scholarly journals STUDY OF THE EFFECT OF THE PHYSICOCHEMICAL PROPERTIES OF CHITOSAN ON ITS HAEMOSTATIC ACTIVITY

2021 ◽  
Vol 26 ◽  
pp. 112-120
Author(s):  
Oksana V. Kadyseva ◽  
◽  
Vladimir N. Bykov ◽  
Olga Y. Strelova ◽  
Alexander N. Grebenyuk ◽  
...  
Keyword(s):  
Conformational Transition ◽  
Raw Materials ◽  
Physicochemical Characteristics ◽  
Biological Properties ◽  
In Vivo Experiments ◽  
Haemostatic Agents ◽  
Rigid Rod ◽  
Definition Of

Chitosan are biopolymers that are actively used for the production of local haemostatic agents. The physicochemical characteristics that determine its biological properties include the molecular weight and the deacetylation degree. However, there is no linear relationship between these parameters and haemostatic activity. The most reliable method of confirming the effectiveness is still in vivo experiments. The ability to initiate haemostasis depends on the conformational transition of chitosan macromolecules. The highest efficiency in vitro was for samples in which the transition of a significant part of the molecules from the ‘rigid rod’ state to the ‘globule’ occurred at physiological pH. It is proposed to expand the list of indicators of chitosan that can be controlled to evaluate the quality of raw materials, related to haemostatic activity, to include the definition of the conformational transition at physiological pH.

scholarly journals Combination of in vivo phage therapy data with in silico model highlights key parameters for treatment efficacy

2021 ◽  
Author(s):  
Raphaelle Delattre ◽  
Jeremy Seurat ◽  
Feyrouz Haddad ◽  
Thu-Thuy Nguyen ◽  
Baptiste Gaborieau ◽  
...  
Keyword(s):  
Phage Therapy ◽  
Biological Properties ◽  
General Strategy ◽  
In Vivo Experiments ◽  
Bacterial Dynamics ◽  
Optimal Dosing ◽  
Dosing Regimens ◽  
The Impact

The clinical (re)development of phage therapy to treat antibiotic resistant infections requires grasping specific biological properties of bacteriophages (phages) as antibacterial. However, identification of optimal dosing regimens is hampered by the poor understanding of phage-bacteria interactions in vivo. Here we developed a general strategy coupling in vitro and in vivo experiments with a mathematical model to characterize the interplay between phage and bacterial dynamics during pneumonia induced by a pathogenic strain of Escherichia coli. The model estimates some key parameters for phage therapeutic efficacy, in particular the impact of dose and route of administration on phage dynamics and the synergism of phage and the innate immune response on the bacterial clearance rate. Simulations predict a low impact of the intrinsic phage characteristics in agreement with the current semi-empirical choices of phages for compassionate treatments. Model-based approaches will foster the deployment of future phage therapy clinical trials.

scholarly journals Clitoria ternatea - Shifting Paradigms: From Laboratory to Industry

2021 ◽  
pp. 18-26
Author(s):  
C. B. Ranaweera ◽  
A. K. Chandana
Keyword(s):  
Folk Medicine ◽  
Biological Properties ◽  
Biologically Active ◽  
Potential Health ◽  
Clitoria Ternatea ◽  
In Vivo Experiments ◽  
Industrial Level ◽  
New Treatments

Clitoria ternatea commonly known as Butterfly pea is a standard Ayurvedic medicinal plant used in many parts of south Asian countries. Traditional medicinal plants are a great alternative to find new treatments and for the development of novel antimicrobials to combat many diseases. In Ayurveda and traditional and folk medicine in several countries, decoction and extracts made from C. ternatea are recommended to be used for various medical treatments. C. ternatea extracts claimed to possess antibacterial, antiviral, and antifungal properties, which had been supported and validated by many in vitro and in vivo experiments. However, biologically active compound/s isolation and development novel compounds still remain in its infancy. Despite its enormous potential health benefits, only a single commercial product managed to reach industrial level production. C. ternatea cyclotide studies are also limited despite the fact that it the fastest known natural ligase discovered to date. These cyclotides are rapid peptide ligators and has been the focus of many recent studies on peptide ligation and cyclization for biotechnological applications. In this mini summary we have tried to point out innate unique biological properties of C. ternatea and suggested few future studies, more specifically on C. ternatea cyclotides development against bacterial heat shock proteins (Hsp 100) for novel antimicrobial discovery and development.

