated the possible use of U. dianthi in future in vitro fungicide screening programs and mode-of-action studies.


1988 ◽  
Vol 29 (5) ◽  
pp. 585-588 ◽  
Author(s):  
E. V. Lang ◽  
E. C. Lasser

The effect of ioxaglate and diatrizoate on per cent granulocyte adherence to nylon fibers was investigated in blood to which contrast medium was added in vitro and in blood from patients undergoing angiography. Very high concentrations of contrast medium, added to blood in vitro, directly abolished granulocyte adherence to nylon fibers. Intraaortic bolus injections of ioxaglate, but not of saline, transiently increased granulocyte concentrations in the femoral vein. Fractional granulocyte adherence to nylon fibers increased significantly above the baseline when angiographic dosages of contrast medium were diluted by circulation within the human body. On the other hand, dilute concentrations of contrast medium had no effect on per cent granulocyte adherence when added to whole blood in vitro. This indicates that the increased adherence produced in vivo is an indirect effect, which, usually, cannot be simulated in vitro.


1999 ◽  
Vol 65 (5) ◽  
pp. 2049-2053 ◽  
Author(s):  
M. Cristina del Rincón-Castro ◽  
José Barajas-Huerta ◽  
Jorge E. Ibarra

ABSTRACT Most strains of the insecticidal bacterium Bacillus thuringiensis have a combination of different protoxins in their parasporal crystals. Some of the combinations clearly interact synergistically, like the toxins present in B. thuringiensis subsp. israelensis. In this paper we describe a novel joint activity of toxins from different strains ofB. thuringiensis. In vitro bioassays in which we used pure, trypsin-activated Cry1Ac1 proteins from B. thuringiensissubsp. kurstaki, Cyt1A1 from B. thuringiensissubsp. israelensis, and Trichoplusia niBTI-Tn5B1-4 cells revealed contrasting susceptibility characteristics. The 50% lethal concentrations (LC50s) were estimated to be 4,967 of Cry1Ac1 per ml of medium and 11.69 ng of Cyt1A1 per ml of medium. When mixtures of these toxins in different proportions were assayed, eight different LC50s were obtained. All of these LC50s were significantly higher than the expected LC50s of the mixtures. In addition, a series of bioassays were performed with late first-instar larvae of the cabbage looper and pure Cry1Ac1 and Cyt1A1 crystals, as well as two different combinations of the two toxins. The estimated mean LC50 of Cry1Ac1 was 2.46 ng/cm2 of diet, while Cyt1A1 crystals exhibited no toxicity, even at very high concentrations. The estimated mean LC50s of Cry1Ac1 crystals were 15.69 and 19.05 ng per cm2 of diet when these crystals were mixed with 100 and 1,000 ng of Cyt1A1 crystals per cm2 of diet, respectively. These results indicate that there is clear antagonism between the two toxins both in vitro and in vivo. Other joint-action analyses corroborated these results. Although this is the second report of antagonism between B. thuringiensis toxins, our evidence is the first evidence of antagonism between toxins from different subspecies of B. thuringiensis (B. thuringiensis subsp. kurstaki and B. thuringiensis subsp. israelensis) detected both in vivo and in vitro. Some possible explanations for this relationship are discussed.


Sign in / Sign up

Export Citation Format

Share Document