scholarly journals Experimental Modeling of Osteoporosis in Animals

2021 ◽  
Vol 11 (3) ◽  
pp. 97-109
Author(s):  
N.V. Dedukh ◽  
N.N. Yakovenchuk ◽  
O.A. Nikolchenko
Keyword(s):  
Experimental Studies ◽  
Clinical Manifestations ◽  
Experimental Models ◽  
Specific Aspect ◽  
Factors Affecting ◽  
Surgical Methods ◽  
Radiation Induced ◽  
Severe Pathology ◽  
Similarity And Difference ◽  
Rats And Mice

Experimental studies on animals under conditions of osteopenia and osteoporosis modeling significantly expand the view of the mechanisms of primary and secondary osteoporosis development, help determining the effect of various factors affecting the bone tissue, evaluate the effect of medications, new biomaterials, etc. Osteoporosis is a multifactorial disease; its clinical manifestations depend on a complex interplay of environmental, lifestyle and genetic factors. The review of the literature analyzes the data on the use of animals to assess the features of osteoporosis course when modeling this pathology by surgical and non-surgical methods. The article features the models of osteoporosis which are reproduced on rats and mice being the most accessible objects and the most frequently used by experimenters. The details of modeling the course of such types of osteoporosis as postmenopausal, senile, glucocorticoid-induced, testosterone deficiency (orchiectomy)-induced, immobilization, hypothermia, radiation-induced, etc. are explored. A specific aspect of recent advances in modeling osteoporosis is the creation of transgenic and knockout mice, whose models may be used to detect components of genetic lesions and will certainly contribute to the development of new methods of prevention and therapy of this severe pathology. The similarity and difference of experimental models of osteoporosis describing the pathophysiological changes in humans due to osteoporosis are noted. Emphasis is placed on bioethical norms of working with experimental animals.

scholarly journals Autoimmune Uveitis. Review

2019 ◽  
Vol 16 (1) ◽  
pp. 5-11
Author(s):  
A. N. Plekhanov ◽  
A. S. Fomina ◽  
O. P. Sverkunova ◽  
J. V. Ivanova
Keyword(s):  
Rapid Development ◽  
Clinical Manifestations ◽  
Sharp Decrease ◽  
Experimental Models ◽  
Review Of The Literature ◽  
Autoimmune Uveitis ◽  
Factors Affecting ◽  
Number Of Patients ◽  
Intractable Problem ◽  
Short Time

For many years in ophthalmology there is a complex intractable problem associated with inflammation of the vascular membrane of the eye, the so-called uveitis. Experts around the world are trying to understand this heterogeneous pathology of the visual organ, in a short time, which can lead to a sharp decrease in visual acuity, the development of severe complications and further disability. The number of patients with inflammation of the vascular tract is growing rapidly every year, the age is younger. The clinical picture of this pathology has changed slightly. Often began to manifest itself in two radically different directions. It proceeds as a sluggish form or vice versa manifests itself more aggressively with the rapid development of clinical manifestations in a short time. Currently, there is evidence of endogenous causes of uveitis.The article provides a review of the literature summarizing modern views on the problem of autoimmune uveitis. New factors affecting the etiology, pathogenesis of the disease, some aspects of therapy are considered. In addition, the main experimental models of autoimmune diseases of the vascular tract of the eye are analyzed.

scholarly journals Particularities of Experimental Models Used to Induce Gastric Ulcer

2019 ◽  
Vol 25 (4) ◽  
pp. 179-184
Author(s):  
Simona Fulga ◽  
Ana-Maria Pelin ◽  
Cristina Mihaela Ghiciuc ◽  
Elena Cătălina Lupușoru
Keyword(s):  
Gastric Ulcer ◽  
Hydrochloric Acid ◽  
Experimental Studies ◽  
Experimental Models ◽  
New Drugs ◽  
Laboratory Animals ◽  
Gastric Ulcers ◽  
Current Therapy ◽  
Surgical Methods

