Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Caproic acid”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1971

The effect of epsilon amino caproic acid and other inhibitors of proteolysis upon the response of human peripheral blood lymphocytes to phytohemagglutinin.

Previous work has suggested that intracellular proteolysis may play a role in lymphocyte stimulation. An inhibitor of proteolysis, epsilon amino caproic acid (EACA) was studied for its effect on the lymphocyte response to phytohemagglutinin (PHA). EACA was found to inhibit several parameters of lymphocyte stimulation (e.g. DNA, RNA, and protein synthesis as well as alterations in morphology) This inhibition was not due to diminished cellular viability and did not permanently impair the capacity of the lymphocyte to subsequently respond to PHA. Additionally, there was no evidence that this inhibition was due to other possible effects of EACA, such as alterations in Na(+) - K(+) transport, competitive amino acid deprivation or interference with PHA binding. Moreover, the inhibitors of proteolysis, tosyl arginine methyl ester (TAME), tosyl lysine chloromethyl ketone (TLCK), and tosyl phenyl-alanine chloromethyl ketone (TPCK), were also shown to inhibit lymphocyte stimulation.EACA was most effective when added during the first 24 hr of stimulation. Therefore, these experiments support the hypothesis that proteolysis is an essential step in the early phase of lymphocyte activation.

Aminocaproates↗
PubMed2004

Role of epsilon amino caproic acid in the management of haemophilic patients with inhibitors.

We managed bleeding crisis in 10 consecutive severe haemophilic patients with inhibitors (eight had an inhibitor level of >5 BU mL(-1)) mainly with the antifibrinolytic agent, i.e. epsilon amino caproic acid (EACA). EACA was used by local, oral or intravenous routes either in combination or separately. Five patients developed inhibitors postoperatively and among the remaining five, four had recurrent haemarthrosis or soft tissue bleeds and one patient presented with severe gastrointestinal bleeding without demonstrable lesion. In all the patients, addition of EACA to their management protocol resulted in stoppage and/or reduced frequency of bleeding. In six of 10 patients, the results were excellent; of these six patients, five developed inhibitors postoperatively. Although a reduction in the frequency of bleeding was observed in patients with haemarthrosis and soft tissue bleed, it was not spectacular and the patients required additional therapy. Hence the results could be described as poor. No patient needed to stop the medicine because of the side-effect of EACA. Symptoms like mild nausea and vertigo were seen as the side-effects of this medicine when high intravenous dosage was administered. EACA thus appears to be an excellent adjuvant therapy for haemophilic patients with inhibitors. Besides its well-recognized antifibrinolytic activity, EACA may have additional mechanisms of action in haemophilic patients with inhibitors. More extensive use of this cheap and safe product is warranted in haemophilic patients with inhibitors. If larger studies confirm this observation, then using antifibrinolytics will allow substantial reduction of FEIBA or activated prothrombin complex (APCC) usage in such patients without necessarily increasing the thrombotic complications or reduction of the clinical efficacy, when compared with higher dosage of FEIBA or APCC alone. This will lead to substantial financial savings in countries where up to 35% of severe haemophilia A patients develop inhibitors.

Adolescent↗
PubMed1979

Spontaneous subarachnoid hemorrhage complicated by communicating hydrocephalus: epsilon amino caproic acid as a possible predisposing factor.

An increased incidence of communicating hydrocephalus following subarachnoid hemorrhage has been observed on the neurosurgical service at Vanderbilt University Hospital during the past four years. This increase parallels the time interval during which epsilon amino caproic acid (Amicar) has been used in the preoperative regimen for intracranial aneurysms to prevent recurrent hemorrhage. Radiographic studies of 48 patients with subarachnoid hemorrhage not receiving Amicar were compared with 46 similar patients treated with this antifibrinolytic agent. In the series not treated with Amicar, a 17% incidence of dilated lateral ventricles was found, with 10% of the series being symptomatic from their hydrocephalus. A total of 43% of patients in the group treated with Amicar demonstrated dilated ventricles, with 31% of the group clinically symptomatic. Mechanisms of action of Amicar possibly implicated in this increased incidence of hydrocephalus are discussed.

Adult↗
PubMed2000

Epsilon amino caproic acid inhibits streptokinase-plasminogen activator complex formation and substrate binding through kringle-dependent mechanisms.

