scholarly journals Controversial Issues of Clinical Immunology. Modern Concepts about the Pathogenesis of Infections

Author(s):  
Zemskov, V.M. ◽  
Zemskov A.M. ◽  
Pronko, K.N. ◽  
Afanasiev, S.S. ◽  
Zemskova, V.A. ◽  
...  

It is postulated that a suppressed or stimulated state of immune reactivity plays an important role in the induction of an infection process, which triggers the activation of microbiota pathogens. Infection-driven destruction of cells of a macroorganism promotes the release of endogenous low molecular weight nucleic acids, mostly RNA, which, within the first hours/days, are responsible for the stimulation of replication and toxin formation by microflora with subsequent disease exacerbation, and as a result, in a few days, cause an increase in antigenicity, immunogenicity, antibiotic susceptibility of pathogens, and activation of nonspecific and specific resistance of the body, with the resulting immune activation. Concurrently with these processes, the intensification of free-radical lipid and protein oxidation is observed, with the formation of immunosuppressive compounds which are neutralized by enzymatic and nonenzymatic factors of the antioxidant system. Thus, in infection processes homeostasis is achieved by means of a sequential cascade of microbial, immune, and metabolic mechanisms which induce, stimulate, and inhibit the responsiveness of the body.

Author(s):  
А.С. Казицкая ◽  
Т.К. Ядыкина ◽  
М.С. Бугаева ◽  
А.Г. Жукова ◽  
Н.Н. Михайлова ◽  
...  

В условиях непрерывного воздействия неблагоприятных факторов окружающей и производственной среды на человека особую актуальность приобретает изучение механизмов, поддерживающих гомеостаз организма. Длительное поступление фторидов в организм приводит к формированию хронической фтористой интоксикации, патогенез которой вызывает многочисленные споры и дискуссии. До сих пор недостаточно внимания уделяется изучению висцеральной патологии, обусловленной нарушениями иммунного статуса в условиях воздействия на организм соединений фтора. Практически отсутствуют исследования по изучению иммунной реактивности, определяющей морфофункциональный характер ответной реакции печени на ранних стадиях развития фтористой интоксикации. Цель работы - изучение действий патофизиологических механизмов иммунной реактивности печени при субхроническом действии на организм соединений фтора. Методика. Опыты проведены на 210 лабораторных крысах-самцах массой 180-220 г., разделенных на 2 группы: контрольную (n=80) и группу животных с субхроническим действием фторида натрия (n=130). Экспериментальные животные в течение 12 нед имели свободный доступ к водному раствору фторида натрия (концентрация 10 мг/л, что составляет суточную дозу фтора 1,2 мг/кг массы тела). Для изучения иммунологических и биохимических показателей забирали кровь из хвостовой вены через 1, 3, 6, 9, 12 нед от начала эксперимента. Для оценки состояния гуморального звена иммунитета определяли уровень сывороточных иммуноглобулинов (IgA, IgG, IgM) иммуноферментным анализом с помощью наборов реактивов ЗАО «Вектор-Бест» (Новосибирск). Уровень сывороточных цитокинов: TNF-α, IL-1β, 2, 4, 6, 10 определяли на анализаторе Multiskan EX методом иммуноферментного анализа с использованием наборов «Вектор Бест» (Новосибирск). Подсчет общего количества лейкоцитов произведен классическим способом в камере Горяева, анализ лейкоцитарной формулы - в окрашенных мазках периферической крови. Метаболические изменения оценивали по активности ферментов в ткани печени: щелочной фосфатазы (ЩФ), аланин- и аспартатаминотрансфераз (АЛТ, АСТ), лактатдегидрогеназы (ЛДГ), гаммаглутамилтранспептидазы (γ-ГТ). Активность ферментов определяли унифицированными методами с помощью наборов реактивов ЗАО «Вектор-Бест» (Новосибирск) на фотометре PM-750 (Германия). Гистологические исследования печени осуществляли после декапитации крыс, проводимой под эфирным наркозом. Результаты. Показано, что субхроническое воздействие фторида натрия сопровождается формированием внутриклеточных и внутрисосудистых повреждений печени. Активация медиаторов воспаления и развитие иммунологических нарушений в динамике эксперимента способствуют формированию системной воспалительной реакции, которая приводит к появлению стойких морфологических нарушений в печени и изменению активности ферментов основных метаболических путей. Заключение. Полученные результаты могут быть использованы при разработке и проведении профилактических мероприятий в условиях воздействия на организм высоких концентраций фтора с последовательным применением детоксикационной, иммуномодуляторной и органопротекторной коррекции. Studying mechanisms, which maintain the body homeostasis, is particularly important in the conditions of continuous impact of adverse environmental and manufacturing factors. Long-term exposure to fluorides leads to chronic fluoric intoxication, the pathogenesis of which is a subject of multiple controversy and discussions. Not enough attention is still paid to elucidating the visceral pathology associated with fluorine-induced immune disorders. There are virtually no studies of immune reactions that define the morphofunctional nature of the liver response to early stages of fluoric intoxication. Aim. To study pathophysiological mechanisms of hepatic immune reactivity in subchronic exposure of the body to fluorine compounds. Methods. Experiments were performed on 210 male rats weighing 180-220 g. The animals were divided into two groups: 1) control (n=80) and 2) subchronic exposure to sodium fluoride (n=130). The rats had free access to a 10 mg/l aqueous solution of sodium fluoride (daily dose, 1.2 mg/kg body weight) for 12 weeks. Blood was withdrawn from the caudal vein at 1, 3, 6, 9, and 12 weeks of the experiment for immunological and biochemical tests. Histological study of the liver was performed after decapitation of rats under ether anesthesia. Results. The subchronic exposure to sodium fluoride was associated with intracellular and intravascular damage of the liver. Activation of inflammatory mediators and development of immunological disorders during the experiment contributed to a systemic inflammatory reaction, which resulted in persistent morphological injuries of the liver and changes in enzyme activities in major metabolic pathways. Conclusion. The study results can be used for development and implementation of preventive measures against the effects of high fluorine concentrations, which would include a successive use of detoxification, immunomodulation and organ protection.