scholarly journals THE SAFETY OF PHOTOSENSITIZERS AS A PREVENTIVE DRUG FOR INDUSTRIAL POULTRY FARMING

2021 ◽  
Vol 1 (7(71)) ◽  
pp. 8-14
Author(s):  
T. Gryazneva ◽  
V. Shlionskiy ◽  
A. Shlionskaya
Keyword(s):  
Raw Materials ◽  
Well Being ◽  
Female Rats ◽  
White Female ◽  
Poultry Products ◽  
In Vivo Experiments ◽  
Preventive Drug ◽  
Production Animals ◽  
Definition Of

The aim of the work was to determine the safety of the use of photosensitizers as a preventive drug for industrial animals. In the theoretical part, the definition of photosensitizers was given with a description of the reactions in which they enter into biological systems, the purpose of the work and the tasks were formulated. In the practical part, the effectiveness of the Photoditazine photosensitizer was determined in order to maintain the well-being of the livestock of industrial birds and to obtain high-quality and safe poultry products. In vivo experiments were conducted to determine the effectiveness of photosensitizers as a preventive drug for production animals. Studies were also conducted to determine the safety of products obtained from experimental animals by feeding their meat to laboratory rats with further determination of their pancreatic elastase concentration by ELISA. For the experiments, non-linear white female rats were selected as the most adequate test object for rapid analysis of the safety of raw materials obtained after the use of photosensitizers.

Resazurin Method for Evaluation of Bioactive Compounds from Cranberry Extracts Using the Metabolic Activity of a ΔSOD1 Mutant of Saccharomyces cerevisiae Yeast Under Severe Osmotic Stress

2020 ◽  
Vol 103 (2) ◽  
pp. 422-427
Author(s):  
Agata Święciło ◽  
Kamila Rybczyńska-Tkaczyk
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Parameters ◽  
Raw Materials ◽  
Antioxidant Properties ◽  
Biological Properties ◽  
Biologically Active ◽  
Antioxidant Compounds ◽  
Alcohol Water

Abstract Background: In addition to nutrients, plant raw materials for food production should also contain substances with beneficial biological properties, which unquestionably include antioxidant compounds. Among the numerous methods of determining the antioxidant properties of samples of plant material, biological methods that provide information about not only the in vivo antioxidant potential of samples but also their metabolism and bioavailability are increasingly valued. Objective: The aim of the study was to assess the antioxidant properties of extracts from large cranberry (Vaccinium macrocarpon) obtained from different producers. Methods: Biologically active compounds were extracted from cranberry fruits using water alone and ethyl alcohol–water in proportions of 1+1 and 4+1 (v/v) as solvents. The following were determined in the extracts: content of phenolic compounds and anthocyanins, total antioxidant capacity based on reduction of the ABTS+• [2,20-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)] radical cation, and antioxidant properties as reflected by the growth of a Saccharomyces cerevisiae Δsod1 mutant in a liquid hypertonic environment. The growth parameters of this Δsod1 mutant, monitored by a method exploiting a color reaction with resazurin, reflected the antioxidant properties of the extracts. Results: The ethanol–water cranberry extracts showed higher content of polyphenols, anthocyanins, and total antioxidants expressed as Trolox equivalent, determined on the basis of ABTS+• reduction. Conclusions: The antioxidant properties determined by the bioassay did not respond strongly to the data obtained in the in vitro chemical and biochemical assays, because they were more closely associated with the batch of fruit than with the type of solvent used to extract phytochemicals.

