scholarly journals Modification of Arabinogalactan Isolated from Larix sibirica Ledeb. into Sulfated Derivatives with the Controlled Molecular Weights

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5364
Author(s):  
Yuriy N. Malyar ◽  
Natalia Yu. Vasilyeva ◽  
Aleksandr S. Kazachenko ◽  
Valentina S. Borovkova ◽  
Andrei M. Skripnikov ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Numerical Optimization ◽  
Sulfamic Acid ◽  
Larix Sibirica ◽  
Process Time ◽  
Reaction Products ◽  
Molecular Weights ◽  
High Sulfur Content ◽  
Natural Polysaccharide ◽  
First Time

The process of sulfation of arabinogalactan—a natural polysaccharide from Larix sibirica Ledeb.—with sulfamic acid in 1,4-dioxane using different activators has been studied for the first time. The dynamics of the molecular weight of sulfated arabinogalactan upon variation in the temperature and time of sulfation of arabinogalactan with sulfamic acid in 1,4-dioxane has been investigated. It has been found that, as the sulfation time increases from 10 to 90 min, the molecular weights of the reaction products grow due to the introduction of sulfate groups without significant destruction of the initial polymer and sulfation products. Sulfation at 95 °C for 20 min yields the products with a higher molecular weight than in the case of sulfation at 85 °C, which is related to an increase in the sulfation rate; however, during the further process occurring under these conditions, sulfation is accompanied by the destruction and the molecular weight of the sulfated polymer decreases. The numerical optimization of arabinogalactan sulfation process has been performed. It has been shown that the optimal parameters for obtaining a product with a high sulfur content are a sulfamic acid amount of 20 mmol per 1 g of arabinogalactan, a process temperature of 85 °C, and a process time of 2.5 h.

scholarly journals Gelatinases in Boar Seminal Plasma and Their Relation to Semen Indicators

2010 ◽  
Vol 79 (3) ◽  
pp. 491-496 ◽  
Author(s):  
Maja Zakošek Pipan ◽  
Marjan Kosec ◽  
Janko Mrkun ◽  
Petra Zrimšek
Keyword(s):  
Molecular Weight ◽  
Enzyme Activity ◽  
Seminal Plasma ◽  
Animal Species ◽  
Sperm Concentration ◽  
Gelatin Zymography ◽  
Motile Sperm ◽  
Molecular Weights ◽  
Simultaneous Identification ◽  
First Time

Matrix metalloproteinases were detected in reproductive tissues and seminal plasma of various animal species. The aim of this study was to determine for the first time the presence of gelatinases and metalloproteases in boar seminal plasma and to correlate the results with semen indicators. Gelatin zymography was used for simultaneous identification and measurement of gelatinase enzyme activity associated with their molecular weights. Several gelatinase forms were identified in seminal plasma of boars. Those that were stimulated by CaCl2 and inhibited by EDTA and phenanthroline were considered as metalloproteases. Negative correlation between semen indicators (sperm index, sperm concentration and concentration of progressive motile sperm) and the concentrations of metalloprotease at 78 kDa and 66 kDa means that higher values of semen indicators correlate with lower concentrations of these metaloproteases in seminal plasma. Gelatinases with molecular weight of 225, 78 and 66 kDa correlated with higher levels of acrosome damage. Samples with sperm index above 110 M/ml contained gelatinases of significantly lower band intensities at 78 and 66 kDa compared to samples with SI less than 110 M/ml. Bands with 225, 78 and 66 kDa are suggested to belong to a dimer of MMP-9, proMMP-2 and mature MMP-2.

scholarly journals The preparation of activated Factor X and its action on prothrombin

1973 ◽  
Vol 131 (4) ◽  
pp. 791-797 ◽  
Author(s):  
Jolyon Jesty ◽  
M. Peter Esnouf
Keyword(s):  
Molecular Weight ◽  
Factor Xa ◽  
Mean Value ◽  
Factor V ◽  
Factor X ◽  
Reaction Products ◽  
Molecular Weights ◽  
Russell’S Viper ◽  
Bovine Factor

The preparation of activated Factor X from reaction mixtures of bovine Factor X and Russell's-viper venom is described. The molecular weight of purified protein varies about a mean value of 40000; this variation is the result of at least two forms of Factor Xa. The action of activated Factor X, together with purified Factor V, was studied on purified prothrombin and the reaction products were isolated. In addition to thrombin, two other polypeptides with molecular weights of 16000 and 19500 were recovered.