Metabolites ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 14
Author(s):  
Petr G. Lokhov ◽  
Dmitry L. Maslov ◽  
Steven Lichtenberg ◽  
Oxana P. Trifonova ◽  
Elena E. Balashova

A laboratory-developed test (LDT) is a type of in vitro diagnostic test that is developed and used within a single laboratory. The holistic metabolomic LDT integrating the currently available data on human metabolic pathways, changes in the concentrations of low-molecular-weight compounds in the human blood during diseases and other conditions, and their prevalent location in the body was developed. That is, the LDT uses all of the accumulated metabolic data relevant for disease diagnosis and high-resolution mass spectrometry with data processing by in-house software. In this study, the LDT was applied to diagnose early-stage Parkinson’s disease (PD), which currently lacks available laboratory tests. The use of the LDT for blood plasma samples confirmed its ability for such diagnostics with 73% accuracy. The diagnosis was based on relevant data, such as the detection of overrepresented metabolite sets associated with PD and other neurodegenerative diseases. Additionally, the ability of the LDT to detect normal composition of low-molecular-weight compounds in blood was demonstrated, thus providing a definition of healthy at the molecular level. This LDT approach as a screening tool can be used for the further widespread testing for other diseases, since ‘omics’ tests, to which the metabolomic LDT belongs, cover a variety of them.


1998 ◽  
Vol 72 (4) ◽  
pp. 3377-3382 ◽  
Author(s):  
John W. Barrett ◽  
Andy J. Brownwright ◽  
Mark J. Primavera ◽  
Subba Reddy Palli

ABSTRACT A recombinant Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) expressing the green fluorescence protein (GFP) under the control of the AcMNPV polyhedrin promoter was constructed to study the spatial and temporal regulation of baculovirus infection in a permissive host. Larvae that ingested AcMNPV-GFP showed localized expression of GFP in the midgut epithelial cells, as well as hemocytes, at 24 h postinfection. The presence of fluorescence in these tissues indicated not only that the virus was replicating but also that the very late viral proteins were being synthesized. Secondary infection occurred within the tracheal cells throughout the body cavity, confirming earlier reports, and these foci of infection allowed entry of the virus into other tissues, such as the epidermis and the fat body.


2021 ◽  
Vol 6 (5) ◽  
pp. 22-27
Author(s):  
M. M. Mishina ◽  
◽  
O. V. Kotsar ◽  
Pochernina M. H. ◽  
O. V. Kochnieva ◽  
...  

