Enzyme May Clot Blood

1962 ◽  
Vol 81 (17) ◽  
pp. 258
Keyword(s):  
Clot Blood

Clot-Blood Contrast in Fast Gradient-Echo Magnetic Resonance Imaging

1993 ◽  
Vol 28 (7) ◽  
pp. 586-593 ◽  
Author(s):  
Justin J Wu ◽  
James R. MacFall ◽  
H Dirk Sostman ◽  
Laurence W. Hedlung
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Resonance Imaging ◽  
Gradient Echo ◽  
Fast Gradient ◽  
Clot Blood

Blood Thinners: From Heparin to Plavix

2014 ◽  
Author(s):  
Jie Jack Li
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Blood Clot ◽  
White Blood Cells ◽  
Clotting Factor ◽  
Blood Protein ◽  
Body Parts ◽  
Heart Attacks ◽  
Blood Clots ◽  
Clot Blood

Three types of blood cells exist in the human body: red blood cells, white blood cells, and platelets, in addition to plasma, which takes up 55 percent of the blood’s volume. Red blood cells take up approximately 45 percent of the blood’s volume. They transport oxygen from the lungs to other body parts. White cells defend us against bacterial and viral invasions. Platelets (less than 1 percent of the blood), the third type of blood cells, are sticky little cell fragments that are involved in helping the blood clot, a process known as coagulation. Without platelets (even though they constitute less than 1 percent of blood), our blood would not be able to clot, and we would have uncontrolled bleeding. However, formation of blood clots is a double-edged sword. Clots are beneficial because they heal cuts and wounds; blood clots in the bloodstream are harmful because they block coronary arteries, constrict vital oxygen supplies, and cause heart attacks and strokes, more and more frequent modern maladies as the baby boomers get older. Whenever the body is cut or injured and blood comes into contact with cells outside the bloodstream, a tissue factor on these cells encounters a particular protein within the blood, which triggers the clotting process. In the same vein, a series of other blood factors then come into action and amplify one another to quickly form a jelly-like blood clot. Blood clots form when an enzyme called thrombin marshals fibrin (a blood protein) and platelets (tiny cells that circulate in the blood) to coagulate at the site of an injury. Individuals with no ability to clot have a genetic condition called hemophilia; such people are also known as “bleeders.” Queen Victoria was hemophilic, and she passed on her genes to her many heirs who ruled Europe for over a century. This is why hemophilia is sometimes known as the royal disease. Symptoms of hemophilia manifest only in male offspring. People with hemophilia must periodically administer a clotting factor to their blood to prevent constant bleeding.

scholarly journals P1364CATIONIC CELLULOSE BASED PAD STOPS BLEEDING WITHIN FIVE MINUTES AFTER HEMODIALYSIS

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Kazuhiko Shibata ◽  
Hirokazu Morita ◽  
Mitsutaka Ueda ◽  
Shigeru Nakai
Keyword(s):  
Adverse Effects ◽  
Hemodialysis Patients ◽  
Adhesive Tape ◽  
Clinical Use ◽  
Puncture Site ◽  
Intravascular Thrombosis ◽  
Activated Clotting Time ◽  
The Cost ◽  
Short Time ◽  
Clot Blood

Abstract Background and Aims In case of prolonged bleeding at the vascular access site after hemodialysis, a nurse must compress the bleeding site longer than usual. This situation causes the risk of intravascular thrombosis and consumes valuable time of both patients and staff. Therefore, the method that can surely stop bleeding from the puncture site in short time is desired. Nowadays, chitosan is considered as one of the strongest hemostatic substance. Nipro Corporation and Artisan-lab co.,Ltd found the cationic cellulose could clot blood faster than chitosan in the activated clotting time (ACT). After carefully examining its safety and efficacy, it was approved as medicine by the Japanese Ministry of Health, Labor and Welfare. Then, a trial to verify its clinical efficacy as a hemostat was conducted in the Yokohama Minami Clinic. Method 150 hemodialysis patients treated at the Yokohama Minami Clinic excluding those using catheters or having with good hemostasis were selected as candidates for this study. 127 patients (64 men and 63 women) among them agreed to participate in this study after our explanation. 547 times of 5 minutes’ compression hemostasis were performed to the patients using cationic-cellulose pads for hemostasis from December 29th in 2019 to January 3rd in 2020. We checked the bleeding evidence of the puncture sites at the both timing of immediately after relieving their compression and the start of the following session. At their following session starting, we also checked the existence of adverse effects at their puncture sites, such as contact dermatitis or infection. Results Five of 547 cases (0.9%) had bleeding immediately after their compression relieving, and they needed to prolong their compression (the average of prolongation time was 3.0 minutes). But the other 542 cases (99.1%) successfully stopped bleeding within 5 minutes. All cases except two cases with redness at the adhesive tape attached site did not have any adverse effects such as redness, itching or pain of their hemostatic pad attached sites, including one case who forgot to remove his hemostatic pad until 48 hours later. The nurses could reduce their efforts to check the patients’ hemostasis and work smoother than usual, throughout this study period. Discussion In most cases of this study, the cationic-cellulose pad could stop bleeding within 5 minutes without any adverse effects. This result suggests that this material has sufficient performance for clinical use. The cationic-cellulose used for the hemostatic pads in this study had already had high enough quality for clinical use and it was produced by Kao Corporation. At present, clinically available strong hemostatic agents are too expensive to be applied for every patient. But the cost to get the cationic-cellulose to make hemostatic pads may be reduced enough low to be distributed to all hemodialysis patients because this material is mass-produced for hairdressing agent. Conclusion The cationic cellulose pad can save precious time and efforts of both patients and staff through its quick hemostasis. Figure The cationic cellulose pad

