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1.
Cell Mol Neurobiol ; 43(6): 2621-2626, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36977809

RESUMO

Prion' is a term used to describe a protein infectious particle responsible for several neurodegenerative diseases in mammals, e.g., Creutzfeldt-Jakob disease. The novelty is that it is protein based infectious agent not involving a nucleic acid genome as found in viruses and bacteria. Prion disorders exhibit, in part, incubation periods, neuronal loss, and induce abnormal folding of specific normal cellular proteins due to enhancing reactive oxygen species associated with mitochondria energy metabolism. These agents may also induce memory, personality and movement abnormalities as well as depression, confusion and disorientation. Interestingly, some of these behavioral changes also occur in COVID-19 and mechanistically include mitochondrial damage caused by SARS-CoV-2 and subsequenct production of reactive oxygen species. Taken together, we surmise, in part, long COVID may involve the induction of spontaneous prion emergence, especially in individuals susceptible to its origin may thus explain some of its manesfestions post-acute viral infection.


Assuntos
COVID-19 , Príons , Humanos , Animais , Príons/metabolismo , Síndrome de COVID-19 Pós-Aguda , Espécies Reativas de Oxigênio , SARS-CoV-2 , Mamíferos/metabolismo
2.
Cell Mol Neurobiol ; 42(1): 99-107, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34117968

RESUMO

Mitochondrial DNA (mtDNA) heteroplasmy is the dynamically determined co-expression of wild type (WT) inherited polymorphisms and collective time-dependent somatic mutations within individual mtDNA genomes. The temporal expression and distribution of cell-specific and tissue-specific mtDNA heteroplasmy in healthy individuals may be functionally associated with intracellular mitochondrial signaling pathways and nuclear DNA gene expression. The maintenance of endogenously regulated tissue-specific copy numbers of heteroplasmic mtDNA may represent a sensitive biomarker of homeostasis of mitochondrial dynamics, metabolic integrity, and immune competence. Myeloid cells, monocytes, macrophages, and antigen-presenting dendritic cells undergo programmed changes in mitochondrial metabolism according to innate and adaptive immunological processes. In the central nervous system (CNS), the polarization of activated microglial cells is dependent on strategically programmed changes in mitochondrial function. Therefore, variations in heteroplasmic mtDNA copy numbers may have functional consequences in metabolically competent mitochondria in innate and adaptive immune processes involving the CNS. Recently, altered mitochondrial function has been demonstrated in the progression of coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Accordingly, our review is organized to present convergent lines of empirical evidence that potentially link expression of mtDNA heteroplasmy by functionally interactive CNS cell types to the extent and severity of acute and chronic post-COVID-19 neurological disorders.


Assuntos
COVID-19/genética , COVID-19/imunologia , DNA Mitocondrial/genética , Heteroplasmia/genética , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/imunologia , Animais , COVID-19/complicações , COVID-19/metabolismo , Humanos , Imunidade , Mitocôndrias/metabolismo , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/metabolismo
3.
Med Sci Monit ; 27: e931447, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33633106

RESUMO

Long-term sequelae of coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are now recognized. However, there is still a lack of consensus regarding the terminology for this emerging chronic clinical syndrome, which includes long COVID, chronic COVID syndrome, post-COVID-19 syndrome, post-acute COVID-19, and long-hauler COVID-19. In this review, I will use the term "long COVID". A review of the medical history and epidemiology of past pandemics and epidemics in modern literature review identifies common long-term post-infectious disorders, with the common finding of altered cognition. In the brain, the cerebral hypoxia induced by SARS-CoV-2 infection may be caused by mitochondrial dysfunction, resulting in "brain fog". Historically, the common symptom of altered cognition has been reported during earlier pandemics, which include the influenza pandemics of 1889 and 1892 (Russian flu), the Spanish flu pandemic (1918-1919), encephalitis lethargica, diphtheria, and myalgic encephalomyelitis (chronic fatigue syndrome or post-viral fatigue syndrome). There are similarities between chronic fatigue syndrome and the "brain fog" described in long COVID. During past viral epidemics and pandemics, a commonality of neural targets may have increased viral survival by conformational matching. The neurological and psychiatric sequelae of SARS-CoV-2 infection, or long COVID, may have emerged from neural effects that have emerged from an invertebrate and vertebrate virosphere. This review aims to present a historical overview of infections and disorders associated with neurological and psychiatric sequelae that have shown similarities with long COVID.