The purpose of the study was to analyze modern literature on the problems of dysbiosis in patients with COVID-19, to study the main mechanisms of systemic interaction between the intestine and lungs, as well as changes in the microbiota that occur under the influence of coronavirus infection. Materials and methods. A comprehensive selection of research methods was used for the work: systematization of the material, the method of generalization, methods of analysis and synthesis. Scientific works in the field of microbiology, epidemiology and infectious diseases were studied. Literature data for the last 2 years (2019-2021) were considered. The results of bacteriological studies from patients with COVID infection were described. The data obtained were processed using information-analytical and statistical-analytical methods. Results and discussion. As a result of this work, a complex of connections between intestine and lungs, which is called the "intestinal-lung axis", was considered. It is known that the interaction between these two biotopes occurs with the participation of microflora and its metabolites. Dysfunction of the intestinal barrier is accompanied by bacterial translocation. Bacteria from the intestinal lumen enter the liver through the portal vein system. The lymphatic pathway of bacterial translocation from the intestine to the lungs is also possible, which causes multiple organ failure syndrome in coronavirus infection. The COVID-19 virus is able to reduce the number of ACE2 receptors in the gastrointestinal tract, which leads to an imbalance in the intestines. At the same time, the infection process in the lungs promotes the growth of bacteria of the Enterobacteriacae family in the intestine, which also leads to dysbiotic disorders. The use of probiotics is an effective tool in the complex treatment of this infection, which facilitates the general condition of patients. In the course of treatment, it is important not only to eliminate the virus from the body, but also to restore normal intestinal microbiota after an infection. Conclusion. Thus, the use of probiotic drugs for the treatment of patients with coronavirus infection can significantly reduce the risk of developing dysbiosis and improve the condition of patients. A perspective direction is the development of new treatment regimens for dysbiotic conditions using probiotics, eubiotics, synbiotics and postbiotics to prevent the development of severe complications in COVID infection


2018 ◽  
Author(s):  
Jianyu Li ◽  
Mengzhu Shi ◽  
Yuechao He ◽  
Jianwei Fu ◽  
Lizhen Zheng

Background. Phyllotreta striolata is a worldwide pest that harms cruciferous vegetables. The use of pathogenic microorganisms to control pests is an important means of biological control. Using pathogenic microorganisms to prevent and control P. striolata has rarely been reported. Methods. In this study, the infection process of a Metarhizium strain highly pathogenic to P. striolata was observed by stereomicroscopyand scanning electron microscopy (SEM). Results.The results showed that the attachment of Metarhizium strain Ma6 to the body surface varied; the conidia distribution was greatest in the tibia of the posterior leg with thick bristles and in the intersegmental abdominal membrane, and the spore distribution occurred least in the smooth and hard portions of the insect’s body. At the start of the infection, Metarhizium strain Ma6 generally grew from the body parts with gaps or connecting spaces such as mouthparts and the thoracic leg base and joints, then the spores germinated with germ tubes and penetration peg, and the penetration peg penetrated the body surface. Ten days after inoculation, the mycelia divided into conidia, and many mycelia and spores covered the entire adult insect’s body. Discussion. Spore germination occurred on the 5th day after inoculation, and many hyphae and spores covered the entire adult insect body within 10 days after inoculation. And the invasion into tissue gaps from the weaker areas is more efficient than intruding from the body hard surface. This may be the reason for the Metarhizium strain Ma6’s high virulence. This study preliminarily clarified the infection ability and invasion approach of a Metarhizium strain against P. striolata, providing evidence for evaluating the strain’s insecticidal effect and application prospect.


2020 ◽  
Vol 26 (3) ◽  
pp. 78-82
Author(s):  
Т. F. Golubova ◽  
А. I. Kreslov

Climate is an active, powerful factor that can have a powerful therapeutic effect. Climatotherapy is prescribed for the purpose of General strengthening effects on the body, to stimulate its defenses, increase non-specific resistance, especially in chronic or sluggish pathological processes. The effect of climate therapy is manifested in the body's responses to environmental factors, the main condition of which is the use of physiologically based methods of dosing climate procedures. The bioclimatic station (BCS) of the resort of Yevpatoria carries out meteorological observations of medical orientation and their dosing. The creation of a modern center of climatotherapy, as a scientific-clinical Department of medical climatology on the basis of the BCS will allow to organize a single service on introduction of modern methods of climatotherapy in Evpatoria and the Republic of Crimea, improve the quality of the holiday of climateprotection and effectiveness of climatotherapy.


2020 ◽  
Vol 10 (5) ◽  
pp. 67-72 ◽  
Author(s):  
Zlata V. Davydova ◽  
Oraz D. Yagmurov

