Point-of-care diagnosis of COVID-19 disease based on antigen tests.

AIMS: This review is focused on the laboratory diagnoses of the coronavirus disease 2019 (COVID-19) by recognizing the antigen of the causative agent SARS-CoV-2 virus. Various antigen tests are available in this moment and these tests are being further developed in order to reach a better diagnostic value. The issue is reviewed in a complex view. METHODS: In this work, a complex survey of the current literature was made. The relevant and recent papers related to antigen tests of COVID-19 are discussed and cited. Basic specifications of the antigen tests and competitive methods were also scrutinized in the current literature. RESULTS: The survey of the current literature (years 2019 ‒ 2021) was made and diagnostic methods like lateral flow tests (lateral flow immunochromatographic assay) and various types of biosensors were specified as tools for COVID-19 diagnosis and their application to be used as a point-of-care test is considered. CONCLUSIONS: Small hand-held assays applicable in the point-of-care conditions for diagnosis of COVID-19 by analysis of SARS-CoV-2 antigen are the means of a growing interest and these means undergo a significant development leading to the improvements of their specifications and applicability to the current praxis. Merit of the assays is discussed in this paper (Tab. 3, Fig. 2, Ref. 109).

COVID-19 molecular level laboratory diagnoses.

AbstractAIMS: Aims: The Coronavirus Disease 2019 (COVID-19) caused not only global pandemic, but it also pointed at unprepared health care systems and countermeasures were introduced under the pressure of urgent circumstances. This review is focused on discussion and critical evaluation of instrumental tools for COVID-19 diagnosis that were developed in the last months. METHODS: Survey of actual literature and scientific reports was made. The most substantial analytical and diagnostical methods were identified and described. Principles and limitations of the methods are described, and actual papers are cited in this review. RESULTS: Analytical and diagnostical methods like Polymerase Chain Reaction (PCR), Loop-mediated isothermal Amplification (LAMP), Lateral Flow Immunochromatography Assay (LFIA), Enzyme-Linked Immunosorbent Assay (ELISA), biosensors and ChemiLuminescence ImmunoAssay (CLIA) are discussed for assay of viral particles, antigens and specific host antibodies in blood, serum, plasma, nasopharyngeal swab and other samples in order to diagnose COVID-19. CONCLUSIONS: The Coronavirus Disease 2019 (COVID-19) is an emerging disease that has spread over the world since the end of year 2019. The global epidemic pointed at the necessity to introduce sensitive methods for instrumental diagnosis of COVID-19 and distinguishing it from the other viral diseases. (Tab. 2, Ref. 96).

Bacillus anthracis as a biological warfare agent: infection, diagnosis and countermeasures.

AIM: Bacillus anthracis is a causative agent of zoonotic anthrax disease. In the last years, significant progress in therapy and diagnosis of anthrax was made. Concurrently, knowledge about anthrax progression, molecular pathology and release of anthrax toxin during the disease has improved. This review covers the recent progress in this field. METHODS: In this review, specifications of B. anthracis, anthrax disease, medical and biomedical countermeasures and diagnostic tools were surveyed. The actual literature was summarized and relevance of the microorganism as a biological warfare agent and the ways how to reduce its impact including therapeutic protocols were written and discussed. RESULTS: Currently, the microorganism is considered one of the top biological warfare agents due to lethality, long term stability of spores, easy dissemination and production. The recent research is focused on countermeasures suitable for reduction of consequences by a misuse of the microorganism in form of biological weapon (Tab. 3, Fig. 1, Ref. 101). Text in PDF www.elis.sk.

Copper and copper nanoparticles toxicity and their impact on basic functions in the body.

Copper is a biogenic metal having multiple functions in basic processes in organisms and it is common in all kingdoms of life. Limited intake of copper is a problem; however, doses of copper exceeding the recommended alimentary source are problematic as well and toxicity is soon manifested. Impact of copper nanoparticles on human health is another serious issue taken into consideration in this review. Regarding to copper toxicity, neurodegenerative disorders including Alzheimer and Parkinson diseases are suspected to be linked to copper toxicity or copper can contribute to their progression. Wilson and Menke diseases are also described as examples of copper intolerance. This paper is focused on the description, literature survey and discussion of the current knowledge about copper and copper nanoparticles toxicity and their involvement in various pathological processes (Tab. 6, Fig. 2, Ref. 171). Keywords: reactive oxygen species; Alzheimer disease; acetylcholinesterase; copper; Fenton reaction; disorder; heavy metal; pollution; nanoparticle.