scholarly journals PHYSICOCHEMICAL PROPERTIES OF THE PROTEOLYTIC ENZYME FROM THE LATEX OF THE MILKWEED, ASCLEPIAS SPECIOSA TORR. SOME COMPARISONS WITH OTHER PROTEASES

1940 ◽  
Vol 23 (3) ◽  
pp. 275-288 ◽  
Author(s):  
Theodore Winnick ◽  
Alva R. Davis ◽  
David M. Greenberg
Keyword(s):  
Physicochemical Properties ◽  
Proteolytic Activity ◽  
Proteolytic Enzyme ◽  
Chemical Diffusion ◽  
Urea Solution ◽  
Optimum Temperature ◽  
Asclepias Speciosa ◽  
Clot Blood

1. A study has been made of the properties of a hitherto unreported proteolytic enzyme from the latex of the milkweed, Asclepias speciosa. The new protease has been named asclepain by the authors. 2. The results of chemical, diffusion, and denaturation tests indicate that asclepain is a protein. 3. Like papain, asclepain dots milk and digests most proteins, particularly if they are dissolved in concentrated urea solution. Unlike papain, asclepain did not clot blood. 4. The activation and inhibition phenomena of asclepain resemble those of papain, and seem best explained on the assumption that free sulfhydryl in the enzyme is necessary for proteolytic activity. The sulfhydryl of asclepain appears more labile than that of papain. 5. The measurement of pH-activity curves of asclepain on casein, ovalbumin, hemoglobin, edestin, and ovovitellin showed no definite digestion maxima for most of the undenatured proteins, while in urea solution there were well defined maxima near pH 7.0. Native hemoglobin and ovovitellin were especially undigestible, while native casein was rapidly attacked. 6. Temperature-activity curves were determined for asclepain on hemoglobin, casein, and milk solutions. The optimum temperature was shown to increase with decreasing time of digestion.

MO781THE CATIONIC CELLULOSE BASED PAD REDUCE THE HEMOSTATIC TIME AFTER HEMODIALYSIS

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Kazuhiko Shibata ◽  
Shigeru Nakai ◽  
Yusuke Kobayashi ◽  
Kiyoshi Ozawa ◽  
Koichi Tamura
Keyword(s):  
Adverse Effects ◽  
Hemodialysis Patients ◽  
Clotting Time ◽  
Access Site ◽  
Hemostatic Agents ◽  
Intravascular Thrombosis ◽  
Activated Clotting Time ◽  
The Cost ◽  
Clot Blood ◽  
Hemodialysis Machine