The article presents modern data on pathomorphological changesin lung tissue formed under the influence of acute and chronic intoxication with ethanol and its metabolites. At autopsy of the persons abusing alcohol, along with defeat ofabrain, heart, a liver note considerable changes in lungs. It was found that ethanol is excreted by the lungs and kidneys unchanged. The lungs are actively involved in the conversion of ethanol into carbon dioxide. The toxic effect ofethanol and its metabolites increases the permeability of the vascular wall, which leads to the accumulation of protein in the lung tissue with the development of pronounced dystrophic and destructive changes with the formation ofsubsequent pneumosclerosis. Alcohol negatively affects the function of alveolar macrophages, which have an important role inprotecting the lungs. Under the influence of ethanol in macrophages, biochemical processes are slowed down, expressed in a sharp decrease in their phagocytic activity and ability to move. In turn, it is necessary to note the studies that reflect the data on the influence of alcohol on the lung surfactant, which stabilizes the surface tension in the alveoli and counteracts the transudation of fluid into the alveoli. Alcohol adversely affects the phospholipids included in the surfactant and disrupts the process of its formation. Alcohol intoxication is the cause of 60% of comatose States, and obturation-aspiration complications are the leading form of respiratory disorders. Alcohol-induced disorders of the mucociliary apparatus contribute to the ingress of foreign particles into the respiratory tract. The defeat of these protective mechanisms in combination with a decrease in the overall immune reactivity of the body cause the development of anumber of pathological changes in the lungs. Thus, the study of morphological features of lung injuries in acute ethanol poisoning is of fundamental importance in elucidating the links of pathogenesis ofterminal States, their justified therapy.


2000 ◽  
Vol 90 (7) ◽  
pp. 699-709 ◽  
Author(s):  
Bryan A. Bailey ◽  
Patricia C. Apel-Birkhold ◽  
Nichole R. O'Neill ◽  
James Plaskowitz ◽  
Sharon Alavi ◽  
...  

Two pathogenic fungi of opium poppy, Pleospora papaveracea and Dendryphion penicillatum, were isolated from field material in Beltsville, MD. The processes of infection by these two fungi were studied to determine the optimal environmental conditions for infection. Both fungi formed appressoria capable of penetrating directly through the plant epidermal layer. Of the two fungi, P. papaveracea was more aggressive, causing more rapid necrosis. Appressorial formation by P. papaveracea occurred as early as 4 h after application of a conidial suspension to poppy leaves. P. papaveracea formed more appressoria than did D. penicillatum, especially at cool temperatures (7 to 13°C). In greenhouse studies, P. papaveracea caused more damage to opium poppy than did D. penicillatum when applied in 10% unrefined corn oil. In the field, P. papaveracea was more consistent in its effects on opium poppy from a local seed source designated Indian Grocery. P. papaveracea caused higher disease ratings, more stem lesions, and equal or greater yield losses than did D. penicillatum on Indian Grocery. The late-maturing opium poppy variety White Cloud was severely damaged by disease, regardless of formulation or fungal treatment. P. papaveracea was the predominant fungus isolated from poppy seed capsules and the only fungus reisolated from the field the following year. These studies provide a better understanding of the infection process and the differences between these two pathogenic fungi and will be beneficial for the development of the fungi as biological control agents.


The main events and circumstances of human evolution are considered: classification of hominids, first descriptions, localization, chronology; artifacts characterizing their material and cultural activities; modern reconstruction of lifestyle and resettlement; and modern theories explaining the structural features of hominids and the processes of their occurrence. The manifestations of intelligent activity are discussed, in particular, their dependence from the structure of the body, the size, and complexity of the brain, for which comparisons with various animals are made. Particular attention is paid to unresolved or controversial issues. This material is necessary to assess the possibilities of the self-organization of complex systems theory (second chapter): if it adequately models the characteristics of a human's origin, then it can be used to understand the evolution of human mind and in the subsequent period, up to the current state.


Author(s):  
Bronwyn Lok ◽  
Mowaffaq Adam Ahmad Adam ◽  
Laina Zarisa Mohd Kamal ◽  
Nwakpa Anthony Chukwudi ◽  
Rosline Sandai ◽  
...  

Abstract Candida albicans is a commensal yeast commonly found on the skin and in the body. However, in immunocompromised individuals, the fungi could cause local and systemic infections. The carbon source available plays an important role in the establishment of C. albicans infections. The fungi's ability to assimilate a variety of carbon sources plays a vital role in its colonization, and by extension, its fitness and pathogenicity, as it often inhabits niches that are glucose-limited but rich in alternative carbon sources. A difference in carbon sources affect the growth and mating of C. albicans, which contributes to its pathogenicity as proliferation helps the fungi colonize its environment. The carbon source also affects its metabolism and signaling pathways, which are integral parts of the fungi's fitness and pathogenicity. As a big percentage of the carbon assimilated by C. albicans goes to cell wall biogenesis, the availability of different carbon sources will result in cell walls with variations in rigidity, adhesion, and surface hydrophobicity. In addition to the biofilm formation of the fungi, the carbon source also influences whether the fungi grow in yeast- or mycelial-form. Both forms play different roles in C. albicans’s infection process. A better understanding of the role of the carbon sources in C. albicans’s pathogenicity would contribute to more effective treatment solutions for fungal infections.


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