Oxidative stress in Alzheimer disease as a target for therapy.

In the recent time, neurodegenerative disorders like Alzheimer disease were recognized for their significant role in the current healthcare because of their growing incidence and costs for health insurance systems. Effective therapy is missing and even etiology of the diseases like Alzheimer disease is not deeply known. In the case of Alzheimer disease, it is probable that oxidative stress is at least a factor involved in the disease. Nevertheless, the current literature is controversial and ambiguous in this matter. This review is focused on mapping the role of oxidative stress as well as on a consideration that oxidative stress represents the pathway at which a therapeutic strategy can be aimed. This paper provides a survey of contemporary literature on oxidative stress in Alzheimer disease and discusses the opportunities for establishing a therapy based on interfering the stress (Fig. 5, Ref. 117).

Galantamine has impact on immunity in mice exposed to keyhole limpet hemocyanin.

OBJECTIVES: In this work, we hypothesized whether galantamine could interact with the cholinergic anti-inflammatory pathway and modulate immunity this way. BACKGROUND: Galantamine is a drug used for the therapy of Alzheimer disease. The drug inhibits enzyme acetylcholinesterase in the central nervous system, which causes better availability of neurotransmitter acetylcholine. METHODS: In the experiment, we immunized BALB/c laboratory mice by keyhole limpet hemocyanin (KLH) in combination with galantamine in a dose 0.02-0.5 mg/kg. The animals were sacrificed from 1 to 7 days after the substances applications and plasma was collected in order to examine immunochemical markers by enzyme-linked immunosorbent assay. RESULTS: We found significant drop in production of immunoglobulins and interleukin (IL) 4 level while IL2, IL4 and tumour necrosis factor α remained unaltered for the whole experiment. We infer that galantamine causes better availability of acetylcholine also in blood system, where the neurotransmitter interacts with nicotinic acetylcholine receptors on macrophages and initiates cholinergic anti-inflammatory pathway. CONCLUSIONS: In a conclusion, galantamine can cause lower efficacy of vaccination or immunity response to an infectious disease and the phenomenon should be taken into consideration in the current therapy (Tab. 1, Fig. 2, Ref. 24).

Freund´s complete adjuvant effect on BALB/c mice: an insight into inflammation and oxidative stress after immunity challenge.

Freund´s complete adjuvant (FCA) is a mean used for improving immunization efficacy in experiments and veterinary medicine. Despite high efficacy, it is not used in human vaccination due to number of adverse effects. Arthritis can be an example of a typical adverse consequence. In this work, we decided to investigate the link between oxidative stress and inflammation in animals exposed to FCA. BALB/c mice received either saline or FCA in doses 10-50 µl and were euthanized from one to three days after infection. Interleukins (IL) IL-2, IL-4 and tumor necrosis factor α (TNF-α) were determined in plasma. Ferric reducing antioxidant power (FRAP), malondialdehyde by thiobarbituric acid reactive substances assay (TBARS), reduced glutathione (GSH) and caspase-3 were measured in livers, muscles and other organs. We determined significant effect of FCA on TBARS and GSH in the livers. Beside this, TBARS were altered in muscles as well. Inflammation was confirmed by increased level of TNF-α. Taking the results into account, we infer that the harmful effect of FCA is mediated not only by inflammation but also by oxidative. This should be considered when pathological consequences of FCA are scored.

The perspective of caffeine and caffeine derived compounds in therapy.

