scholarly journals EFFECT OF BLOOD THROMBOKINASE, AS INFLUENCED BY SOY BEAN TRYPSIN INHIBITOR; ULTRACENTRIFUGATION, AND ACCESSORY FACTORS

1955 ◽  
Vol 38 (6) ◽  
pp. 757-769 ◽  
Author(s):  
J. H. Milstone
Keyword(s):  
Trypsin Inhibitor ◽  
Calcium Ions ◽  
Barium Carbonate ◽  
The Other ◽  
Potential Source ◽  
Accessory Factor ◽  
Bean Trypsin Inhibitor ◽  
Ionic Calcium ◽  
Accessory Factors ◽  
Almost All

1. Crystallized soy bean trypsin inhibitor, at a concentration of 100 µg./ml., suppressed the production of thrombin from a mixture of prothrombin and blood thrombokinase. The experiment was performed in the presence of 0.011 M oxalate, in order to minimize the possibility of participation by accessory factors which require ionic calcium. The results are in accord with the view that thrombokinase is a trypsin-like enzyme. 2. When a solution of blood thrombokinase was centrifuged at 85,000 g for 120 minutes, almost all the activity remained in the supernate. This supernate activated the supernate from a prothrombin solution which had been similarly centrifuged. The activation of prothrombin by thrombokinase can proceed in the absence of material completely sedimentable in 120 minutes at 85,000 g. 3. An "accelerator" reagent was prepared by treating bovine serum with barium carbonate, and then passing the serum through a column of diatomaceous earth. This "accelerator" was used together with prothrombin, blood thrombokinase, Howell's cephalin, and calcium chloride to compose a five-reagent thrombin-producing system. In this system, no thrombin was produced without thrombokinase. On the other hand, thrombin was produced from prothrombin and thrombokinase, even when all the other reagents were omitted. When calcium was omitted, thrombokinase was able to function; but cephalin and the "accelerator" reagent were ineffective. 4. Quantitative tests indicated that the "accelerator" reagent exerted an effect distinct from those of thrombokinase and cephalin. However, it is not certain whether the "accelerator" reagent functioned as an accessory factor, as a potential source of more thrombokinase, or both. In the experiments reported, thrombokinase was primary to, or necessary for, the effect of "accelerator." 5. The effectiveness of thrombokinase was multiplied a hundred times or more, when complemented by calcium, cephalin, and "accelerator" reagent. Ionic calcium was a necessary component of this complementing system. This may help to explain why removal of calcium ions keeps blood fluid, even though thrombokinase, by itself, is little influenced either by calcium ions or by oxalate.

scholarly journals Ligand binding, conformational change and plasma elimination of human, mouse and rat α-macroglobulin proteinase inhibitors

1983 ◽  
Vol 209 (1) ◽  
pp. 99-105 ◽  
Author(s):  
S L Gonias ◽  
A E Balber ◽  
W J Hubbard ◽  
S V Pizzo
Keyword(s):  
Ligand Binding ◽  
Conformational Change ◽  
Trypsin Inhibitor ◽  
Proteinase Inhibitor ◽  
Proteinase Inhibitors ◽  
Soya Bean ◽  
The Other ◽  
Complex Reaction ◽  
Bean Trypsin Inhibitor ◽  
Esterolytic Activity