Abstract Introduction: Gastric ulcer is one of the most common gastrointestinal diseases, therefore the constant interest for new treatments is due to adverse effects induced by current therapy. The restricted number of in vivo experimental models is a challenge for researchers. Objectives: Identifying the particularities of different types of experimentally induced gastric ulcer in laboratory animals to facilitate their choise for the study of new antiulcer drugs. Material and method: A search in PubMed and Scopus using keywords ( “experimentally” AND “gastric ulcer” AND “rats/mice”) to include experimental studies with the description of local-induced changes. Review articles and in vitro studies were excluded. Results and discussions: Experimental researches on new drugs for gastric ulcer use chemical or surgical methods to induce gastric lesions in rats. Non-steroidal anti-inflammatory drugs (NSAIDs) and acetic acid models to investigate antisecretory and cytoprotective effects; ethanol models evaluate cytoprotective and/or antioxidant effects; pylorus ligature models to evaluate the effects on the secretion of aggressive gastric factors (hydrochloric acid or pepsin). NSAIDs (indomethacin, acetylsalicylic acid or ibuprofen) inhibit cyclooxygenase activity, resulting from reduced mucus and bicarbonate secretion, decreased mucosal blood flow, alteration of microvascular structures, causing epithelial damage Ethanol enhances the proteolytic and hydrolytic action of hydrochloric acid and pepsin; in addition, stimulates the acid secretion and disruptes vascular endothelium. Pylorus ligature determines the accumulation of gastric acid resulting in gastric ulcers due to the autodigestion of the mucosa. Conclusion: The knowledge of the mechanisms to induce experimental gastric ulcers is essential for choosing the model to evaluate new antiulcer agents.

DIESEL ENGINE OPERATION IN USE OF FUEL WITH ADDITIVES

2018 ◽  
pp. 18-24
Author(s):  
Petar Kazakov ◽  
Atanas Iliev ◽  
Emil Marinov
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Diesel Fuel ◽  
Internal Combustion Engines ◽  
Experimental Studies ◽  
Combustion Engines ◽  
Engine Operation ◽  
Factors Affecting ◽  
Operating Modes ◽  
Positive Effects

Over the decades, more attention has been paid to emissions from the means of transport and the use of different fuels and combustion fuels for the operation of internal combustion engines than on fuel consumption. This, in turn, enables research into products that are said to reduce fuel consumption. The report summarizes four studies of fuel-related innovation products. The studies covered by this report are conducted with diesel fuel and usually contain diesel fuel and three additives for it. Manufacturers of additives are based on already existing studies showing a 10-30% reduction in fuel consumption. Comparative experimental studies related to the use of commercially available diesel fuel with and without the use of additives have been performed in laboratory conditions. The studies were carried out on a stationary diesel engine СМД-17КН equipped with brake КИ1368В. Repeated results were recorded, but they did not confirm the significant positive effect of additives on specific fuel consumption. In some cases, the factors affecting errors in this type of research on the effectiveness of fuel additives for commercial purposes are considered. The reasons for the positive effects of such use of additives in certain engine operating modes are also clarified.

METHODS FOR SIMULATION OF ACUTE BRAIN ISCHEMIA: PATHOPHYSIOLOGICAL SUBSTANTIATION OF SELECTION AND IMPORTANCE FOR CLINICAL PRACTICE

2019 ◽  
pp. 142-152
Author(s):  
Б.И. Гельцер ◽  
Э.В. Слабенко ◽  
Ю.В. Заяц ◽  
В.Н. Котельников
Keyword(s):  
Clinical Practice ◽  
Experimental Studies ◽  
Cerebrovascular Diseases ◽  
Experimental Models ◽  
Pathological Process ◽  
Ischemic Brain ◽  
Actual Clinical Practice ◽  
Acute Cerebral Ischemia ◽  
Different Types ◽  
Acute Brain Ischemia