Caffeine (1,3,7-trimethylxanthine) is a plant secondary metabolite with a significant impact on multiple processes and regulatory pathways in the body. Though major part of the population meets caffeine via coffee, tea or chocolate, it has also an important role in pharmacology and it is used as a supplementary substance in medicaments. Currently, the ability of caffeine to ameliorate some neurodegenerative disorders is proved in some studies. This review describes basic data about caffeine including toxicity, pharmacokinetics, biological mechanism of the action, and metabolism. Beside this, promising applications of caffeine, new medicaments and derivatives are discussed. Relevant papers and inventions are depicted in the manuscript. Caffeine is a pharmacologically promising substance that deserves big consideration in the current research and development. The compound has several reasons to be an object of scientific interest and to be used for pharmacology purposes. Despite an extensive research for a long time, no significantly negative effects on human health were proved hence caffeine can be considered as a completely safe compound. The recent data about amelioration of neurodegenerative and other disorders are promising and deserving more work on the issue. ARTICLE HIGHLIGHTS: Caffeine is a purine alkaloid from plants and it has a broad use in current pharmacology. Caffeine is a competitive antagonist of neurotransmitter adenosine on adenosine receptors. The substance is added as a supplementary to drugs and food.Besides interfering on adenosine receptors, caffeine interacts with acetylcholinesterase, monoamine oxidase, phosphodiesterase, ryanodine receptors and others.Current research is devoted to the role of caffeine in neurodegenerative diseases and immunity alteration. New chemical compounds based on caffeine moiety are prepared (Tab. 4, Fig. 6, Ref. 149).

Caffeine alters oxidative homeostasis in the body of BALB/c mice.

Caffeine is a metabolite from coffee genus and some other plants. It has disparate molecular targets in the body. Beside the major action based on antagonism on adenosine receptor, it is involved in other neurotransmission pathways as well. The complete mechanism of caffeine action remains unrevealed including link to oxidative homeostasis. For the reason, the current paper solves how caffeine influences oxidative homeostasis in BALB/c mouse model. Caffeine was given intramuscularly in doses 1-64 mg/kg and the animals were sacrificed in time intervals from 4 hours up to 3 days. In the experiment, a significant increase of thiobarbituric acid reactive substances (TBARS) levels in the kidney and decrease in the brain indicated up and down regulation of oxidative burden. Ferric reducing antioxidant power (FRAP) level in the kidney appoint at release of low molecular weight antioxidants in the organ. The remaining organs including heart, muscles and liver were intact. In the same way, caspase 3 level was steady and no apoptotic processes were proved (Fig. 3, Ref. 48).

Butyrylcholinesterase as a biochemical marker.

Butyrylcholinesterase (BChE) is an enzyme expressed in multiple organs and abundant in plasma. BChE can fluctuate in course of several reasons while both hypercholiensterasemia and hypocholinesterasemia are known. Considering evidence of BChE activity alterations, hepatocellular carcinoma, chronic liver diseases and poisoning with carbamates or organophosphates can be diagnosed by activity assay. BChE is responsible for detoxification reactions, and the compounds such as cocaine, succinylcholine, and acetylsalicylic acid are degraded in the body. The detoxification can be slowed in patients carrying the K variant of the enzyme. Summarization of literature, discussion on the meaning of BChE in the body, and the principles of BChE assay in samples are described in the review (Tab. 2, Fig. 8, Ref. 86). Text in PDF www.elis.sk.

[New methods increasing assisted reproduction results]. / Nové metody zvysující úspesnost asistované reprodukce.

OBJECTIVE: The brief review of historical development and application of the assisted reproduction methods at our centre and the recent methods increasing the assisted reproduction results. The new mentioned methods are sperm selection before the intracytoplazmatic sperm injection (PICSI = preselected sperm intracytoplasmic injection) and continuous embryo development monitoring. DESIGN: Review article.

Biochemical insight into soman intoxication and treatment with atropine, HI-6, trimedoxime, and K203 in a rat model.

OBJECTIVE: The present experiment is based on biochemical assessment of nerve agent soman intoxication and atropine, respectively atropine and HI-6, trimedoxime or K203 treatment in rats. BACKGROUND: Nerve agents are toxic substances irreversibly inhibiting enzyme acetylcholinesterase (AChE). Treatment is typically based on application of atropine and oxime reactivator. Atropine is able to protect overstimulation of muscarinic acetylcholine receptors. Application of oxime reactivator enable return of AChE activity and full suppression of intoxication. METHODS: In a total, fifteen biochemical markers were assayed in plasma or blood of intoxicated animals. 42 rats were divided into 7 groups each 6 individuals. The first group was exposed to atropine; the second group was exposed to one LD50 of soman and atropine. The groups 3-5 were exposed in a same way as the second group and were treated with oxime reactivators: HI-6 (group 3), trimedoxime (4) and K203 (5). The sixth group was control treated with saline solution only. The last (seventh) group was intoxicated with soman only. RESULTS: The most striking shifts were found for blood acetylcholinesterase and plasma creatinine, glucose, inorganic phosphate as well as uric acid. Lactate dehydrogenase and aspartate aminotransferase assays were useless due to soman interference. CONCLUSION: It was demonstrated that treatment was able to protect poisoned animals from metabolic disorder represented by hyperglycemia and nephropathy represented by hyperuricemia and elevated creatinine. Soman exposure and treatment with the oxime reactivators and/or atropine contains quite complex and still not well understood side mechanisms (Tab. 2, Fig. 1, Ref. 25).

