coagulation mechanism
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2021 ◽  
Vol 10 (21) ◽  
pp. 4840
Author(s):  
Hideo Wada ◽  
Yuhuko Ichikawa ◽  
Minoru Ezaki ◽  
Takeshi Matsumoto ◽  
Yoshiki Yamashita ◽  
...  

Object: Although thrombin burst has attracted attention as a physiological coagulation mechanism, clinical evidence from a routine assay for it is scarce. This mechanism was therefore evaluated by a clot waveform analysis (CWA) to assess the thrombin time (TT). Material and Methods: The TT with a low concentration of thrombin was evaluated using a CWA. We evaluated the CWA-TT of plasma deficient in various clotting factors, calibration plasma, platelet-poor plasma (PPP), and platelet-rich plasma (PRP) obtained from healthy volunteers, patients with thrombocytopenia, and patients with malignant disease. Results: Although the TT-CWA of calibration plasma was able to be evaluated with 0.01 IU/mL of thrombin, that of FVIII-deficient plasma could not be evaluated. The peak time of CWA-TT was significantly longer, and the peak height significantly lower, in various deficient plasma, especially in FVIII-deficient plasma compared to calibration plasma. The second peak of the first derivative (1st DP-2) was detected in PPP from healthy volunteers, and was shorter and higher in PRP than in PPP. The 1st DP-2 was not detected in PPP from patients with thrombocytopenia, and the 1st DP-2 in PRP was significantly lower in patients with thrombocytopenia and significantly higher in patients with malignant disease than in healthy volunteers. Conclusion: The CWA-TT became abnormal in plasma deficient in various clotting factors, and was significantly affected by platelets, suggesting that the CWA-TT may be a useful test for hemostatic abnormalities.


Author(s):  
Vijayarani. A* ◽  

In this analysis, the efficacy of adding coagulants such as Phaseolus lunatus and Phaseolus vulgaris (polymers) to the coagulation process during the treatment of arsenic aqueous solution to extract the arsenic metal was investigated. Experiments were carried out to evaluate the output of Phaseolus lunatus and Phaseolus vulgaris, both individually and in combination with arsenic, using the standard Jar test protocol. P.lunatus and P.vulgaris were given doses ranging from 1 to 3 gm. For P.lunatus and P.vulgaris, the (optimal) removal efficiency for total arsenic in the aqueous solution was obtained at 2gm. With chemical affinity between arsenic and coagulants used in this process, the valence state of arsenic may affect removal efficiency during the chemical coagulation process. pH is discovered to be a significant factor that has a direct or indirect impact on results. By overcoming the isoelectric point, the complex formed by the interaction of the inorganic pollutant and organic coagulant may aid in the removal of arsenic at pH 9 and 8. P.lunatus and P.vulgaris had optimised arsenic initial concentrations of 57.1µg/L and 42.6µg/L, respectively. The coagulation mechanism is more prevalent in water treatment, as shown by the above findings.


2021 ◽  
Author(s):  
Yuanyuan Xia ◽  
Xinping Li ◽  
Yue Yuan ◽  
Jingshun Zhuang ◽  
Wenliang Wang

Abstract The preparation of cellulose beads has attracted more and more attention in the application of advanced green materials. To obtain uniform and controllable cellulose beads, the dissolving pulp was dissolved in NMMO, and the cellulose beads were regenerated in various coagulation baths (water, alcohol, acid, NMMO, etc.) by phase conversion method. Results show that the crystal form of regenerated cellulose changes from cellulose I to cellulose II. NMMO swelling cellulose beads present low crystallinity and low water holding capacity. The coagulation mechanism of cellulose beads was clarified by a laser confocal microscopy. It is found that the whole coagulation process was from outside to inside gradually. It is a green and facile method for preparing cellulose beads with different structures and properties, which can be widely used in biomedicine, energy storage materials, and protein chromatography.


LWT ◽  
2021 ◽  
pp. 112000
Author(s):  
Yuhao Lu ◽  
Zebang Cui ◽  
Xiangfei Guan ◽  
Junyuan Lin ◽  
Xuequn Zhong ◽  
...  

Author(s):  
Xinliang Liu ◽  
Hailiang Yin ◽  
Jian Zhao ◽  
Ziqi Guo ◽  
Zhen Liu ◽  
...  

Abstract Coagulation kinetics and floc properties are of great fundamental and practical importance in the field of water treatment. To investigate the performance of Fe(VI) and Fe(III) salt on particle coagulation, Malvern Mastersizer 2000 was employed to continuously and simultaneously monitor the kaolin floc size and structure change, and population balance modeling was used to investigate the coagulation mechanism. The results show dosage increase had positive effect on collision efficiency and floc strength and negative effect on restructure rate. Low shear rate resulted in higher collision efficiency and stronger floc. Low water temperature had a pronounced detrimental effect on coagulation kinetics. Temperature increase showed the most significant positive effect on collision efficiency, floc strength and restructure rate. The optimum pH zone for the coagulation was found to be between 6 and 8. Further pH increase lowered the collision efficiency and floc strength and increased the restructure rate. FeCl3 resulted in a larger ratio of the mass to volume of kaolin flocs (compactness) than those induced by ferrate.