Green-solvent processable semiconducting polymers applicable in additive-free perovskite and polymer solar cells: molecular weights, photovoltaic performance, and thermal stability

2018 ◽  
Vol 6 (14) ◽  
pp. 5538-5543 ◽  
Author(s):  
Junwoo Lee ◽  
Tack Ho Lee ◽  
Mahdi Malekshahi Byranvand ◽  
Kyoungwon Choi ◽  
Hong Il Kim ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Solar Cells ◽  
Polymer Solar Cells ◽  
Photovoltaic Performance ◽  
Semiconducting Polymers ◽  
Green Solvent ◽  
Molecular Weights ◽  
First Time

In this study, we demonstrated the effects of the molecular weight (MW) of a green processable polymer (asy-PBTBDT) on its photovoltaic performance and thermal stability for the first time.

Investigation by HPLC of the Catabolism of Recombinant Tissue Plasminogen Activator in the Rat

1988 ◽  
Vol 60 (01) ◽  
pp. 107-112 ◽  
Author(s):  
Roy Harris ◽  
Louis Garcia Frade ◽  
Lesley J Creighton ◽  
Paul S Gascoine ◽  
Maher M Alexandroni ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Half Life ◽  
Recombinant Tissue Plasminogen Activator ◽  
Rat Plasma ◽  
High Molecular Weight Complex ◽  
Molecular Weights ◽  
Major Activity ◽  
Tissue Plasminogen

SummaryThe catabolism of recombinant tissue plasminogen activator (rt-PA) was investigated after injection of radiolabelled material into rats. Both Iodogen and Chloramine T iodination procedures yielded similar biological activity loss in the resultant labelled rt-PA and had half lives in the rat circulation of 1 and 3 min respectively. Complex formation of rt-PA was investigated by HPLC gel exclusion (TSK G3000 SW) fractionation of rat plasma samples taken 1-2 min after 125I-rt-PA injection. A series of radiolabelled complexes of varying molecular weights were found. However, 60% of the counts were associated with a single large molecular weight complex (350–500 kDa) which was undetectable by immunologically based assays (ELISA and BIA) and showed only low activity with a functional promoter-type t-PA assay. Two major activity peaks in the HPLC fractions were associated with Tree t-PA and a complex having a molecular weight of ̴ 180 kDa. HPLC fractionation to produce these three peaks at various timed intervals after injection of 125I-rt-PA showed each to have a similar initial rate half life in the rat circulation of 4-5 min. The function of these complexes as yet is unclear but since a high proportion of rt-PA is associated with a high molecular weight complex with a short half life in the rat, we suggest that the formation of this complex may be a mechanism by which t-PA activity is initially regulated and finally cleared from the rat circulation.

Permeability Enhancing and Chemotactic Activities of Lower Molecular Weight Degradation Products of Human Fibrinogen

1981 ◽  
Vol 45 (01) ◽  
pp. 090-094 ◽  
Author(s):  
Katsuo Sueishi ◽  
Shigeru Nanno ◽  
Kenzo Tanaka
Keyword(s):  
Molecular Weight ◽  
Degradation Products ◽  
Electron Microscopic Observation ◽  
Chemotactic Activity ◽  
Lower Molecular Weight ◽  
Electron Microscopic ◽  
Human Fibrinogen ◽  
Rabbit Skin ◽  
Molecular Weights ◽  
Active Fragments

SummaryFibrinogen degradation products were investigated for leukocyte chemotactic activity and for enhancement of vascular permeability. Both activities increased progressively with plasmin digestion of fibrinogen. Active fragments were partially purified from 24 hr-plasmin digests. Molecular weights of the permeability increasing and chemotactic activity fractions were 25,000-15,000 and 25,000 respectively. Both fractions had much higher activities than the fragment X, Y, D or E. Electron microscopic observation of the small blood vessels in rabbit skin correlated increased permeability with the formation of characteristic gaps between adjoining endothelial cells and their contraction.These findings suggest that lower molecular weight degradation products of fibrinogen may be influential in contributing to granulocytic infiltration and enhanced permeability in lesions characterized by deposits of fibrin and/or fibrinogen.

