scholarly journals Physiological Characteristics of Platelet Activity in Calves of the Dairy and Plant Nutrition of the Holstein Breed

2021 ◽  
Author(s):  
Ilya N. Medvedev ◽  
Nadezhda V. Vorobyev
Keyword(s):  
Biological Significance ◽  
Large Degree ◽  
Early Ontogeny ◽  
Platelet Activity ◽  
Holstein Breed ◽  
Vegetarian Nutrition ◽  
Dairy Plant ◽  
Circulating Platelet Aggregates ◽  
The Stability ◽  
Observation Period

The hemostatic properties of platelets to a large degree determine the activity of metabolic processes that have great biological significance especially in early ontogeny. This study was conducted on 43 calves of the Holstein breed during the phase of milk-vegetable diet. It was found during the observation period that the indicators were stable in the calves between 31 and 60 days of life, and the platelet aggregation weakened. In the blood of the calves of the Holstein breed there was a slight increase in the number of discocytes. The total number of active thrombocytes in calves observed after stability between 31-60 days of life decreased during the follow-up observation. The levels of circulating platelet aggregates of small and large sizes decreased between 60 and 90 days by 66.7% and 2.5 times, respectively. This contributed to a weakening of the calves’ platelet synthesis of thromboxane, a decrease in the content of adenosinfosfatom, and to inhibition of their secretion. During the observation period, the number of actin and myosin in the platelets of the animals also decreased, which reduced the overall platelet activity. In the second part of the phase of lacto-vegetarian nutrition, the synthesis of actin and myosin in the exposed aggregate platelets weakened in the calves. The stability of the hemostatic platelet counts of the Holstein calves at the age of 31-60 days was typical, which changed their physiologically acceptable weakening by the end of observation. Keywords: calves, dairy plant phase, Holstein breed, platelets, aggregation, secretion

scholarly journals The landscape of circulating platelet aggregates in COVID-19

2021 ◽  
Author(s):  
Yuqi Zhou ◽  
Masako Nishikawa ◽  
Hiroshi Kanno ◽  
Tinghui Xiao ◽  
Takuma Suzuki ◽  
...  
Keyword(s):  
Large Scale ◽  
Multiorgan Failure ◽  
Young Patients ◽  
Clinical Feature ◽  
Platelet Activity ◽  
Multiple Organs ◽  
Characteristic Clinical Feature ◽  
Circulating Platelet Aggregates ◽  
Platelet Aggregates ◽  
D Dimer

A characteristic clinical feature of COVID-19 is the frequent occurrence of thrombotic events. Furthermore, many cases of multiorgan failure are thrombotic in nature. Since the outbreak of COVID-19, D-dimer testing has been used extensively to evaluate COVID-19-associated thrombosis, but does not provide a complete view of the disease because it probes blood coagulation, but not platelet activity. Due to this limitation, D-dimer testing fails to account for thrombotic events which occur despite low D-dimer levels, such as sudden stroke in young patients and autopsy-identified widespread microthrombi in multiple organs. Here we report the landscape of circulating platelet aggregates in COVID-19 obtained by large-scale single-cell image-based profiling and temporal monitoring of the blood of COVID-19 patients (n = 110). Surprisingly, our analysis shows the anomalous presence of excessive platelet aggregates in nearly 90% of all COVID-19 patients, including those who were not clinically diagnosed with thrombosis and those with low D-dimer levels (less than 1 ug/mL). Additionally, results indicate a strong link between the concentration of platelet aggregates and the severity and mortality of COVID-19. Finally, high-dimensional analysis and comparison with other diseases reveal that COVID-19 behaves as a product of thrombosis (localized) and infectious diseases (systemic), as a cause of systemic thrombosis.

scholarly journals The effect of hairpin loop on the structure and gene expression activity of the long-loop G-quadruplex