Biosensors ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 113
Author(s):  
Marinos Louka ◽  
Efstathios Kaliviotis

Blood coagulation is a defense mechanism, which is activated in case of blood loss, due to vessel damage, or other injury. Pathological cases arise from malfunctions of the blood coagulation mechanism, and rapid growth of clots results in partially or even fully blocked blood vessel. The aim of this work is to characterize blood coagulation, by analyzing the time-dependent structural properties of whole blood, using an inexpensive design and robust processing approaches. The methods used in this work include brightfield microscopy and image processing techniques, applied on finger-prick blood samples. The blood samples were produced and directly utilized in custom-made glass microchannels. Color images were captured via a microscopy-camera setup for a period of 35 min, utilizing three different magnifications. Statistical information was extracted directly from the color components and the binary conversions of the images. The main advantage in the current work lies on a Boolean classification approach utilized on the binary data, which enabled to identify the interchange between specific structural elements of blood, namely the red blood cells, the plasma and the clotted regions, as a result of the clotting process. Coagulation indices produced included a bulk coagulation index, a plasma-reduction based index and a clot formation index. The results produced with the inexpensive design and the low computational complexity in the current approach, show good agreement with the literature, and a great potential for a robust characterization of blood coagulation.


Author(s):  
В.Ф. Киричук ◽  
А.Н. Иванов ◽  
О.В. Злобина ◽  
И.О. Бугаева ◽  
А.Ю. Каретникова ◽  
...  

Введение. Патологическое повышение активности свертывающей системы вызывает нарушение реологических свойствкрови, является фактором риска развития тромбоза крупных сосудов и возникновения ишемической болезни сердца, инфаркта миокарда, тромбофилии и ДВС-синдрома. Цель исследования: изучение влияния светового десинхроноза на функциональную активность коагуляционного механизма гемостаза в эксперименте. Материалы и методы. Экспериментальное исследование было выполнено на 36 нелинейных самцах белых крыс, разделенных на 3 группы: контрольную группу, не подвергавшуюся воздействию светового десинхроноза, и 2 опытных, находившихся в условиях искусственного освещения на протяжении 10 и 21 суток, соответственно. Состояние коагуляционного звена системы гемостаза оценивали по следующим показателям: активированное частичное тромбопластиновое время, протромбиновое время и концентрация фибриногена. Антикоагулянтную активность крови оценивали путем определения активности в плазме крови антитромбина III. Состояние фибринолитической системы оценивали по концентрации в плазме растворимых фибрин-мономерных комплексов и D-димеров. Для динамической оценки активности тромбина применяли тест генерации тромбина. Результаты. Установлено негативное влияние светового десинхроноза на состояние гемостаза. На 10-е сутки эксперимента выявлено компенсаторное повышение активности противосвертывающей и фибринолитической систем. Нахождение подопытных животных в условиях длительной световой депривации на протяжении 21 суток способствовало развитию стресса и сдвигу системы гемостаза в сторону гиперкоагуляции. Заключение. Результаты проведенного экспериментального исследования позволяют сделать вывод о возникновении стресс-реакции у подопытных животных под воздействием светового десинхроноза, а также о гиперкоагуляционных нарушениях равновесия в системе гемостаза, что создает предпосылки для формирования тромбинемии. Background. A pathological increasing of coagulation activity causes disorders of blood rheological properties, that is a risk factor for large vessels thrombosis and coronary heart disease, myocardial infarction, thrombophilia and disseminated intravascular coagulation. Objectives: to study the effect of light desynchronosis on the functional activity of hemostasis coagulation mechanism in experiment. Materials/Methods. The experimental study was carried out on 36 nonlinear male white rats, divided into 3 groups: a control group that was not exposed to light desynchronosis, and 2 experimental groups under artificial lighting for 10 and 21 days, respectively. Coagulation hemostasis was assessed by following parameters: activated partial thromboplastin time, prothrombin time, and fibrinogen content. Anticoagulant blood activity was assessed by antithrombin III activity. Plasma levels of soluble fibrin-monomeric complexes and D-dimers were used for fibrinolytic system assessment. The thrombin generation assay was used for thrombin activity assessment. Results. Light desynchronosis negatively impact hemostasis. On the 10th day of the experiment we revealed a compensatory increasing of anticoagulant and fibrinolytic activities. Exposure of experimental animals to prolonged light deprivation for 21 days caused stress development and hemostasis shift towards hypercoagulation. Conclusions. Light desynchronosis leads to stress reaction in experimental animals as well as to hypercoagulable hemostasis disorders that creates the preconditions for thrombinemia.


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Minoru Morita ◽  
Jingjing Yang ◽  
Zhongwei Jiang

To improve the performance of the ultrasonic device during the endovascular operation, a scissor-type ultrasonic catheter device with compound vibration was developed. The heat generated by friction between the target and the device affects its coagulation mechanism while the actuator contacts the tissue. The scissor-type ultrasonic catheter device proposed in this study is expected to improve heat generation performance because it has the action of rubbing the object when it is pushed by combined vibration. In addition, since it is constructed by simple notch processing, it can be miniaturized and can be expected to be introduced into catheters. However, the observation of ultrasonic vibration during frictional heating is difficult, which is an issue for device design. In this paper, a thermal-structure coupling analysis was done using the finite element method to calculate the heat generation efficiency and evaluate its coagulation performance.