Lysine side chains induce conformational changes in plasminogen (Pg) that regulate the process of fibrinolysis or blood clot dissolution. A lysine side-chain mimic, epsilon amino caproic acid (EACA), enhances the activation of Pg by urinary-type and tissue-type Pg activators but inhibits Pg activation induced by streptokinase (SK). Our studies of the mechanism of this inhibition revealed that EACA (IC(50) 10 microM) also potently blocked amidolytic activity by SK and Pg at doses nearly 10000-fold lower than that required to inhibit the amidolytic activity of plasmin. Different Pg fragments were used to assess the role of the kringles in mediating the inhibitory effects of EACA: mini-Pg which lacks kringles 1-4 of Glu-Pg and micro-Pg which lacks all kringles and contains only the catalytic domain. SK bound with similar affinities to Glu-Pg (K(A) = 2.3 x 10(9) M(-1)) and to mini-Pg (K(A) = 3.8 x 10(9) M(-)(1)) but with significantly lower affinity to micro-Pg (K(A) = 6 x 10(7) M(-)(1)). EACA potently inhibited the binding of Glu-Pg to SK (K(i) = 5.7 microM), but was less potent (K(i) = 81.1 microM) for inhibiting the binding of mini-Pg to SK and had no significant inhibitory effects on the binding of micro-Pg and SK. In assays simulating substrate binding, EACA also potently inhibited the binding of Glu-Pg to the SK-Glu-Pg activator complex, but had negligible effects on micro-Pg binding. Taken together, these studies indicate that EACA inhibits Pg activation by blocking activator complex formation and substrate binding, through a kringle-dependent mechanism. Thus, in addition to interactions between SK and the protease domain, interactions between SK and the kringle domain(s) play a key role in Pg activation.

Aminocaproic Acid↗
PubMed1993

Intraperitoneal administration of leukotriene B4 (LTB4) and omega-guanidino caproic acid methane sulfonate (GCA) increased the survival of mice challenged with methicillin-resistant Staphylococcus aureus (MRSA).

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) very often complicate management of immunocompromised patients. We studied the effect of leukotriene B4 (LTB4) and epsilon-guanidino caproic acid methane sulfonate (GCA), on MRSA infection. Mice fed a 20% casein diet were intraperitoneally administered LTB4, GCA, or saline (control) daily for 30 days. On the 10th day of this treatment, mice were challenged with MRSA. The survival rate in the control group (20%) was significantly lower than the rates in the GCA (60%) and LTB4 (50%) groups, respectively (p < 0.05). There was a significant reduction of MRSA in the spleen and kidney of the survived mice in GCA group as against mice in the LTB4 and saline groups, indicating a better recovery in GCA group than the other groups. The results suggest that intraperitoneal administration of GCA and LTB4 may play a role in host defense mechanism during MRSA infections.

Animals↗
PubMed1979

Lack of functional recovery from spinal cord trauma following dimethylsulphoxide and epsilon amino caproic acid therapy in dogs.

The spinal cords of 20 normal dogs were exposed via dorsal laminectomies at L1 and damaged with a direct impact force of 440 g cm. One hour later treatment with dimethylsulphoxide (DMSO) was started on 10 dogs and with epsilon amino caproic acid (EACA) on the other 10 dogs. Administration of the DMSO ceased at 41 h after trauma and EACA at 49 h. The results showed that neither drug had a significant beneficial effect on the functional recovery of the spinal cords, when compared to a control group of similarly traumatised dogs.

Aminocaproates↗
PubMed1975

Cleavage of the third complement component (C3) and generation of the spasmogenic peptide, C3a, in human serum via the properdin pathway: demonstration of inhibitory as well as enhancing effects of epsilon-amino-caproic acid.

Human and guinea pig serum loses hemolytic activity of the third complement component (C3) during incubation at 37 degrees C. The loss is due to specific C3 cleavage involving the properdin system. This is concluded from the finding that C3 inactivation is prevented by EDTA, by elimination of properdin factor B, and unimpaired in C4 deficient guinea pig serum. In the presence of 1 M epsilon-amino-caproic acid (EACA) spontaneous C3 cleavage is considerably enhanced and accompanied by the appearance of biologically active C3a. Lower concentrations of EACA inhibit rather than enhance C3 cleavage in serum. The inhibitory effect of EACA is due to interference with the interaction of the properdin factors and their action on C3 as demonstrated in various systems: the assembly of an active C3-cleaving complex on zymosan, its regeneration after decay by factor D and factor B (GBG), cleavage of GBG by C3b and factor D in systems of purified components, and cleavage of C3 by preformed properdin complexes. Reactions involving the cobra venom factor were likewise depressed. In all these systems EACA was inhibitory even at 1M concentration. No single step in the development or action of an active properdin system was found to be enhanced by 1 M EACA. The enhancing effect of high concentrations of EACA on C3 cleavage in serum may be explained by its observed inhibition of C3b inactivator (C3bINA). This factor controls the properdin system by destroying C3b. In serum the inhibitory effect of 1 M EACA on C3bINA appears to allow escape of the properdin system from its control and thus to increase its net activity toward C3 despite inhibition of the enzymic reactions proper. At lower concentrations the effect of EACA on C3bINA is apparently less significant; therefore, at low concentrations of EACA, its inhibitory effects on C3 cleavage by the properdin system in serum prediominate.