2021 ◽  
Author(s):  
Subramaniyam Ravichandran ◽  
Maria Razzaq ◽  
Nazia Parveen ◽  
Ambarnil Ghosh ◽  
Kyeong Kyu Kim
Keyword(s):  
Gene Expression ◽  
Rna Structure ◽  
Biological Significance ◽  
Cellular Functions ◽  
Hairpin Loops ◽  
G Quadruplex ◽  
Reporter Assays ◽  
Expression Activity ◽  
The Stability ◽  
And Function

Abstract G-quadruplex (G4), a four-stranded DNA or RNA structure containing stacks of guanine tetrads, plays regulatory roles in many cellular functions. So far, conventional G4s containing loops of 1–7 nucleotides have been widely studied. Increasing experimental evidence suggests that unconventional G4s, such as G4s containing long loops (long-loop G4s), play a regulatory role in the genome by forming a stable structure. Other secondary structures such as hairpins in the loop might thus contribute to the stability of long-loop G4s. Therefore, investigation of the effect of the hairpin-loops on the structure and function of G4s is required. In this study, we performed a systematic biochemical investigation of model G4s containing long loops with various sizes and structures. We found that the long-loop G4s are less stable than conventional G4s, but their stability increased when the loop forms a hairpin (hairpin-G4). We also verified the biological significance of hairpin-G4s by showing that hairpin-G4s present in the genome also form stable G4s and regulate gene expression as confirmed by in cellulo reporter assays. This study contributes to expanding the scope and diversity of G4s, thus facilitating future studies on the role of G4s in the human genome.

Biological Role of Magnesium

1958 ◽  
Vol 4 (6) ◽  
pp. 429-451 ◽  
Author(s):  
A La Pleshchitser
Keyword(s):  
Atmospheric Oxygen ◽  
Biological Significance ◽  
Biological Role ◽  
Living Matter ◽  
Antagonistic Action ◽  
Biochemical Processes ◽  
The Central Nervous System ◽  
The Stability ◽  
Labile Equilibrium

Abstract Fersman (1934) commented on the relatively unimportant role of magnesium in biochemical processes. The comparatively limited radius of its ions, the stability and relative insolubility of its compounds prevent its taking an active part in the reactions of living matter. On the other hand, we have the statement of Vernadskii that in the plankton film of the ocean, in the ordinary accumulations and more massive growths, the amount of magnesium-containing chlorophyll must reach the order of 10-4 per cent by weight, if not higher, so that a small quantity of magnesium, entering into the composition of the chlorophyll-complex of the plankton, ultimately regulates the main part of the oxygenating function of living matter, the creation of free atmospheric oxygen. The material summarized by us likewise affords evidence of the importance of the role of magnesium in biological processes. All this, however, does not justify sharp differentiation between the biological role of magnesium and its role in biochemical processes. In all probability these processes are conditional to each other, although they are not identical processes. It is important to note the established and incontestable role of magnesium in many enzymatic processes in both the plant and animal kingdoms. The antagonistic action between magnesium and calcium, resulting from artificial changes in the ratios of these elements in soil, plants, and animals, can hardly occur under natural conditions, and, conversely, it must be assumed that a labile equilibrium between these elements is always maintained. The depressing action of magnesium ions on the central nervous system acquires considerable biological significance, since this permits the assumption that these ions in the animal organism may facilitate inhibitory processes in the nerve cell and insure the normal course of catabolic and anabolic processes. The narcotic and cholinolytic effects of magnesium constitute the basis for the wide therapeutic use of magnesium salts in medical practice.