Rat alpha 1-macroglobulin (alpha 1M), rat alpha 2-macroglobulin (alpha 2M) migrated as single bands on non-denaturing gels when purified by the methods described. All three proteins demonstrated increased mobility after reaction with trypsin. A single saturable pathway rapidly cleared complexes of trypsin and the alpha-macroglobulins of mouse, rat and human from the circulation of mice. None of the native alpha-macroglobulins competed for clearance with the trypsin complexes. [14C]Methylamine incorporation was 4.1, 3.9, 2.6 and 3.2 mol/mol of proteinase inhibitor for human alpha 2M, rat alpha 1M, rat alpha 2M and mouse alpha 2M, respectively. Only rat alpha 2M, the acute-phase alpha-macroglobulin studied, showed no evidence of conformational change when subjected to electrophoresis after reaction with methylamine. The clearance of rat alpha 2M-methylamine was comparable with that of the native molecule. The other alpha-macroglobulin-methylamine complexes cleared faster than the inhibitors that had not reacted. Rat alpha 2M and rat alpha 2M-methylamine bound equivalent quantities of 1251-labelled trypsin (1.01 and 0.96 mol/mol respectively). The soya-bean trypsin inhibitor-resistant esterolytic activity of trypsin bound to rat alpha 2M-methylamine was approx. 90% suppressed compared with proteinase bound to native rat alpha 2M. This suppression was not due to a change in the affinity of soya-bean trypsin inhibitor for the complex. Reaction of rat alpha 2M-methylamine with trypsin resulted in a ‘slow’ to ‘fast’ electrophoretic conversion of the proteinase inhibitor, and exposure of the signal on the alpha 2M that causes the complex to clear from the murine circulation.

Factor X Activation by washed human platelets

1979 ◽  
Author(s):  
E van Wijk ◽  
L Kahlé ◽  
J ten Cate
Keyword(s):  
Human Factors ◽  
Trypsin Inhibitor ◽  
Calcium Ions ◽  
Factor Xa ◽  
Human Platelets ◽  
Soybean Trypsin Inhibitor ◽  
Thrombin Inhibitor ◽  
Chromogenic Substrate ◽  
Factor X ◽  
Factor X Activation

In a system of washed human platelets, Ca2+and purified human factors X anc II, a sufficient amount of thrombin is generated in about 10 minutes to aggregate the platelets. This thrombin is formed through the activation of FX by the platelets. In a system with either FX or FII present, no aggregation occurs. In addition no aggregation is observed when hirudin, a specific thrombin inhibitor, or when soybean trypsin inhibitor, which inhibits factor Xa, are added to the mixture. The formation of factor Xa can be monitored indirectly through the generation of thrombin, in the presence of an excess of prothrombin, using a thrombin sensitive chromogenic substrate. When washed platelets are incubated with FX alone for 10 minutes, no aggregation occurs and after the addition of prothrombin aggregation starts within 6 minutes. These findings confirm that washed platelets possess a factor X activating property. The generation of FXa proceeds in the absence of added Ca2+, whereas in the presence of Ca2+factor Xa activity reaches a maximum in 3 minutes, whereafter the activity progressively decreases. This may be due to the binding of Xa to the platelets in the presence of calcium ions.

Starość w nauczaniu św. Bazylego Wielkiego

Vox Patrum ◽  
2011 ◽  
Vol 56 ◽  
pp. 339-348
Author(s):  
Bogdan Czyżewski
Keyword(s):  
Old Age ◽  
Spiritual Maturity ◽  
The Other ◽  
Interesting Aspect ◽  
Other Hand ◽  
Physical Suffering ◽  
Way Of Thinking ◽  
Almost All

Although St. Basil did not live 50 years, the topic of the old age appears in his works quite often. On the other hand, it is clear that Basil does not discuss this issue in one par­ticular work or in the longer argumentation. The fragmentary statements about old age can be found in almost all his works, but most of them can be found in the correspondence of Basil. In this paper we present the most important ad the most interesting aspect of teach­ing of Basil the Great. As these certificates show that the bishop of Caesarea looked at the old age maturely, rationally estimated passage of time, which very often makes a man different. He experienced it, for example as a spiritual and physical suffering, which often were connected with his person. He saw a lot of aspect of the old age, especially its advan­tages – spiritual maturity and wisdom. What is more, he pointed also to passage of time, which leads a man to eternity, which should be prepared to, regardless how old he is. In his opinion fear is not seen opinions of St. Basil present really Christian way of thinking, well-balanced and calm.

