Effects of ethanol on structure and solubility of potato proteins and the effects of its presence during the preparation of a protein isolate.

In this study, a protein isolate with a high solubility at neutral pH was prepared from industrial potato juice by precipitation at pH 5 in the presence of ethanol. The effects of ethanol itself and the effects of its presence during precipitation on the properties of various potato protein fractions were examined. The presence of ethanol significantly reduced the denaturation temperature of potato proteins, indicating that the preparation of this potato protein isolate should be performed at low temperature in order to retain a high solubility.

Effects of pH and heat treatments on the structure and solubility of potato proteins in different preparations.

The soluble potato proteins are mainly composed of patatin and protease inhibitors. Using DSC and both far-UV and near-UV CD spectroscopy, it was shown that potato proteins unfold between 55 and 75 degrees C. Increasing the ionic strength from 15 to 200 mM generally caused an increase in denaturation temperature.

Purification and substrate specificity of transglutaminases from blood and Streptoverticillium mobaraense.

A procedure for a fast and simple purification of bovine plasma transglutaminase was developed, which resulted in a homogeneous enzyme preparation. Two different procedures were developed for the purification of pig erythrocyte transglutaminase, both of which resulted in partial purification. Both enzymes were used in cross-linking reactions of alpha-lactalbumin, beta-lactoglobulin, bovine serum albumin, casein, hemoglobin, glycinin, and myosin.

Training for more accurate visual fat estimation in meat.

Much animal fat in the diet is contained in meat. As fat intake is considered too high in western societies, a more fat-conscious attitude may be desirable. One of the parties involved is the butcher, who sells fresh meat directly to the consumer.

Shelf-life of vacuum-packaged wild boar meat in relation to that of vacuum-packaged pork: Relevance of intrinsic factors.

In order to study the factors influencing the relatively poor keepability of pork compared with beef, a study with wild boar meat was carried out. Microbiological and sensory quality traits of vacuum-stored wild boar (Sus scrofa scrofa) cuts of M. longissimus dorsi (longissimus) at 0°C were determined after 1, 10, 28, 42, 56, 70, 84 and 98 days and of tenderloins after 3, 35, 49 and 63 days.

The effect of scalding on subcutaneous and ham temperatures and ultimate pork quality.

Scalding of pig carcasses (n = 34) at 60°C for a period of at least 5·5 to 7·5 min gave satisfactory dehairing results, with the exception of autumn hair for which a longer period (9 mins) was required. Temperature curves were recorded for a subcutaneous position in the ham (n = 26) between the rind and the underlying fat layer. These showed a curve starting at about 30·8°C and increasing to an asymptotic value of 53°C during scalding.

Haematological and clinico-chemical profiles of barrows at the farm and at slaughter.

Haematological and clinico-chemical profiles of blood of healthy stress-resistant swine collected at the farm and at slaughter were determined to investigate whether values of blood variables can be used to establish stress. The values of most variables investigated showed highly significant changes. It is concluded that haematological and clinico-chemical values may be useful in studies to detect, quantify and reduce stress-provoking conditions in stress-resistant swine.

Characterization of changes in psychometric colour attributes of comminuted porcine lean meat during processing.

Changes in colour during the processing of a comminuted porcine lean meat system were characterized using the psychometric colour attributes lightness L (∗)) hue (h (∗))and chroma (C (∗)). The effects of processing temperature, nitrite and air pressure during comminution were examined. The pattern of changes as a function of processing time for L (∗) and C (∗), but not for h (∗), showed clear dependence on processing temperature (15, 30, 40, 50 and 60°C).

alpha 2-Antiplasmin Enschede: dysfunctional alpha 2-antiplasmin molecule associated with an autosomal recessive hemorrhagic disorder.

alpha 2-Antiplasmin (alpha 2-AP) is a major fibrinolysis inhibitor, whose complete, congenital absence has been found to be associated with a distinct hemorrhagic diathesis. We studied a 15-yr-old male with a hemorrhagic diathesis after trauma from early childhood on. This bleeding tendency was associated with a minimal alpha 2-AP level recorded functionally in the immediate plasmin inhibition test: less than or equal to 4% of normal.

Characterization and fibrin-binding properties of different molecular forms of pro-urokinase from a monkey kidney cell culture.

Culture fluid of a monkey kidney cell culture was harvested every two days, for a two week period, in order to obtain urokinase in the zymogen form. Pro-urokinase was isolated by immunoadsorption chromatography and gel filtered on Sephadex G-150, which resulted in three peaks with pro-urokinase activity. SDS-polyacrylamide gel electrophoresis showed that the first peak contained 55 kd pro-urokinase, aggregated with high molecular weight contaminants, whereas the second and third peaks consisted of almost pure 55 kd and 30 kd pro-urokinase, respectively.

Appropriate milieu for the assay of alpha-2-antiplasmin activity with chromogenic substrates.

Inhibition reference curves for alpha 2-antiplasmin showed a deviation from linearity at low inhibitor concentrations using the chromogenic substrate S-2251. Extrapolation of these curves to zero inhibition gave higher amidolytic activities than actually recorded with the free enzyme plasmin. It was further found that comparison of purified alpha 2-antiplasmin and that in plasma was prevented by the deviation.