Foods ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 154
Author(s):  
Marina Marinea ◽  
Ashling Ellis ◽  
Matt Golding ◽  
Simon M. Loveday

In this study, a model system of firm tofu (pressed gel) was prepared to study how the coagulation mechanism—acidification with glucono δ-lactone (GDL) or coagulation with magnesium sulphate (MgSO4)—affected the physical properties of the gels along with their in vitro proteolysis (or extent of proteolysis). The two types of gels were also fortified with 3.5 mM protocatechuic (PCA) and coumaric acid (CMA) to test whether they can be used as bioactive delivery systems. Texture analysis showed that all MgSO4-induced gels (fortified and control) had a higher hydration capacity and a weaker texture than the GDL-induced gels (p < 0.05). MgSO4 gels had almost double proteolysis percentages throughout the in vitro digestion and showed a significantly higher amino acid bioaccessibility than the GDL gels (essential amino acid bioaccessibility of 56% versus 31%; p < 0.05). Lastly, both gel matrices showed a similar phenolic acid release profile, on a percentage basis (~80% for PCA and ~100% for CMA). However, GDL gels delivered significantly higher masses of bioactives under simulated intestinal conditions because they could retain more of the bioactives in the gel after pressing. It was concluded that the coagulation mechanism affects both the macro- and microstructure of the soy protein pressed gels and as a result their protein digestibility. Both pressed gel matrices are promising delivery systems for bioactive phenolic acids.


2020 ◽  
Vol 14 (2) ◽  
pp. 108
Author(s):  
Hans Kristianto ◽  
Angelica Jennifer ◽  
Asaf Kleopas Sugih ◽  
Susiana Prasetyo

Nowadays, various studies related to utilization of biobased materials as natural coagulants have been explored. Based on the source, natural coagulants can be classified as animal, vegetable, or microbial based. Furthermore, based on the active ingredients, it can be classified as protein, polyphenols, and polysaccharides. Polysaccharides are abundant natural ingredients and are often found in plants or animals. In this study, we focused on polysaccharides, especially those from fruit waste, such as seeds and fruit peels. It is known that around 25-30% of the total weight of fruit is generally wasted, even though it contains phytochemicals and various active ingredients that can be utilized, especially as a natural coagulant. This review will focus on the use of pectin and starch from fruit waste as natural coagulants for water- wastewater treatment. Generally, pectin is commonly found in the skin of fruits as part of the cell wall structure, while starch is found in fruit seeds as food reserves. To be used as a natural coagulant, pectin or starch need to be extracted first. In particular, starch needs to be modified either physically or chemically. The coagulation mechanism of pectin and starch usually follows the interparticle bridging mechanism. The use of pectin and starch from fruit waste needs to be explored and further investigated, to substitute the use of chemical coagulants.Keywords: coagulation; fruit waste; natural coagulant; polysaccharidesA B S T R A KDewasa ini berbagai studi terkait pemanfaatan bahan alam sebagai koagulan alami telah banyak dieksplorasi. Berdasarkan sumbernya, koagulan alami dapat digolongkan berbasis hewani, nabati, maupun mikrobial, sementara berdasarkan bahan aktifnya dapat digolongkan sebagai protein, polifenol, dan polisakarida. Polisakarida merupakan bahan alam yang berlimpah dan seringkali dijumpai pada tumbuh-tumbuhan dan hewan. Pada kajian ini difokuskan pada polisakarida terutama yang berasal dari limbah buah-buahan yang tidak termanfaatkan, seperti biji dan kulit buah. Diketahui sekitar 25-30% dari total berat buah pada umumnya terbuang, padahal memiliki kandungan fitokimia dan berbagai bahan aktif yang dapat dimanfaatkan, salah satunya sebagai koagulan alami. Pada tinjauan ini akan difokuskan pada pemanfaatan pektin dan pati dari limbah buah-buahan sebagai koagulan alami untuk pengolahan air dan limbah cair. Secara umum pektin umum dijumpai pada bagian kulit buah-buahan sebagai bagian dari struktur dinding sel, sementara pati umum dijumpai pada biji buah-buahan sebagai cadangan makanan. Untuk dapat dimanfaatkan sebagai koagulan alami, pektin ataupun pati perlu diekstrak terlebih dahulu, dan pati secara khusus perlu dimodifikasi baik secara fisika maupun kimia. Secara umum mekanisme koagulasi oleh pektin dan pati mengikuti mekanisme interparticle bridging. Pemanfaatan pektin dan pati dari limbah buah-buahan perlu dieksplorasi dan diteliti lebih lanjut, agar dapat mensubstitusi penggunaan koagulan kimia secara komersial.Kata kunci: koagulasi; koagulan alami; limbah buah-buahan; polisakarida


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