Одним из основных требований к разработке экспериментальных моделей цереброваскулярных заболеваний является их максимальная приближенность к реальной клинической практике. В работе систематизированы данные по основным методам моделирования острой ишемии головного мозга (ОИГМ), представлена их классификация, анализируются данные о преимуществах и недостатках той или иной модели. Обсуждаются результаты экспериментальных исследований по изучению патогенеза ОИГМ с использованием различных моделей (полной и неполной глобальной, локальной и мультифокальной ишемии) и способов их реализации (перевязка артерий, клипирование, коагуляция, эмболизация и др.). Особое внимание уделяется «стабильности» последствий острого нарушения мозгового кровообращения: необратимых ишемических повреждений головного мозга или обратимых с реперфузией заданной продолжительности. Отмечается, что важное значение в этих исследованиях должно принадлежать современным методам прижизненной визуализации очагов острого ишемического повреждения, что позволяет оценивать динамику патологического процесса. Предлагаемый метод отвечает требованиям гуманного обращения с животными. Подчеркивается, что выбор релевантной модели ОИГМ определяется задачами предстоящего исследования и технологическими ресурсами научной лаборатории. Development of experimental models for acute forms of cerebrovascular diseases is essential for implementation of methods for their prevention and treatment. One of the principal requirements to such models is their maximum approximation to actual clinical practice. This review systematized major models of acute cerebral ischemia (ACI), their classification, and presented information about their advantages and shortcomings. Also, the review presented results of experimental studies on pathophysiological mechanisms of different types of modeled ACI (complete and incomplete global, local, and multifocal ischemia) and methods for creating these models (arterial ligation, clipping, coagulation, embolization, etc.). Particular attention was paid to “stability” of the consequences of acutely impaired cerebral circulation - an irreversible ischemic brain injury or a reversible injury with reperfusion of a given duration. The authors emphasized that in such studies, a special significance should be given to intravital imaging of acute ischemic damage foci using modern methods, which allow assessing the dynamics of the pathological process and meet the requirements to humane treatment of animals. The choice of a relevant ACI model is determined by objectives of the planned study and the technological resources available at the research laboratory.

ADOLESCENTS IN CRIMINAL STREET GROUPINGS: REASONS AND MOTIVATIONS

2019 ◽  
Vol 29 (2) ◽  
pp. 195-199
Author(s):  
E.O. Chernova
Keyword(s):  
At Risk ◽  
Preventive Measures ◽  
Experimental Studies ◽  
Motivational Factors ◽  
Social Motives ◽  
Factors Affecting ◽  
Social Communities ◽  
Criminal Groups

The article gives an analysis of the results of authorial experimental studies. Motivational factors affecting adolescents' participation in criminal groups are considered, they are: dominant groups of motives, the predominance of aspiration to success or avoidance of failures. Thus, the author explores the subjective potential of the personality of adolescent groupers. According to the results of the research, the author concludes that the specificity of the motivation of such adolescents consists in the predominance of material motives, social motives (involvement in social communities, groupings) and motives of recognition and respect. The author notes that the motivation for avoiding failures is more characteristic of such adolescents than the motivation for the pursuit of success. It is concluded that the data obtained can serve as a basis for developing preventive measures when working with adolescents at risk.

The methodology of experimental research of the feed components extrusion process in order to improve its energy performance

2020 ◽  
pp. 147-152
Author(s):  
E. M. Ratnikov ◽  
D. O. Milko
Keyword(s):  
Experimental Studies ◽  
Energy Performance ◽  
Extrusion Process ◽  
Mathematical Methods ◽  
Screw Extruder ◽  
Mathematical Planning ◽  
Factors Affecting ◽  
Extrusion Processing ◽  
Definition Of

Annotation Purpose. Development of a program and methods for conducting experimental studies of the extrusion process with the definition of parameters and modes of operation of the extruder to improve its energy performance. Methods. Methods of mathematical statistics, synthesis, analysis, description and modeling were used. Results. The application of mathematical methods, in particular mathematical planning, reduces the number of experiments several times, and allows to evaluate the role of influencing factors, obtain a mathematical model of the process and determine the optimal conditions for its parameters and modes, etc. Conclusions. The methodology for experimental studies of a screw extruder is presented with the necessary equipment and methodology for processing the obtained experimental data. A mathematical method of planning, which reduces the number of experiments several times, allows us to evaluate the role of factors affecting productivity and energy intensity is presented. Keywords: extruder, auger, nutrients, research methodology, extrusion, processing, feed.

scholarly journals SURG-22. CUSHING’S DISEASE: A DIFFICULT TO TREAT NEURO-ONCOLOGICAL CONDITION