Pralidoxime--the gold standard of acetylcholinesterase reactivators--reactivation in vitro efficacy.

OBJECTIVE: In this work, we aim to summarize the universality of this compound, its reactivation potential when different cholinesterase inhibitors are used. BACKGROUND: Pralidoxime is considered as a gold standard of acetylcholinesterase reactivators--antidotes used in case of nerve agent poisonings. It has been commercially available for many years. However, several studies deem this oxime an old-fashion antidote. METHODS: Pralidoxime was synthesized at our department. The reactivating efficacy was tested on 10% (w/v) rat brain homogenate that had been incubated with appropriate inhibitor for 30 minutes to reach 96% inhibition of AChE. Then, pralidoxime was added for 10 minutes. Measurements were performed at 25 degrees C, pH 8, and 10(-3) and 10(-5) M concentrations of AChE reactivators. The activities of brain AChE were measured by a potentiostatic method. RESULTS: No sufficient reactivation was achieved at the concentration of 10(-5) M, which is a concentration that can be reached after administration of therapeutic doses. At a higher dose (10(-3) M), pralidoxime reactivated AChE inhibited by paraoxon, chlorpyrifos, Russian VX, VX and sarin. CONCLUSION: From the obtained results, it is clear that pralidoxime seems to be a poor reactivator of AChE inhibited by organophosphorous AChE inhibitors and thus cannot be labeled as a universal reactivator (Tab. 1, Fig. 3, Ref. 31).

Piezoelectric immunosensor for the direct and rapid detection of Francisella tularensis.

A novel immunosensing device based on a piezoelectric sensor for direct detection of the biological warfare agent Francisella tularensis was developed. This sensor includes mouse polyclonal antibody immobilized in a layer of protein A covalently linked to the gold electrode of the sensor. The immunosensor is able to detect F. tularensis with the limit of detection 10(5) CFU/mL with a typical measuring cycle > 5 min. The sensor was successfully evaluated for rapid detection of F. tularensis spikes in drinking water and milk; no deterioration of sensitivity in comparison with buffer solutions was observed. The proposed concept of a rapid measurement of microbial agents seems to be promising for evaluation of samples after short pre-cultivation enrichment.

ANALYSIS OF BAROREFLEX FUNCTION BY MEANS OF MATHEMATICAL MODEL.

Re-evaluation of all functions of baroreflex by means of a simple mathematical model of circulation was the aim of the present study. The following states are modelled: 1. Rest. 2. Immediately after baroreceptor denervation. 3. Several days after denervation. 4. Physical exercise before denervation. 5. Physical exercise several days after denervation. Despite the same cardiac contractility and the same vasodilatation in working muscles as before denervation the cardiac output is by one third lower after baroreceptor denervation. In conclusion, a model simulation revealed the common regulation of blood pressure and blood volume by baroreflex and kidneys as a primary function of baroreflex.

CIRCADIAN BLOOD PRESSURE VARIABILITY AND EXERCISE THERAPY.

The objective of this study was to find if there was a relationship between the time when cardiovascular rehabilitation was running in the patients after myocardial infarction and an average daily value of systolic and diastolic blood pressure at 7-day ambulatory blood pressure monitoring.Systolic and diastolic pressures significantly increased in patients who underwent cardiovascular rehabilitation in the morning from 9.00 a.m. to 10.15 a.m., and significantly decreased in those who did their physical exercise in the afternoon from 1.30 p.m. to 2.45 p.m., compared to their blood pressure values on days without rehabilitation.

[Magnetic resonance in urogynecology]. / Vyuzití magnetické rezonance v urogynekologii.