Extracts and Flavonoids of Passiflora Species as Promising Anti-inflammatory and Antioxidant Substances

2020 ◽  
Vol 26 ◽  
Author(s):  
Marcin Ożarowski ◽  
Tomasz M. Karpiński
Keyword(s):  
Raw Materials ◽  
New Drugs ◽  
Current Standard ◽  
Inflammatory Processes ◽  
Anti Inflammatory ◽  
Definition Of ◽  
Promising Source ◽  
Plant Substances

: There is increasing interest in evaluating anti-inflammatory activities of plant substances such as extracts and flavonoid rich fractions. A promising source of new medicinal drugs may be species from the Passifloraceae family. The most interesting group of principal chemical compounds in Passiflora species are polyphenolic compounds, including flavonoids due to their antioxidant activity demonstrated in various studies (quercetin, rutin, apigenin, luteolin, chrysin, and Cglycosylflavones i.e., vitexin, isovitexin, orientin, isoorientin). However, each extracts from Passiflora spp. as multi-component mixtures should be estimated for chemical composition (in the standardization process) and their activity using in vitro and in vivo tests. The current standard for drug discovery and development from plants indicates that only collective assessment allows estimating plant substances by definition of the origin of raw materials and their quality, methods of extractions, and metabolite profiles. Increasingly, due to complex phytochemical procedures to obtain extracts, individual flavonoid compounds are also tested for anti-inflammatory action. However, it should be emphasized that various sources of potential new drugs from plant origin are not mutually exclusive, but are complementary. A review of bibliographic data includes the following information about Passiflora species, such as distribution, classification, phytochemical compounds, antiinflammatory activity of extracts, anti-inflammatory activity of flavonoids, and antioxidant potential. The review allows concluded that extracts and flavonoids (mainly quercetin, apigenin, and vitexin) from Passiflora spp. can be a valuable source of anti-inflammatory and anti-oxidative medications for the prevention and treatment of many diseases, which occur with complex inflammatory processes.

scholarly journals Convergent synthesis of diversified reversible network leads to liquid metal-containing conductive hydrogel adhesives

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yong Xu ◽  
Rebecca Rothe ◽  
Dagmar Voigt ◽  
Sandra Hauser ◽  
Meiying Cui ◽  
...  
Keyword(s):  
Liquid Metal ◽  
Polymer Networks ◽  
Biological Properties ◽  
Self Healing ◽  
Convergent Synthesis ◽  
Chemical Structures ◽  
In Vivo Experiments ◽  
Macromolecular System

AbstractMany features of extracellular matrices, e.g., self-healing, adhesiveness, viscoelasticity, and conductivity, are associated with the intricate networks composed of many different covalent and non-covalent chemical bonds. Whereas a reductionism approach would have the limitation to fully recapitulate various biological properties with simple chemical structures, mimicking such sophisticated networks by incorporating many different functional groups in a macromolecular system is synthetically challenging. Herein, we propose a strategy of convergent synthesis of complex polymer networks to produce biomimetic electroconductive liquid metal hydrogels. Four precursors could be individually synthesized in one to two reaction steps and characterized, then assembled to form hydrogel adhesives. The convergent synthesis allows us to combine materials of different natures to generate matrices with high adhesive strength, enhanced electroconductivity, good cytocompatibility in vitro and high biocompatibility in vivo. The reversible networks exhibit self-healing and shear-thinning properties, thus allowing for 3D printing and minimally invasive injection for in vivo experiments.

scholarly journals Sulfated Polysaccharides From Sea Algae as the Basis of Modern Biotechnologies for Creating Wound Coverings: Current Achievements and Coming Prospects

2020 ◽  
Author(s):  
Boris Andryukov ◽  
Natalya Besednova ◽  
Tatyana Kuznetsova ◽  
Tatyana Zaporozhets ◽  
Svetlana Ermakova ◽  
...  
Keyword(s):  
Wound Healing ◽  
Clinical Trial Data ◽  
Biological Properties ◽  
Biologically Active ◽  
Wound Dressings ◽  
Sulfated Polysaccharides ◽  
Accelerate Wound Healing ◽  
In Vivo Experiments