Studies on the stability of creatine kinase isozymes

2003 ◽  
Vol 81 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Zhi Guo ◽  
Zheng Wang ◽  
Xicheng Wang
Keyword(s):  
Differential Scanning Calorimetry ◽  
Creatine Kinase ◽  
Freeze Drying ◽  
Biological Significance ◽  
Subunit Interactions ◽  
Scanning Calorimetry ◽  
Gradient Gel Electrophoresis ◽  
The Stability ◽  
Creatine Kinase Isozymes ◽  
Monomer Form

Research on the stabilizing properties of creatine kinase isozymes CK-BB, CK-MB, and CK-MM showed that minor alteration of their sequence and structure influenced their stability significantly. An analysis of the stability of the isozymes in storage after freeze drying indicates that creatine kinase isozymes are all in monomer form because of the loss of subunit interactions. Freeze-drying leads to the oxidization of CK-BB and rearrangement of CK-MB. There are also differences in the unfolding of the isozymes in urea. CK-BB and CK-MB are unfolded in lower urea concentrations than CK-MM. Differences in the thermal unfolding were also examined by differential scanning calorimetry. This paper discusses the potential biological significance of these results.Key words: creatine kinase isozymes, fluorescence, circular dichroism, differential scanning calorimetry, urea gradient gel electrophoresis.

scholarly journals A Spiral of Distrust: A Panel Study on the Relation between Political Distrust and Protest Voting in Belgium

2016 ◽  
Vol 53 (1) ◽  
pp. 104-130 ◽  
Author(s):  
Marc Hooghe ◽  
Ruth Dassonneville
Keyword(s):  
Safety Valve ◽  
Panel Study ◽  
Political Trust ◽  
Panel Analysis ◽  
Political Distrust ◽  
Dynamic Perspective ◽  
Low Levels ◽  
The Stability ◽  
The Relationship ◽  
Observation Period

Low levels of political trust are associated with a preference for protest parties. Some authors have argued that in this manner protest parties indirectly contribute to the stability of electoral democracy, functioning as a ‘safety valve’ for political discontent. In this article, we investigate the relationship between protest voting and political trust in a dynamic perspective, relying on a five-year Belgian panel study. We confirm that citizens with low levels of political trust are more likely to vote for protest parties. Additionally, we point out that decreasing levels of trust significantly increase the probability of voting for a protest party, even controlling for absolute levels of trust. Most importantly, having voted for a protest party in 2009 is linked to a subsequent further drop in political trust during the 2009–14 observation period. The panel analysis suggests that distrust and protest voting reinforce one another, leading to a potential spiral of distrust.

scholarly journals Ecological-phytocenotic analysis of the field layer of urban recreational forests (on the example of Kaluga and Obninsk)

2020 ◽  
pp. 68-75
Author(s):  
A. A. Evseeva
Keyword(s):  
Forest Ecosystems ◽  
Urban Forests ◽  
Practical Significance ◽  
Anthropogenic Pressure ◽  
Forest Communities ◽  
Field Layer ◽  
The Stability ◽  
The City ◽  
Forest Habitats ◽  
Observation Period

The aim of this study is to study the diversity of the ecological-coenotic structure of the field layer of the residual urban forests, using as an example the cities Kaluga and Obninsk, which have different approaches to the conservation of residual forest communities in the city. Obninsk practices the conservation of forest zones that have entered the urban environment as recreational objects, while in Kaluga, such forest communities are in a state of interrupted succession and have experienced forestry activities. The objectives of the study are to study the ecological-coenotic and ecological-biological spectra of the field layer of forest ecosystems, and to identify adventive and protected plant species. The study took place in 2014–2015. In the forest communities under study, 30 sites were selected for geobotanical descriptions by the Braun-Blanquet method at different periods of the growing season (in June and August) to fully cover floristic diversity. A total during the observation period were made 240 floristic descriptions. Kaluga city forests turned out to be more susceptible to negative changes occurring in conditions of recreational for-est management. The field layer of the Kaluga forest recreational zones turned out to be more susceptible to negative changes occurring under the influence of anthropogenic pressure, in comparing with the Obninsk forest recreational zones. This is ex-pressed in the proportion of ecological-coenotic and ecological-biological groups, the presence of a greater number of alien species in the studied communities of Kaluga, which indicates greater resistance to the recreational load of the city forests of Obninsk. For example, the share of the group of forest habitats is much higher in Obninsk, where forest species make up more than half of all types of grass layer (54,2%). In the Kaluga forests, the share of forest habitats is lower and amounted to 47,5%. The discovered difference in the stability of the field layer of the Obninsk forests is presumably due to the strategy of their conservation in the urban area in a state of natural succession. The practical significance of the results obtained can be the possibility of using them to determine the degree of negative changes in recreational forests. The direction of further research can be directed at organizing monitoring of the urban forests of Kaluga and Obninsk according to the state of the field layer

scholarly journals A preliminary investigation of in vitro anti-thrombotic and anti-platelet activity of Pinus Gerardiana