Toxicity of Heparinoids, with Special Reference to the Precipitation of Fibrinogen

1964 ◽  
Vol 12 (01) ◽  
pp. 232-261 ◽  
Author(s):  
S Sasaki ◽  
T Takemoto ◽  
S Oka
Keyword(s):  
Molecular Weight ◽  
Dextran Sulfate ◽  
Anticoagulant Activity ◽  
Molecular Structures ◽  
Severe Reaction ◽  
Clinical Use ◽  
Molecular Weights ◽  
Close Relationship

SummaryTo demonstrate whether the intravascular precipitation of fibrinogen is responsible for the toxicity of heparinoid, the relation between the toxicity of heparinoid in vivo and the precipitation of fibrinogen in vitro was investigated, using dextran sulfate of various molecular weights and various heparinoids.1. There are close relationships between the molecular weight of dextran sulfate, its toxicity, and the quantity of fibrinogen precipitated.2. The close relationship between the toxicity and the precipitation of fibrinogen found for dextran sulfate holds good for other heparinoids regardless of their molecular structures.3. Histological findings suggest strongly that the pathological changes produced with dextran sulfate are caused primarily by the intravascular precipitates with occlusion of the capillaries.From these facts, it is concluded that the precipitates of fibrinogen with heparinoid may be the cause or at least the major cause of the toxicity of heparinoid.4. The most suitable molecular weight of dextran sulfate for clinical use was found to be 5,300 ~ 6,700, from the maximum value of the product (LD50 · Anticoagulant activity). This product (LD50 · Anticoagulant activity) can be employed generally to assess the comparative merits of various heparinoids.5. Clinical use of the dextran sulfate prepared on this basis gave satisfactory results. No severe reaction was observed. However, two delayed reactions, alopecia and thrombocytopenia, were observed. These two reactions seem to come from the cause other than intravascular precipitation.

Molecular Weights of Factor VIII (AHF) and Factor IX (PTC) by Electron Irradiation

1962 ◽  
Vol 08 (02) ◽  
pp. 270-275 ◽  
Author(s):  
David L Aronson ◽  
John W Preiss ◽  
Michael W Mosesson
Keyword(s):  
Molecular Weight ◽  
Factor Viii ◽  
Electron Irradiation ◽  
Factor Ix ◽  
Molecular Weights

SummaryThe molecular weights of AHF (factor VIII) and of PTC (factor IX) have been estimated by their sensitivity to inactivation by 7 kilovolt electrons. The molecular weight of AHF was found to be 180 000 by this method and that of PTC was found to be 110 000.

scholarly journals Specific Seminal Plasma Fractions Are Responsible for the Modulation of Sperm–PMN Binding in the Donkey

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1388
Author(s):  
Jordi Miró ◽  
Jaime Catalán ◽  
Henar Marín ◽  
Iván Yánez-Ortiz ◽  
Marc Yeste
Keyword(s):  
Molecular Weight ◽  
Sperm Motility ◽  
Seminal Plasma ◽  
Potential Effect ◽  
Polymorphonuclear Neutrophils ◽  
Low Fertility ◽  
Plasma Fractions ◽  
Complex Fluid ◽  
First Time

While artificial insemination (AI) with frozen-thawed sperm results in low fertility rates in donkeys, the addition of seminal plasma, removed during cryopreservation, partially counteracts that reduction. Related to this, an apparent inflammatory reaction in jennies is induced following AI with frozen-thawed sperm, as a high amount of polymorphonuclear neutrophils (PMN) are observed within the donkey uterus six hours after AI. While PMN appear to select the sperm that ultimately reach the oviduct, two mechanisms, phagocytosis and NETosis, have been purported to be involved in that clearance. Remarkably, sperm interacts with PMN, but the presence of seminal plasma reduces that binding. As seminal plasma is a complex fluid made up of different molecules, including proteins, this study aimed to evaluate how different seminal plasma fractions, separated by molecular weight (<3, 3–10, 10–30, 30–50, 50–100, and >100 kDa), affect sperm–PMN binding. Sperm motility, viability, and sperm–PMN binding were evaluated after 0 h, 1 h, 2 h, 3 h, and 4 h of co-incubation at 38 °C. Two seminal plasma fractions, including 30–50 kDa or 50–100 kDa proteins, showed the highest sperm motility and viability. As viability of sperm not bound to PMN after 3 h of incubation was the highest in the presence of 30–50 and 50–100 kDa proteins, we suggest that both fractions are involved in the control of the jenny’s post-breeding inflammatory response. In conclusion, this study has shown for the first time that specific fractions rather than the entire seminal plasma modulate sperm–PMN binding within the donkey uterus. As several proteins suggested to be involved in the control of post-AI endometritis have a molecular weight between 30 and 100 kDa, further studies aimed at determining the identity of these molecules and evaluating their potential effect in vivo are much warranted.