Aminocaproates↗
PubMed1978

Enhancement of fibrinolysis in rabbits exposed to low and moderate levels of carbon monoxide inhibited by epsilon amino caproic acid.

The first (control) group of rabbits breathed ambient air whereas the second was exposed to low level carbon monoxide (CO, 50 ppm by volume) for 24 hr continuously for 8 weeks. The third group was exposed to 300 ppm CO for 4 weeks. The fourth group was exposed to 300 ppm CO for the same period of time as the third group but in addition they were also given epsilon amino caproic acid (EACA) orally, and the results compared to Group III. Per cent oxyhemoglobin (HbO2), per cent hemoglobin (Hb) and per cent carboxyhemoglobin (HbCO) were monitored in all groups. Tests of fibrinolysis were monitored and showed acceleration of the whole blood clot lysis and euglobulin lysis times (ELT). A fibrin plate test confirmed the increased lysis and serum fibrin and/or fibrinogen degradation products (FDP) were elevated in the CO exposed animals. No changes were observed in the same tests in the rabbits exposed to ambient air. The fourth group of animals receiving EACA showed inhibition of lysis and decrease in serum FDP. Alpha-1-antitrypsin and alpha-2-macroglobulin assays in all groups showed no change. Microscopic examination of the large vessels in these test groups showed endothelial damage which indicates a possible source for a plasminogen activator release, or lead to action of Hageman factor and activated plasma plasminogen proactivator.

Aminocaproates↗
PubMed1988

Stool caproic acid for screening of Clostridium difficile.

Clostridium difficile is the prime etiologic agent in the production of pseudomembranous colitis by its powerful cytotoxin. The most common test for the toxin is a tissue culture method with neutralization of cytopathic effect by a C. difficile antiserum. This method is expensive and requires a minimum of 72 hours before results can be obtained. Attempts to create a rapid method, counterimmunoelectrophoresis, enzyme-linked immunosorbent, latex agglutination, and fluorescent antibody test are fraught with many problems. This report describes a rapid method for the identification of C. difficile, using gas-liquid chromatography (GLC) for the demonstration of caproic acid, a product of the organisms fatty acid metabolism.

Bacterial Proteins↗
PubMed1986

On the interaction of the finger and the kringle-2 domain of tissue-type plasminogen activator with fibrin. Inhibition of kringle-2 binding to fibrin by epsilon-amino caproic acid.

The binding of tissue-type plasminogen activator (t-PA) to fibrin is mediated both by its finger domain and by its kringle-2 domain. In this report, we investigate the relative affinities of these domains for lysine. Human recombinant t-PA deletion-mutant proteins were prepared and their ability to bind to lysine-Sepharose was investigated. Mutants containing the kringle-2 domain bound to lysine-Sepharose, whereas mutants lacking this domain but containing the finger domain, the epidermal growth factor domain or the kringle-1 domain did not bind to lysine-Sepharose. Mutant proteins containing the kringle-2 domain could be specifically eluted from lysine-Sepharose with epsilon-amino caproic acid. This lysine derivative also abolished fibrin binding by the kringle-2 domain but had no effect on the fibrin-binding property of the finger domain. Thus, a lysine-binding site is involved in the interaction of the kringle-2 domain with fibrin but not in the interaction of the finger domain with fibrin. The implications of the nature of these two distinct interactions of t-PA with fibrin on plasminogen activation by t-PA will be discussed.

Aminocaproates↗
PubMedDate not supplied

Epsilon-amino-caproic acid in the treatment of Osler's hereditary angioneurotic edema.

This clinical entity described for the first time by Osler in 1888 presented a great therapeutic problem during many decades because of its severity. Landerman and later on Donaldson and Evans established the pathogenic mechanisms of this disease finding a deficiency in the inhibitor of the first activated component of complement, an alpha 2 aminoglycoprotein, to be the mechanism responsible of the same. More concretely, alterations in the plasmin, kinin and kallikrein systems are those that will lead to a change in vascular permeability with resultant tissue alterations. Four cases of hereditary angioneurotic edema are studied in female patients aged between 15 and 50 years and with family history consistent with angioneurotic familiar edema in which there were six cases of death due to edema of the glottis. Once the diagnosis had been made the patients were subjected to treatment with EACA at doses of 2.5 gm every 6 hours. The determinations of complement were similar in the four cases, with marked decreases in C4 and C1 inhibitor with a decrease in total complement in three cases. Regarding secondary effects, vomiting was found only in one cases, which as the dose was reduced did not necessitate termination of treatment. In summary, considering the results obtained in the cases above, we believe that due to its good tolerance and moderate cost, epsilon-amino-caproic acid at the abovementioned dosage is an excellent pharmacological agent in the treatment of Osler's hereditary angioneurotic edema.

Adolescent↗