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi244-vi244
Author(s):  
Santanu Bora ◽  
Ashish Suri
Keyword(s):  
Cortisol Level ◽  
Remission Rate ◽  
Univariate Analysis ◽  
Clinical Manifestations ◽  
Plasma Cortisol Level ◽  
Cushing Disease ◽  
Factors Affecting ◽  
Microscopic Surgery ◽  
Acth Secreting ◽  
Better Than

Abstract BACKGROUND Cushing disease (CD) comprises a spectrum of clinical manifestations secondary to hypercortisolism due to ACTH-secreting pituitary adenoma. Transsphenoidal adenomectomy remains the standard treatment. Because of the significant rate of recurrence or persistence of CD, it is of interest to determine factors that may correlate with long-term outcomes following surgical intervention. OBJECTIVE The objective of our study is to determine the remission rate after surgery with special emphasis on factors affecting remission. METHODS Data of all patients undergoing surgery for CD from 2009 to 2017 was analyzed retrospectively. Transphenoidal resection was the preferred treatment with a recent trend in favor of endonasal endoscopic skull base approach. Post-operative cortisol level of < 2 μg/dL was taken as remission and value between 2 and 5 μg/dL as possible remission. RESULTS 104 patients operated primarily for CD were included for analysis. 47 patients underwent microscopic surgery, 55 endoscopic surgery and two were operated trans-cranially. Remission was achieved in 76.47% of patients. In univariate analysis, factors significantly associated with remission were (1) type of surgery (p=0.01); endoscopy (88.23% remission) better than microscopy (56.6% remission) (2) postoperative day-1 morning cortisol (p=0.004) and; (3) postoperative day-1 morning ACTH (p=0.015). In multivariate analysis, however only postoperative day-1 cortisol was found to be significant as predictor of remission (p=0.02). CONCLUSION Postoperative plasma cortisol level is a strong independent predictor of remission and value less than 10.7µgm/dl can be taken as cut off for predicting remission. Remission provided by endoscopy appears to be significantly better than microscopic approach.

scholarly journals The Nephroprotective Properties of Extracellular Vesicles in Experimental Models of Chronic Kidney Disease: a Systematic Review

2021 ◽  
Author(s):  
Natalia Nowak ◽  
Masayuki Yamanouchi ◽  
Eiichiro Satake
Keyword(s):  
Systematic Review ◽  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Interstitial Fibrosis ◽  
Cell Damage ◽  
Meta Analysis ◽  
Experimental Studies ◽  
Extracellular Vesicle ◽  
Experimental Models ◽  
Preclinical Research

AbstractExtracellular vesicle (EV)-based therapy was hypothesized as a promising regenerative approach which has led to intensive research of EVs in various pathologies. In this study, we performed a comprehensive systematic review of the current experimental evidence regarding the protective properties of EVs in chronic kidney disease (CKD). We evaluated the EV-based experiments, EV characteristics, and effector molecules with their involvement in CKD pathways. Including all animal records with available creatinine or urea data, we performed a stratified univariable meta-analysis to assess the determinants of EV-based therapy effectiveness. We identified 35 interventional studies that assessed nephroprotective role of EVs and catalogued them according to their involvement in CKD mechanism. Systematic assessment of these studies suggested that EVs had consistently improved glomerulosclerosis, interstitial fibrosis, and cell damage, among different CKD models. Moreover, EV-based therapy reduced the progression of renal decline in CKD. The stratified analyses showed that the disease model, administered dose, and time of therapeutic intervention were potential predictors of therapeutic efficacy. Together, EV therapy is a promising approach for CKD progression in experimental studies. Further standardisation of EV-methods, continuous improvement of the study quality, and better understanding of the determinants of EV effectiveness will facilitate preclinical research, and may help development of clinical trials in people with CKD. Graphical Abstract

scholarly journals Upregulation of the Renin–Angiotensin System Pathways and SARS-CoV-2 Infection: The Rationale for the Administration of Zinc-Chelating Agents in COVID-19 Patients