scholarly journals Mesoporous Properties of Bioactive Glass Synthesized by Spray Pyrolysis with Various Polyethylene Glycol and Acid Additions

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 618
Author(s):  
Tzu-Yu Peng ◽  
Pei-Yun Tsai ◽  
May-Show Chen ◽  
Yuichi Mine ◽  
Shan-Hua Wu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Bioactive Glass ◽  
Spray Pyrolysis ◽  
Mesoporous Structure ◽  
High Specific Surface Area ◽  
Process Time ◽  
In Vitro Bioactivity ◽  
One Pot

Mesoporous bioactive glass (MBG) has a high specific surface area, promoting the reaction area, thereby improving the bioactivity; thus, MBG is currently gaining popularity in the biomaterial field. Spray pyrolysis (SP) is a one-pot process that has the advantages of shorter process time and better particle bioactivity, therefore, MBG was prepared by SP process with various polyethylene glycol (PEG, molecular weight ranged from 2000–12,000) and acid (HCl and CH3COOH) additions. In vitro bioactivity and mesoporous properties of the so-obtained MBG were investigated. The experimental results showed that all the MBG exhibited amorphous and mesoporous structure. Increasing the molecular weight of PEG can improve the mesoporous structure and bioactivity of MBG. Whereas optimized MBG was prepared with suitable concentration of PEG and CH3COOH. In the present work, MBG synthesized via spray pyrolysis by adding 5 g of PEG with a molecular weight of 12,000 and 50 mL of CH3COOH exhibited the best in vitro bioactivity and mesoporous structure.

scholarly journals Effects of Molecular Weight of Functionalized Liquid Butadiene Rubber as a Processing Aid on the Properties of SSBR/Silica Compounds

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 850
Author(s):  
Donghyuk Kim ◽  
Byungkyu Ahn ◽  
Kihyun Kim ◽  
JongYeop Lee ◽  
Il Jin Kim ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Anionic Polymerization ◽  
High Performance ◽  
Crosslink Density ◽  
Functional Group ◽  
Vital Role ◽  
Butadiene Rubber ◽  
Molecular Weights ◽  
Mooney Viscosity ◽  
Silica Dispersion

Liquid butadiene rubber (LqBR) which used as a processing aid play a vital role in the manufacturing of high-performance tire tread compounds. However, the studies on the effect of molecular weight, microstructure, and functionalization of LqBR on the properties of compounds are still insufficient. In this study, non-functionalized and center-functionalized liquid butadiene rubbers (N-LqBR and C-LqBR modified with ethoxysilyl group, respectively) were synthesized with low vinyl content and different molecular weights using anionic polymerization. In addition, LqBR was added to the silica-filled SSBR compounds as an alternative to treated distillate aromatic extract (TDAE) oil, and the effect of molecular weight and functionalization on the properties of the silica-filled SSBR compound was examined. C-LqBR showed a low Payne effect and Mooney viscosity because of improved silica dispersion due to the ethoxysilyl functional group. Furthermore, C-LqBR showed an increased crosslink density, improved mechanical properties, and reduced organic matter extraction compared to the N-LqBR compound. LqBR reduced the glass transition temperature (Tg) of the compound significantly, thereby improving snow traction and abrasion resistance compared to TDAE oil. Furthermore, the energy loss characteristics revealed that the hysteresis loss attributable to the free chain ends of LqBR was dominant.

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