Fibrinolytic activators and inhibitors in terminal renal insufficiency and in anephric patients.

Fibrinolytic factors were measured before and after DDAVP-infusion in 18 patients on chronic, regular haemodialysis, 11 of whom underwent bilateral nephrectomy, and in 7 patients in whom non-functioning kidneys were still present. Baseline fibrinolytic activity was normal or high in all but two cases. Before haemodialysis, the response to DDAVP-infusion was greatly reduced in the majority of patients as compared with healthy controls, irrespective of the baseline level.

Comparison of enzymes of tears, lacrimal gland fluid and lacrimal gland tissue in the rat.

A variety of enzymes were identified in rat tears and lacrimal gland fluid. The use of a tapered glass cannula in the opening of the excretory duct was found to be an useful method to collect samples of rat lacrimal gland fluid, i.e.

The influence of L-asparaginase therapy on the fibrinolytic system.

Fibrinolytic factors were assessed during L-asparaginase administration, to study whether their changes may predispose to a haemorrhagic or thrombotic diathesis. The total level of alpha 2-antiplasmin declined, as well as the ratio of the plasminogen-binding form of alpha 2-antiplasmin to the non-plasminogen-binding form. After cessation of L-asparaginase administration, the ratio increased to 1.

Stanozolol-induced changes in fibrinolysis and coagulation in healthy adults.

The effect of orally-administered stanozolol, 5 mg b.d. on fibrinolysis, coagulation and on various haematological and biochemical parameters have been studied in 16 healthy adults, 8 males and 8 females.

Intrinsic plasma fibrinolysis: involvement of urokinase-related activity in the factor XII-independent plasminogen proactivator pathway.

A portion of human blood fibrinolytic activity can be quenched by antibodies to urokinase. We attempted to identify this portion and its position in the three pathways (extrinsic, intrinsic factor XII dependent, and intrinsic factor XII independent) of plasminogen activator activity that have been defined in the DEFs of plasma. Activity quenching in various plasmas (including plasma adsorbed by agarose-bound AUK) demonstrated the involvement of a discrete activator activity of 40 to 50 BAU/ml with little variation among individuals (43 +/- 6 (SD) BAU/ml, n = 13).

Fibrinolytic activity of the gastric mucosa in Ménétrièr's disease.

Biopsies of the gastric mucosa were collected from two patients with Ménétrièr's disease before, during, and after treatment with cimetidine and studied for fibrinolytic activity. The fibrinolytic activity in the homogenates or in the potassium thiocyanate soluble fractions increased markedly during the treatment. Immunological characterization of the activity indicated that its major component was an endothelium-derived type of plasminogen activator, and that the increase in activity was caused solely by an increase in the concentration of this component.

A new life-long hemorrhagic disorder due to excess plasminogen activator.

A life-long bleeding disorder is described, characterized by hemorrhage occurring after surgery, injury, or dental extraction, and finally by spontaneous intracerebral bleeding. No abnormality of platelet function or plasma coagulation was demonstrable, but grossly enhanced overall fibrinolytic activity was present. The patient had, additionally, a hyperlipidemia with gross arterial atheroma and a family history of myocardial infarction but not of any hemorrhagic disorder.

Inhibition of tissue-type plasminogen activator by conditioned medium from cultured human and porcine vascular endothelial cells.

Conditioned serum-free medium both from confluent porcine aortic endothelial cells and from human venous and arterial umbilical cord endothelial cells will inhibit plasminogen activation by tissue-type plasminogen activator. Inhibitory activity in the conditioned medium increases with time, and depends upon protein synthesis. Also, the conditioned medium directly inhibits the amidolytic activity of tissue-type plasminogen activator.

Immunological characterization and possible origin of plasminogen activator in human tear fluid.

Human tear fluid has plasminogen activator activity. The type of plasminogen activator activity in unstimulated and stimulated tears was determined, using antibodies that specifically neutralize tissue plasminogen activator or urokinase. All plasminogen activator activity was tissue plasminogen activator-related in both types of tears.

A simple, sensitive spectrophotometric assay for extrinsic (tissue-type) plasminogen activator applicable to measurements in plasma.

An indirect spectrophotometric assay for extrinsic plasminogen activator has been devised, which is based on the parabolic assay of Drapier et al. (5). The system contains activator, plasminogen, the synthetic plasmin substrate H-D-Val-Leu-Lys-pNA (S-2251, Kabi) and a mixture of soluble fibrinogen fragments prepared by treatment of fibrinogen with cyanogen bromide.

Activation of plasminogen by tissue activator is increased specifically in the presence of certain soluble fibrin(ogen) fragments.

Tissue activator-mediated plasminogen activation is potentiated both by fibrin and by some soluble fibrin(ogen) fragments. The potentiating effect of the different fragments decreases in the order fibrin monomer greater than D-dimer greater than Y greater than D EGTA greater than Dcate greater than X. Fibrinogen and the fragments Ecate, E EGTA and E fibrin have almost no effect.