Effects of long-term oral administration of silver nanoparticles on the cognitive functions of mammals

2021 ◽  
Vol 29 (6) ◽  
pp. 33-38
Author(s):  
Anna Alexandrovna Antsiferova ◽  
Marina Yurievna Kopaeva ◽  
Vyacheslav Nikolaevich Kochkin ◽  
Pavel Konstantinovich Kashkarov
Keyword(s):  
Silver Nanoparticles ◽  
Oral Administration ◽  
Dietary Supplement ◽  
Cognitive Functions ◽  
High Demand ◽  
Gastrointestinal Infections ◽  
Impaired Cognitive Function ◽  
Potential Risks ◽  
The Brain

Introduction. Since the beginning of the XXI century, silver nanoparticles have been widely used in various industries, medicine and pharmaceuticals due to their pronounced antibacterial, antiviral and fungicidal properties. In connection with such a high demand for the use of silver nanoparticles, it is very important to understand the associated potential risks from their use. Materials and methods. In the course of the work, there has been a study of the effects of the long-term oral administration of a commercially produced dietary supplement based on silver nanoparticles with a size of 34 nm and stabilized with polyvinylpyrrolidone in an amount of 50 μg/day/animal on the cognitive functions of C57Bl/6 mice, as well as their accumulation in the brain by the method of instrumental neutron activation analysis. The dietary supplement used is recommended for people as a treatment for gastrointestinal infections. Results. It was found that after 180 days of administration, silver nanoparticles impair long-term contextual memory, and over time, the content of silver in the brain increases. Conclusion. Presumably impaired cognitive function with accumulation of silver in the brains of mice. This poses the risk of prolonged oral use of the silver nanoparticles.

scholarly journals Disturbance in Mammalian Cognition Caused by Accumulation of Silver in Brain

Toxics ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 30 ◽  
Author(s):  
Anna A. Antsiferova ◽  
Marina Yu. Kopaeva ◽  
Vyacheslav N. Kochkin ◽  
Pavel K. Kashkarov ◽  
Mikhail V. Kovalchuk
Keyword(s):  
Silver Nanoparticles ◽  
Long Term Memory ◽  
Cell Integrity ◽  
Prolonged Administration ◽  
Term Memory ◽  
Histological Studies ◽  
Memory Impairments ◽  
Hippocampal Cell ◽  
The Brain

The influence of daily prolonged administration of silver nanoparticles on the cognitive functions of a model mammal was studied. The accumulation of silver in the whole brain and the hippocampus, cerebellum, cortex and residual brain tissue of the mouse was investigated by highly precise and representative neutron activation analysis, and histological studies were conducted. Here, we show that long-term memory impairments were caused by the accumulation of silver nanoparticles in the brain and its subregions, such as the hippocampus, cerebellum and cortex, in a step-like manner by disturbance of hippocampal cell integrity. Three different approaches allowed us to observe this phenomenon and discover the reasons it occurred.

scholarly journals Practical recommendations for the safe use of gadolinium in magnetic resonance imaging: a Delphi expert panel study

2020 ◽  
Vol 53 (4) ◽  
pp. 216-222
Author(s):  
Ronaldo Hueb Baroni ◽  
Tufik Bauab Jr. ◽  
Leonardo Kayat Bittencourt ◽  
Giuseppe D’Ippolito ◽  
Suzan Menasce Goldman ◽  
...  
Keyword(s):  
Adverse Reactions ◽  
Expert Panel ◽  
Panel Study ◽  
Delphi Panel ◽  
Gadolinium Deposition ◽  
Published Evidence ◽  
Potential Risks ◽  
The Brain ◽  
Practical Recommendations

Abstract Objective: To assess the practical aspects of the use of various gadolinium-based contrast agents (GBCAs) by radiologists. Materials and Methods: Ten experienced radiologists from different regions of Brazil participated in a Delphi panel querying their use of various GBCAs, including linear and macrocyclic classes (1.0 and 0.5 M), in terms of the choice of agent, volume and dosage of the agents, and associated safety concerns. Results: The response rate was 100% for all questions. GBCAs are safe in terms of acute adverse reactions, and nephrogenic systemic fibrosis is rare. The deposition of gadolinium in the brain and other tissues is a concern among the experts. Macrocyclic agents are preferable to linear agents; an injection volume below 0.1 mL/kg of a 1.0 M agent could result in good-quality images with additional long-term safety, but there is no published evidence to support this recommendation. The majority of experts preferred not to administer GBCAs to pregnant patients. Conclusion: When choosing a GBCA, it is important to consider the characteristics of the gadolinium deposition in patient tissues and minimize potential risks. Furthermore, medical education programs are needed to increase the awareness of the potential risks of gadolinium deposition and thus avoid instances of overexposure to the contrast agent.

scholarly journals Pseudomonas meningoencephalitis masquerading as a stroke in a patient on tocilizumab

2019 ◽  
Vol 12 (1) ◽  
pp. bcr-2018-227296 ◽  
Author(s):  
Cameron J Williams ◽  
Andrew Foote ◽  
Philip Choi
Keyword(s):  
High Dose ◽  
High Functioning ◽  
Vein Thrombosis ◽  
Potential Risks ◽  
Stroke Mimic ◽  
Deep Vein ◽  
The Brain ◽  
Limb Deep Vein Thrombosis

A previously high-functioning woman presents with clinical and CT features of a subacute ischaemic stroke. Her medical history is relevant for refractory giant cell arteritis on long-term high-dose prednisolone and recent commencement of tocilizumab (interleukin-6 monoclonal antibody). The potential for stroke mimic is considered and a magnetic resonance brain scan is requested. She rapidly deteriorates within 24 hours of admission and unexpectantly dies. An autopsy reveals that she has bilateral pulmonary emboli with lower limb deep vein thrombosis and Pseudomonas meningoencephalitis with frank pus on the brain. We discuss the potential risks of immunosuppression and the role of imaging in the diagnosis of stroke.