Abstract Background and Aims In case of prolonged bleeding at the vascular access site after hemodialysis, a nurse must compress the bleeding site longer than usual. This situation causes the risk of intravascular thrombosis and consumes valuable time of both patients and staff. Therefore, effective hemostatic agents are desired. Nowadays, chitosan is considered as one of the strongest hemostatic substance. Nipro Corporation and Artisan-lab co., Ltd found the cationic cellulose could clot blood faster than chitosan in the activated clotting time (Figure). After carefully examining its safety and efficacy, it was approved as medicine by the Japanese Ministry of Health, Labor and Welfare. Then, a trial to verify its clinical efficacy as a hemostat was conducted in the Toshin Clinic. In our clinic, the timer is set on the hemodialysis machine after the needles are removed and pressure is started after hemodialysis. We examined how long the timer should be set to be able to sufficiently stop bleeding in case cationic-cellulose pads are used. Method Of the 150 hemodialysis patients treated at the Toshin clinic; patients who agreed to this trial were enrolled. We set a timer for 5 minutes initially using cationic-cellulose pads for hemostasis, and was shortened in the next trial by 1 minute if the bleeding had been stopped. If the patient did not consent, the timer was not shortened further. from April 15th to December 31st in 2020. We checked the bleeding evidence of the puncture sites at the timing of immediately after relieving their compression. At their following hemodialysis session, we also checked the existence of adverse effects at their puncture sites, such as contact dermatitis or infection. Results Ten patients (9 men and 1 woman, Age 58.5y ±13.1) agreed to participate in this study. In the case of stable hemostasis, we continued to shorten the time by 1 minute each time, and added 1 minute in case of bleeding. After searching for the shortest time to achieve stable hemostasis, we confirmed hemostasis an average of 14.2 times in all cases. The average time to set for the timer was 3.0 ± 0.94 minutes (2-5 minutes). Two patients refused to shorten the time set for the timer, the hemostasis time were 5 and 4minutes respectively. The hemostasis time in all the other cases was equal or less than 3 minutes. In one case, the hemostasis time was reduced to 3 minutes with a cationic cellulose pad, compared to 30 minutes with The Neoplaster hemostatic pad (Nipro Corporation) which is made with the carboxymethyl cellulose. Of the 142 case compressions performed, 1 case resulted in bleeding and required 2 minutes of additional compressions. All cases did not have any adverse effects such as redness, itching or pain of their hemostatic pad attached sites. Discussion This study showed that the average time to set for the timer, when using cationic cellulose pad was 3 minutes on average, without any adverse effects. Cationic cellulose pads can stop bleeding safely, quickly and stably. At present, clinically available strong hemostatic agents are too expensive to be applied for many patients. But the cost to get the cationic-cellulose to make hemostatic pads may be reduced enough to be distributed to many hemodialysis patients because this material is mass-produced for hair conditioner, shampoo, and toothpaste. Conclusion The average time set for the timer was estimated around 3 minutes using the cationic cellulose pad. The cationic cellulose pad can save precious time and efforts of both patients and staff through its quick hemostasis.

scholarly journals CRYSTALLINE CHYMO-TRYPSIN AND CHYMO-TRYPSINOGEN

1935 ◽  
Vol 18 (4) ◽  
pp. 433-458 ◽  
Author(s):  
M. Kunitz ◽  
John H. Northrop
Keyword(s):  
Chemical Properties ◽  
Intramolecular Rearrangement ◽  
Milk Clotting ◽  
Optimum Ph ◽  
Primary Amino ◽  
Clot Blood ◽  
Physical And Chemical ◽  
Hydrolysis Of ◽  
Rate Of Activation ◽  
And Chemical Properties

A new crystalline protein, chymo-trypsinogen, has been isolated from acid extracts of fresh cattle pancreas. This protein is not an enzyme but is transformed by minute amounts of trypsin into an active proteolytic enzyme called chymo-trypsin. The chymo-trypsin has also been obtained in crystalline form. The chymo-trypsinogen cannot be activated by enterokinase, pepsin, inactive trypsin, or calcium chloride. There is an extremely slow spontaneous activation upon standing in solution. The activation of chymo-trypsinogen by trypsin follows the course of a monomolecular reaction the velocity constant of which is proportional to the trypsin concentration and independent of the chymotrypsinogen concentration. The rate of activation is a maximum at pH 7.0–8.0. Activation is accompanied by an increase of six primary amino groups per mole but no split products could be found, indicating that the activation consists in an intramolecular rearrangement. There is a slight change in optical activity but no change in molecular weight. The physical and chemical properties of both proteins are constant through a series of fractional crystallizations. The activity of chymo-trypsin decreases in proportion to the destruction of the native protein by pepsin digestion or denaturation by heat or acid. Chymo-trypsin has powerful milk-clotting power but does not clot blood plasma and differs qualitatively in this respect from the crystalline trypsin previously reported. It hydrolyzes sturin, casein, gelatin, and hemoglobin more slowly than does crystalline trypsin but the hydrolysis of casein is carried much further. The hydrolysis takes place at different linkages from those attacked by trypsin. The optimum pH for the digestion of casein is about 8.0–9.0. It does not hydrolyze any of a series of dipeptides or polypeptides tested. Several chemical and physical properties of both proteins have been determined.

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