OBJECTIVE: The aim of the study was to review the use of the MRI in urogynaecology and to describe an original method for the construction of 3D computer models of pelvic floor. DESIGN: Pilot study. SETTING: Department of Obstetrics and Gynaecology, Institute of Sexuology, 1st Faculty of Medicine, Charles University, Prague, Department of Radiodiagnostics, Charles University, Hradec Králové. METHODS: A review of the use of the MRI in urogynaecology was made. A new method was introduced for creation of computer 3D models of female pelvis based on the data obtained by the MRI. RESULTS: Five complex computer models of the female pelvic organs and pelvic floor were created. Many so far estimated details were visualized. CONCLUSION: The use of MRI in urogynaecology can bring important data about the functional anatomy of female pelvic floor.

[Importance of regular screening for genital chlamydiosis in adolescents]. / Význam pravidelne opakovaného screeningu genitální chlamydiózy u dospívající mládeze.

OBJECTIVE: Determination of prevalence of genital chlamydiosis in similar group of adolescents as in that examined two years ago. Comparison of the results with the previous ones to confirm positive impact of a repeated screening on drop of prevalence of the infection. Another objective is to make the epidemiological data on genital chlamydiosis in the countries of the "Eastern Block" more accurate, and at the same time to assess the most suitable screening method. DESIGN: Prospective epidemiological study aimed at finding whether the repeated screening examinations of genital chlamydiosis in adolescents will result in decreased incidence of the infection. SETTING: Veterinary Research Institute, Department of Clinical Microbiology of the Faculty Hospital, Regional Hygienic Station, Department of Gynecology and Obstetrics, Medical Faculty, Masaryk University, Brno. METHODS: The groups under testing comprised male and female students of two secondary medical schools and one private grammar school older than 18 (n = 232, of which 33 were boys and 199 girls). Direct detection of C. trachomatis was carried out from the urinary sediment of the sample of morning urine using ligase reaction, polymerase chain reaction, ELISA and direct immunofluorescence. RESULTS: Identical positive result of C. trachomatis detection by four methods was obtained 4 times, i.e. 1.7%. The result of LCR and PCR were positive identically (4 times), ELISA and IF were, besides the above results, positive in other 1 resp. 5 cases. CONCLUSION: Screening examinations of genital chlamydiosis were performed in adolescents in the town of Brno. Morning samples of urine from 232 students of secondary schools were examined on C. trachomatis using the following methods: LCR, PCR, ELISA, and IF. The LCR and PCR were positive 4 times, ELISA 5 times, IF 9 times. Positive results by LCR and PCR were identical. ELISA and IF were positive in other cases. Noninvasive methods are suitable for screening of latent genital chlamydiosis and for estimation of its prevalence. The authors of the study recommend the ligase chain reaction (LCR) as a most suitable screening method.

Antioxidants countermeasures against sulfur mustard.

Sulfur mustard (SM) is a vesicant chemical warfare agent that persists as a serious menace from the viewpoint of acute and chronic toxicity, simple synthesis and no effective treatment currently being available. The two most deleterious basic molecular mechanisms in SM poisoning are: inflammation and over-activation of poly(ADP-ribose) polymerase and the resulting DNA alkylation. Oxidative stress is the common consequence of these pathway activations. In the present review, the significance of oxidative stress in SM poisoning is discussed along with research on antioxidant therapy as a suitable antidote. The temporal dynamics of the redox imbalance, the antioxidant depletion and impact this has on tissues are described as the pathologies induced by SM. Special attention is paid to ameliorating the damage using low molecular weight antioxidants. Melatonin, epigallocatechin gallate and flavone derivatives, in particular, have been studied in recent experiments. The suitability of these antioxidants for therapy purposes is considered in a separate chapter. The review concludes with a view to the future and the studies needed on antioxidant therapy as a countermeasure to SM poisoning.

Ascorbic acid: an old player with a broad impact on body physiology including oxidative stress suppression and immunomodulation: a review.

Ascorbic acid is a low molecular weight antioxidant well known as anti-scorbut acting vitamin C in humans, primates and guinea pigs. This review summarizes basic data about ascorbic acid in its physiological action point of view. It is divided into biochemistry of ascorbic acid synthesis, mechanism of antioxidant action and participation in anabolism, pharmacokinetics and excretion, exogenous ascorbic acid immunomodulatory effect and participation in infectious diseases, impact on irradiation and intoxication pathogenesis, and supplementary demands. The primary intention was to consider ascorbic acid not only as an antioxidant but also as a chemical compound affecting multiple pathways with a potential beneficial impact in many diseases and processes in human body.