2017 ◽  
Vol 4 (1) ◽  
pp. 1098 ◽  
Author(s):  
Atta-ur Rehman ◽  
Sara Naz ◽  
Muhammad Zaman ◽  
Syed Saeed-ul-Hassan ◽  
Javed Iqbal ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Blood Clot ◽  
Preliminary Investigation ◽  
Circulatory System ◽  
Clot Lysis ◽  
Platelet Activity ◽  
In Vivo Models ◽  
The Stability

Introduction: Hemostasis is a process which preserves the stability of a closed and high-pressure circulatory system after any vascular injury. Circulating platelets are recruited to the site of injury, where they develop a major component of the developing thrombus, blood clotting, started by tissue factor, concludes in the generation of thrombin and fibrin. Thrombosis is a serious event in the arterial diseases and a major cause in the development of myocardial infarction, stroke and venous thrombo-embolism which justify prominent morbidity and mortality rate. The knowledge of molecular and cellular mechanism of the formation of thrombus has developed considerably in the recent studies by using different in-vitro and in-vivo models of diseases. P. gerardiana nut oil has been reported to possess anti-bacterial, anti-fungal, anti-viral, anti-septic, anti-neuralgic, diuretic, expectorant, hypertensive properties. However, hardly, any data is available regarding effects of nut oil on platelet function. In this study, fibrinolytic activity and effect on platelet aggregation were investigated. Method: P. gerardiana nut oil was extracted by using n-Hexane and then concentrated by rotary evaporator. Anti-thrombotic and fibrinolytic activities were evaluated on blood clot formation. Effects on platelet aggregation of the oil were determined based on collagen or epinephrine induced platelet aggregation. Results: P. gerardiana caused blood clot lysis in-vitro. P. gerardiana nut oil inhibited collagen dependent platelet aggregation while accelerated the epinephrine dependent platelet aggregation. In vitro whole blood coagulation was also reduced. In vivo P. gerardiana nut oil has no significant effect on blood cell indices. Conclusion: P. gerardiana nuts oil can be an effective therapy for the treatment of cardiovascular disorders and thromboembolism.

scholarly journals Role of Heat Shock Proteins (HSP70 and HSP90) in Viral Infection

2021 ◽  
Vol 22 (17) ◽  
pp. 9366
Author(s):  
Anna Lubkowska ◽  
Waldemar Pluta ◽  
Aleksandra Strońska ◽  
Alicja Lalko
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Viral Replication ◽  
Viral Infection ◽  
Viral Infections ◽  
Therapeutic Potential ◽  
Biological Significance ◽  
Hsp70 Family ◽  
The Stability ◽  
Shock Proteins

Heat shock proteins (HSPs) are a large group of chaperones found in most eukaryotes and bacteria. They are responsible for the correct protein folding, protection of the cell against stressors, presenting immune and inflammatory cytokines; furthermore, they are important factors in regulating cell differentiation, survival and death. Although the biological function of HSPs is to maintain cell homeostasis, some of them can be used by viruses both to fold their proteins and increase the chances of survival in unfavorable host conditions. Folding viral proteins as well as replicating many different viruses are carried out by, among others, proteins from the HSP70 and HSP90 families. In some cases, the HSP70 family proteins directly interact with viral polymerase to enhance viral replication or they can facilitate the formation of a viral replication complex and/or maintain the stability of complex proteins. It is known that HSP90 is important for the expression of viral genes at both the transcriptional and the translational levels. Both of these HSPs can form a complex with HSP90 and, consequently, facilitate the entry of the virus into the cell. Current studies have shown the biological significance of HSPs in the course of infection SARS-CoV-2. A comprehensive understanding of chaperone use during viral infection will provide new insight into viral replication mechanisms and therapeutic potential. The aim of this study is to describe the molecular basis of HSP70 and HSP90 participation in some viral infections and the potential use of these proteins in antiviral therapy.