Activation of latent collagenase from polymorphonuclear leukocytes by cathepsin G

1979 ◽  
Vol 44 (10) ◽  
pp. 3177-3182 ◽  
Author(s):  
Mária Stančíková ◽  
Karel Trnavský
Keyword(s):  
Affinity Chromatography ◽  
Trypsin Inhibitor ◽  
Polymorphonuclear Leukocytes ◽  
Soya Bean ◽  
Cathepsin G ◽  
Sepharose Column ◽  
Bean Trypsin Inhibitor ◽  
Human Polymorphonuclear Leukocytes

Cathepsin G was isolated from human polymorphonuclear leukocytes and purified by affinity chromatography on Antilysin-Sepharose column. Purified enzyme activated later collagenase isolated from leukocytes. Activation at 36°C was maximal after 30 min incubation. Inhibitors of cathepsin G - soya-bean trypsin inhibitor, diisopropyl phosphofluoridate and Antilysin were active in inhibiting the activation of latent collagenase by cathepsin G.

scholarly journals THE TERMINAL GROUPS OF THE SOY BEAN TRYPSIN INHIBITOR

1955 ◽  
Vol 212 (2) ◽  
pp. 507-514
Author(s):  
Earl W. Davie ◽  
Hans Neurath
Keyword(s):  
Trypsin Inhibitor ◽  
Bean Trypsin Inhibitor

scholarly journals Raw soya-bean flour increases cholecystokinin release in man

1987 ◽  
Vol 58 (2) ◽  
pp. 175-179 ◽  
Author(s):  
John Calam ◽  
Joanna C. Bojarski ◽  
Caroline J. Springer
Keyword(s):  
Heat Treatment ◽  
Trypsin Inhibitor ◽  
Soya Bean ◽  
The Other ◽  
Oral Ingestion ◽  
Pancreatic Acini ◽  
Bean Flour ◽  
Heat Treated ◽  
Releasing Effect ◽  
Cck Release

1. The aim of the present study was to determine whether oral ingestion of raw soya-bean flour, which contains trypsin inhibitors, alters the release of cholecystokinin (CCK) in man.2. Eleven healthy volunteers ate two mixed meals: one with raw soya-bean flour and the other with soya-bean flour that had been heat-treated. The two flours inhibited 34 and 3 mg trypsin/g flour respectively.3. CCK was measured in plasma using a bioassay based on the release of amylase (EC 3.2.1.1) from dispersed rat pancreatic acini.4. The peak CCK response was 168 (SE 8.1) pmol/l with raw soya-bean flour but 4.9 (SE 2.8) pmol/l with heat-treated flour (P < 0.05).5. We conclude that ingestion of raw soya-bean flour increases CCK release in man and that heat treatment which reduces the trypsin inhibitor content of the flour also diminishes its CCK-releasing effect.

Descriptions of the larvae of four species of Procladius from Great Slave Lake (Chironomidae:Diptera)

1978 ◽  
Vol 56 (9) ◽  
pp. 2055-2057 ◽  
Author(s):  
J. W. Moore ◽  
I. A. Moore
Keyword(s):  
Antennal Segment ◽  
The Other ◽  
Large Size ◽  
Great Slave Lake ◽  
Palpal Segment ◽  
Almost All

Descriptions of larvae of Procladius denticulatus, Procladius culiciformis, Procladius freemani, and Procladius bellus collected from Yellowknife Bay (lat., 62°25′; long., 114°20′) are given. Procladius denticulatus was separated from the other species by its large size, a character which always proved distinctive. Procladius culiciformis and P. freemani were separated from one another through several measurements including those of the basal antennal segment and the basal palpal segment. Almost all characters of the head were useful in distinguishing the much smaller P. bellus from the other species.

scholarly journals Mirolase, a novel subtilisin-like serine protease from the periodontopathogen Tannerella forsythia

2015 ◽  
Vol 396 (3) ◽  
pp. 261-275 ◽  
Author(s):  
Miroslaw Ksiazek ◽  
Abdulkarim Y. Karim ◽  
Danuta Bryzek ◽  
Jan J. Enghild ◽  
Ida B. Thøgersen ◽  
...  
Keyword(s):  
Serine Protease ◽  
Calcium Ions ◽  
Enzyme Stability ◽  
Amidolytic Activity ◽  
Tannerella Forsythia ◽  
Calcium Dependent ◽  
Genes Encoding ◽  
Mature Enzyme ◽  
Almost All ◽  
Unique Mechanism