The Acute Effect of Alcohol on Various Memory Processes

2010 ◽  
Vol 24 (4) ◽  
pp. 249-252 ◽  
Author(s):  
Márk Molnár ◽  
Roland Boha ◽  
Balázs Czigler ◽  
Zsófia Anna Gaál
Keyword(s):  
Low Dose ◽  
Short Term Memory ◽  
Acute Effect ◽  
Long Term Memory ◽  
Term Memory ◽  
Memory Processes ◽  
Different Types ◽  
The Brain ◽  
Legal Consequences

This review surveys relevant and recent data of the pertinent literature regarding the acute effect of alcohol on various kinds of memory processes with special emphasis on working memory. The characteristics of different types of long-term memory (LTM) and short-term memory (STM) processes are summarized with an attempt to relate these to various structures in the brain. LTM is typically impaired by chronic alcohol intake but according to some data a single dose of ethanol may have long lasting effects if administered at a critically important age. The most commonly seen deleterious acute effect of alcohol to STM appears following large doses of ethanol in conditions of “binge drinking” causing the “blackout” phenomenon. However, with the application of various techniques and well-structured behavioral paradigms it is possible to detect, albeit occasionally, subtle changes of cognitive processes even as a result of a low dose of alcohol. These data may be important for the consideration of legal consequences of low-dose ethanol intake in conditions such as driving, etc.

Moving past the vaccine/autism controversy - to examine potential vaccine neurological harms

2020 ◽  
pp. 1-15
Author(s):  
Peter R. Breggin
Keyword(s):  
Neurological Disorders ◽  
Developmental Disorder ◽  
Physical Symptoms ◽  
Psychosocial Disorders ◽  
The Us ◽  
Potential Vaccine ◽  
Research And Education ◽  
The Brain ◽  
New Vaccines

BACKGROUND: The vaccine/autism controversy has caused vast scientific and public confusion, and it has set back research and education into genuine vaccine-induced neurological disorders. The great strawman of autism has been so emphasized by the vaccine industry that it, and it alone, often appears in authoritative discussions of adverse effects of the MMR and other vaccines. By dismissing the chimerical vaccine/autism controversy, vaccine defenders often dismiss all genuinely neurological aftereffects of the MMR (measles, mumps, and rubella) and other vaccines, including well-documented events, such as relatively rare cases of encephalopathy and encephalitis. OBJECTIVE: This report explains that autism is not a physical or neurological disorder. It is not caused by injury or disease of the brain. It is a developmental disorder that has no physical origins and no physical symptoms. It is extremely unlikely that vaccines are causing autism; but it is extremely likely that they are causing more neurological damage than currently appreciated, some of it resulting in psychosocial disabilities that can be confused with autism and other psychosocial disorders. This confusion between a developmental, psychosocial disorder and a physical neurological disease has played into the hands of interest groups who want to deny that vaccines have any neurological and associated neuropsychiatric effects. METHODS: A review of the scientific literature, textbooks, and related media commentary is integrated with basic clinical knowledge. RESULTS: This report shows how scientific sources have used the vaccine/autism controversy to avoid dealing with genuine neurological risks associated with vaccines and summarizes evidence that vaccines, including the MMR, can cause serious neurological disorders. Manufacturers have been allowed by the US Food and Drug Administration (FDA) to gain vaccine approval without placebo-controlled clinical trials. CONCLUSIONS: The misleading vaccine autism controversy must be set aside in favor of examining actual neurological harms associated with vaccines, including building on existing research that has been ignored. Manufacturers of vaccines must be required to conduct placebo-controlled clinical studies for existing vaccines and for government approval of new vaccines. Many probable or confirmed neurological adverse events occur within a few days or weeks after immunization and could be detected if the trials were sufficiently large. Contrary to current opinion, large, long-term placebo-controlled trials of existing and new vaccines would be relatively easy and safe to conduct.

Long-term management of patients with multiple brain metastases after shaped beam radiosurgery

2004 ◽  
pp. 406-412
Author(s):  
Paul Okunieff ◽  
Michael C. Schell ◽  
Russell Ruo ◽  
E. Ronald Hale ◽  
Walter G. O'Dell ◽  
...  
Keyword(s):  
Brain Metastases ◽  
Tumor Control ◽  
Content Type ◽  
Negative Results ◽  
Multiple Metastases ◽  
Extracranial Disease ◽  
Successful Control ◽  
The Brain

✓ The role of radiosurgery in the treatment of patients with advanced-stage metastatic disease is currently under debate. Previous randomized studies have not consistently supported the use of radiosurgery to treat patients with numbers of brain metastases. In negative-results studies, however, intracranial tumor control was high but extracranial disease progressed; thus, patient survival was not greatly affected, although neurocognitive function was generally maintained until death. Because the future promises improved systemic (extracranial) therapy, the successful control of brain disease is that much more crucial. Thus, for selected patients with multiple metastases to the brain who remain in good neurological condition, aggressive lesion-targeting radiosurgery should be very useful. Although a major limitation to success of this therapy is the lack of control of extracranial disease in most patients, it is clear that well-designed, aggressive treatment substantially decreases the progression of brain metastases and also improves neurocognitive survival. The authors present the management and a methodology for rational treatment of a patient with breast cancer who has harbored 24 brain metastases during a 3-year period.

Sign in / Sign up

Export Citation Format

Share Document