scholarly journals A stochastic mathematical model of two different infectious epidemic under vertical transmission

2021 ◽  
Vol 19 (3) ◽  
pp. 2179-2192
Author(s):  
Xunyang Wang ◽  
◽  
Canyun Huang ◽  
Yixin Hao ◽  
Qihong Shi ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Vertical Transmission ◽  
Biological Significance ◽  
Sufficient Conditions ◽  
Discussion Section ◽  
Stochastic Permanence ◽  
Stochastic Epidemic ◽  
The Stability ◽  
Well Posed ◽  
Theoretical Results

<abstract><p>In this study, considering the effect of environment perturbation which is usually embodied by the alteration of contact infection rate, we formulate a stochastic epidemic mathematical model in which two different kinds of infectious diseases that spread simultaneously through both horizontal and vertical transmission are described. To indicate our model is well-posed and of biological significance, we prove the existence and uniqueness of positive solution at the beginning. By constructing suitable $ Lyapunov $ functions (which can be used to prove the stability of a certain fixed point in a dynamical system or autonomous differential equation) and applying $ It\hat{o} $'s formula as well as $ Chebyshev $'s inequality, we also establish the sufficient conditions for stochastic ultimate boundedness. Furthermore, when some main parameters and all the stochastically perturbed intensities satisfy a certain relationship, we finally prove the stochastic permanence. Our results show that the perturbed intensities should be no greater than a certain positive number which is up-bounded by some parameters in the system, otherwise, the system will be surely extinct. The reliability of theoretical results are further illustrated by numerical simulations. Finally, in the discussion section, we put forward two important and interesting questions left for further investigation.</p></abstract>

scholarly journals Duplex formation in a G-quadruplex bulge

2020 ◽  
Vol 48 (18) ◽  
pp. 10567-10575 ◽  
Author(s):  
Thi Quynh Ngoc Nguyen ◽  
Kah Wai Lim ◽  
Anh Tuân Phan
Keyword(s):  
Base Pair ◽  
Solution Structure ◽  
Biological Significance ◽  
Consensus Definition ◽  
Quadruplex Structure ◽  
G Quadruplex ◽  
Structural Details ◽  
The Stability ◽  
Definition Of ◽  
Duplex Formation

Abstract Beyond the consensus definition of G-quadruplex-forming motifs with tracts of continuous guanines, G-quadruplexes harboring bulges in the G-tetrad core are prevalent in the human genome. Here, we study the incorporation of a duplex hairpin within a bulge of a G-quadruplex. The NMR solution structure of a G-quadruplex containing a duplex bulge was resolved, revealing the structural details of the junction between the duplex bulge and the G-quadruplex. Unexpectedly, instead of an orthogonal connection the duplex stem was observed to stack below the G-quadruplex forming a unique quadruplex–duplex junction. Breaking up of the immediate base pair step at the junction, coupled with a narrowing of the duplex groove within the context of the bulge, led to a progressive transition between the quadruplex and duplex segments. This study revealed that a duplex bulge can be formed at various positions of a G-quadruplex scaffold. In contrast to a non-structured bulge, the stability of a G-quadruplex slightly increases with an increase in the duplex bulge size. A G-quadruplex structure containing a duplex bulge of up to 33 nt in size was shown to form, which was much larger than the previously reported 7-nt bulge. With G-quadruplexes containing duplex bulges representing new structural motifs with potential biological significance, our findings would broaden the definition of potential G-quadruplex-forming sequences.

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