Abstract The genome of Tannerella forsythia, an etiological factor of chronic periodontitis, contains several genes encoding putative proteases. Here, we characterized a subtilisin-like serine protease of T. forsythia referred to as mirolase. Recombinant full-length latent promirolase [85 kDa, without its signal peptide (SP)] processed itself through sequential autoproteolytic cleavages into a mature enzyme of 40 kDa. Mirolase latency was driven by the N-terminal prodomain (NTP). In stark contrast to almost all known subtilases, the cleaved NTP remained non-covalently associated with mirolase, inhibiting its proteolytic, but not amidolytic, activity. Full activity was observed only after the NTP was gradually, and fully, degraded. Both activity and processing was absolutely dependent on calcium ions, which were also essential for enzyme stability. As a consequence, both serine protease inhibitors and calcium ions chelators inhibited mirolase activity. Activity assays using an array of chromogenic substrates revealed that mirolase specificity is driven not only by the substrate-binding subsite S1, but also by other subsites. Taken together, mirolase is a calcium-dependent serine protease of the S8 family with the unique mechanism of activation that may contribute to T. forsythia pathogenicity by degradation of fibrinogen, hemoglobin, and the antimicrobial peptide LL-37.

scholarly journals Geographical matching of volatile signals and pollinator olfactory responses in a cycad brood-site mutualism

2015 ◽  
Vol 282 (1816) ◽  
pp. 20152053 ◽  
Author(s):  
Terence N. Suinyuy ◽  
John S. Donaldson ◽  
Steven D. Johnson
Keyword(s):  
Choice Experiments ◽  
Local Region ◽  
The Other ◽  
Beetle Species ◽  
Olfactory Preference ◽  
Olfactory Responses ◽  
Volatile Emissions ◽  
Extant Species ◽  
Insect Pollinators ◽  
Almost All

Brood-site mutualisms represent extreme levels of reciprocal specialization between plants and insect pollinators, raising questions about whether these mutualisms are mediated by volatile signals and whether these signals and insect responses to them covary geographically in a manner expected from coevolution. Cycads are an ancient plant lineage in which almost all extant species are pollinated through brood-site mutualisms with insects. We investigated whether volatile emissions and insect olfactory responses are matched across the distribution range of the African cycad Encephalartos villosus . This cycad species is pollinated by the same beetle species across its distribution, but cone volatile emissions are dominated by alkenes in northern populations, and by monoterpenes and a pyrazine compound in southern populations. In reciprocal choice experiments, insects chose the scent of cones from the local region over that of cones from the other region. Antennae of beetles from northern populations responded mainly to alkenes, while those of beetles from southern populations responded mainly to pyrazine. In bioassay experiments, beetles were most strongly attracted to alkenes in northern populations and to the pyrazine compound in southern populations. Geographical matching of cone volatiles and pollinator olfactory preference is consistent with coevolution in this specialized mutualism.

Nitrendipine blocks high potassium contractures but not twitches in rat skeletal muscle

1988 ◽  
Vol 66 (9) ◽  
pp. 1210-1213 ◽  
Author(s):  
G. B. Frank ◽  
L. Konya ◽  
T. Subrahmanyam Sudha
Keyword(s):  
Skeletal Muscle ◽  
Calcium Ions ◽  
Calcium Uptake ◽  
Channel Blocker ◽  
Mechanical Response ◽  
Extracellular Calcium ◽  
The Other ◽  
Rat Skeletal Muscle ◽  
Potassium Depolarization ◽  
High Potassium

The effects of the organic calcium channel blocker nitrendipine was tested on electrically evoked twitches and on potassium depolarization-induced contractures of rat lumbricalis muscles. Nitrendipine (10−7 to 5 × 10−5 M) blocked only the potassium contractures. It was concluded that blocking calcium uptake through the slow voltage-senstitive calcium channels during potassium depolarization blocks the mechanical response of the muscle. Thus extracellular calcium ions are required for the excitation–contraction (E–C) coupling during depolarization contractures. On the other hand, electrically evoked twitches were not affected by nitrendipine; therefore, extracellular calcium ions entering via the slow voltage-sensitive channels are not required for E–C coupling during the twitch.

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