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 506
Author(s):  
Loris Zamai
Keyword(s):  
Chelating Agents ◽  
Ethylenediaminetetraacetic Acid ◽  
Current Knowledge ◽  
Clinical Manifestations ◽  
Renin Angiotensin System ◽  
Experimental Models ◽  
Zinc Metalloprotease ◽  
Previous Hypothesis ◽  
Zinc Metalloproteases

The article describes the rationale for the administration of zinc-chelating agents in COVID-19 patients. In a previous work I have highlighted that the binding of the SARS-CoV spike proteins to the zinc-metalloprotease ACE2 has been shown to induce ACE2 shedding by activating the zinc-metalloprotease ADAM17, which ultimately leads to systemic upregulation of ACE2 activity. Moreover, based on experimental models, it was also shown the detrimental effect of the excessive systemic activity of ACE2 through its downstream pathways, which leads to “clinical” manifestations resembling COVID-19. In this regard, strong upregulation of circulating ACE2 activity was recently reported in COVID-19 patients, thus supporting the previous hypothesis that COVID-19 may derive from upregulation of ACE2 activity. Based on this, a reasonable hypothesis of using inhibitors that curb the upregulation of both ACE2 and ADAM17 zinc-metalloprotease activities and consequent positive feedback-loops (initially triggered by SARS-CoV-2 and subsequently sustained independently on viral trigger) is proposed as therapy for COVID-19. In particular, zinc-chelating agents such as citrate and ethylenediaminetetraacetic acid (EDTA) alone or in combination are expected to act in protecting from COVID-19 at different levels thanks to their both anticoagulant properties and inhibitory activity on zinc-metalloproteases. Several arguments are presented in support of this hypothesis and based on the current knowledge of both beneficial/harmful effects and cost/effectiveness, the use of chelating agents in the prevention and therapy of COVID-19 is proposed. In this regard, clinical trials (currently absent) employing citrate/EDTA in COVID-19 are urgently needed in order to shed more light on the efficacy of zinc chelators against SARS-CoV-2 infection in vivo.

scholarly journals CD4+ CD25+ Foxp3+ Regulatory T Cells, Dendritic Cells, and Circulating Cytokines in Uncomplicated Malaria: Do Different Parasite Species Elicit Similar Host Responses?

2010 ◽  
Vol 78 (11) ◽  
pp. 4763-4772 ◽  
Author(s):  
Raquel M. Gonçalves ◽  
Karina C. Salmazi ◽  
Bianca A. N. Santos ◽  
Melissa S. Bastos ◽  
Sandra C. Rocha ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Parasite Species ◽  
Inflammatory Responses ◽  
Clinical Symptoms ◽  
Clinical Manifestations ◽  
Surface Expression ◽  
Interleukin 10 ◽  
Treg Cells ◽  
Experimental Models ◽  
Necrosis Factor Alpha

ABSTRACT Clearing blood-stage malaria parasites without inducing major host pathology requires a finely tuned balance between pro- and anti-inflammatory responses. The interplay between regulatory T (Treg) cells and dendritic cells (DCs) is one of the key determinants of this balance. Although experimental models have revealed various patterns of Treg cell expansion, DC maturation, and cytokine production according to the infecting malaria parasite species, no studies have compared all of these parameters in human infections with Plasmodium falciparum and P. vivax in the same setting of endemicity. Here we show that during uncomplicated acute malaria, both species induced a significant expansion of CD4+ CD25+ Foxp3+ Treg cells expressing the key immunomodulatory molecule CTLA-4 and a significant increase in the proportion of DCs that were plasmacytoid (CD123+), with a decrease in the myeloid/plasmacytoid DC ratio. These changes were proportional to parasite loads but correlated neither with the intensity of clinical symptoms nor with circulating cytokine levels. One-third of P. vivax-infected patients, but no P. falciparum-infected subjects, showed impaired maturation of circulating DCs, with low surface expression of CD86. Although vivax malaria patients overall had a less inflammatory cytokine response, with a higher interleukin-10 (IL-10)/tumor necrosis factor alpha (TNF-α) ratio, this finding did not translate to milder clinical manifestations than those of falciparum malaria patients. We discuss the potential implications of these findings for species-specific pathogenesis and long-lasting protective immunity to malaria.

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