Wound healing involves a complex cascade of cellular, molecular, and biochemical responses and signaling processes. It consists of successive interrelated phases, the duration of which depends on multifactorial processes. Wound treatment is a major healthcare issue that can be resolved by development of effective and affordable wound dressings based on natural materials and biologically active substances. Proper use of modern wound dressings can significantly accelerate wound healing with minimal cosmetic defects. The innovative biotechnologies for creating modern natural interactive dressings are based on sulfated polysaccharides from seaweeds with their unique structures and biological properties, the availability of their sources in the form of wild bushes, and in the form of aquaculture, as well as with a high potential for participation in process control wound healing. These natural biopolymers are a novel and promising biologically active source for designing wound dressings based on alginates, fucoidans, carrageenans, and ulvans, which serve as active and effective therapeutic tools. The aim of this review is to summarize available information about the modern wound dressing’s technologies based on seaweed-derived polysaccharides, including those successfully implemented in commercial products, with the emphasis on promising and innovative designs. The further prospect of using marine biopolymers is related to the need to analyze the results of numerous in vitro and in vivo experiments, summarize clinical trial data, develop a scientifically based approach and relevant practical recommendations for the treatment of wounds.

The Geometrical Arrangement of Knee Constraints That Makes Natural Motion Possible: Theoretical and Experimental Analysis

2019 ◽  
Vol 141 (5) ◽  
Author(s):  
Michele Conconi ◽  
Nicola Sancisi ◽  
Vincenzo Parenti-Castelli
Keyword(s):  
Fundamental Property ◽  
Metabolic Cost ◽  
Helical Axis ◽  
Natural Motion ◽  
In Vivo Experiments ◽  
Definition Of ◽  
Resultant Forces ◽  
And Cartilage

The study of the knee natural motion, namely the unresisted motion that the knee exhibits in the absence of external loads, provides insights into the physiology of this articulation. The natural motion represents the baseline condition upon which deformations of its passive structures (i.e., ligaments and cartilage) take place when loads are applied. Moreover, during natural motion, the strain energy density stored within ligaments and cartilage is minimized. This reduces the chance of microdamage occurrences and the corresponding metabolic cost for tissue repairing. The study of the knee natural motion is thus fundamental in understanding the joint physiology. This paper shows that the line of action of resultant forces of all the knee constraints provided by the passive structures must intersect the instantaneous helical axis (IHA) to make the knee natural motion possible. In other words, the lines of action of all these constraints must cross the same line at each flexion angle to guarantee the natural motion of the joint. This geometrical property is first proven theoretically and then verified in four in vitro and one in vivo experiments. The geometrical characterization of the knee natural motion presented in this study provides a fundamental property that must be satisfied to allow the correct joint mobility. The knowledge of this property may thus allow the definition of better models, treatments, and devices.

scholarly journals Lady's mantle (Alchemilla vulgaris L., Rosaceae): A review of traditional uses, phytochemical profile, and biological properties

2020 ◽  
pp. 66-74
Author(s):  
Vanja Tadić ◽  
Nemanja Krgović ◽  
Ana Žugić
Keyword(s):  
Biological Activities ◽  
Folk Medicine ◽  
Biological Properties ◽  
Chemical Profile ◽  
In Vivo Experiments ◽  
Gastrointestinal Complaints ◽  
Phytochemical Profile ◽  
Phenolcarboxylic Acids

Lady's mantle (Alchemilla vulgaris L. syn. Alchemilla xanthochlora Rothm., Rosaceae) has been commonly used in folk medicine to heal inflammations in the mouth, bleeding of the nose, furuncules, gynaecological (menorrhagia and dysmenorrhoea), and gastrointestinal disorders. Although therapeutic indications for lady's mantle are non-specific diarrhoea and gastrointestinal complaints, it has been reported to exert, as well, a variety of biological activities, including wound healing, antimicrobial, neuroprotective, gastroprotective, cytotoxic, and antioxidant. Lady's mantle presents a valuable source of natural bioactive compounds, mostly phenolic compounds - a large amount of tannins, phenolcarboxylic acids, and flavonoids, being responsible for the abovementioned effects. In this work, a literature review of biological properties, investigated in in vitro and in vivo experiments in regard to the determined chemical profile is presented. In addition, the data reported are discussed, and the directions for further investigations are proposed.

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