Assuntos
COVID-19/complicações , COVID-19/fisiopatologia , COVID-19/psicologia , Encéfalo/virologia , COVID-19/epidemiologia , COVID-19/metabolismo , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/virologia , História do Século XXI , Humanos , Influenza Pandêmica, 1918-1919 , Pandemias , SARS-CoV-2/enzimologia , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Síndrome de COVID-19 Pós-Aguda
4.
Med Sci Monit ; 27: e930886, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33487628

RESUMO

Alterations in brain functioning, especially in regions associated with cognition, can result from infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and are predicted to result in various psychiatric diseases. Recent studies have shown that SARS-CoV-2 infection and coronavirus disease 2019 (COVID-19) can directly or indirectly affect the central nervous system (CNS). Therefore, diseases associated with sequelae of COVID-19, or 'long COVID', also include serious long-term mental and cognitive changes, including the condition recently termed 'brain fog'. Hypoxia in the microenvironment of select brain areas may benefit the reproductive capacity of the virus. It is possible that in areas of cerebral hypoxia, neuronal cell energy metabolism may become compromised after integration of the viral genome, resulting in mitochondrial dysfunction. Because of their need for constant high metabolism, cerebral tissues require an immediate and constant supply of oxygen. In hypoxic conditions, neurons with the highest oxygen demand become dysfunctional. The resulting cognitive impairment benefits viral spread, as infected individuals exhibit behaviors that reduce protection against infection. The effects of compromised mitochondrial function may also be an evolutionary advantage for SARS-CoV-2 in terms of host interaction. A high viral load in patients with COVID-19 that involves the CNS results in the compromise of neurons with high-level energy metabolism. Therefore, we propose that selective neuronal mitochondrial targeting in SARS-CoV-2 infection affects cognitive processes to induce 'brain fog' and results in behavioral changes that favor viral propagation. Cognitive changes associated with COVID-19 will have increasing significance for patient diagnosis, prognosis, and long-term care.


Assuntos
COVID-19/metabolismo , Disfunção Cognitiva/metabolismo , Comportamentos Relacionados com a Saúde , Hipóxia Encefálica/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , SARS-CoV-2/fisiologia , COVID-19/complicações , COVID-19/fisiopatologia , COVID-19/psicologia , COVID-19/transmissão , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Metabolismo Energético , Humanos , Hipóxia Encefálica/fisiopatologia , Hipóxia Encefálica/psicologia , Viabilidade Microbiana , Carga Viral , Replicação Viral , Síndrome de COVID-19 Pós-Aguda
5.
Med Sci Monit ; 27: e931962, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33945520

RESUMO

Trait anxiety is characterized as a constant and often subliminal state that persists during daily life. Interoception is the perception of internal states and sensations, including from the autonomic nervous system. This review aims to develop a predictive model to explain the emergence, manifestations, and maintenance of trait anxiety. The model begins with the assumption that anxiety states arise from active interoceptive inference. The subsequent activation of autonomic responses results from aversive sensory encounters. A cognitive model is proposed for trait anxiety that includes the aversive sensory components from interoception, exteroception, and proprioception. A further component of the hypothesis is that repeated exposure to subliminal anxiety-evoking sensory elements can lead to an overgeneralization of this response to other inputs that are generally non-aversive. Increased uncertainty may result when predicting the sensory environment, resulting in arbitrary interoceptive anxiety responses that may be due to unjustifiable causes. Arbitrary successful or unsuccessful matching of predictions and responses reduces the individual's confidence to maintain the anxiety trait. In this review, the application of the proposed model is illustrated using gut microbial dysbiosis or imbalance of the gut microbiome.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Ansiedade/fisiopatologia , Cognição/fisiologia , Microbioma Gastrointestinal/fisiologia , Interocepção/fisiologia , Disbiose/fisiopatologia , Humanos
6.
Med Sci Monit ; 27: e933766, 2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34272353

RESUMO

Attention-Deficit/Hyperactivity Disorder (ADHD) is classically associated with symptoms that include inattentiveness, hyperactivity, and impulsivity together with a variety of other observable externalized symptoms. ADHD has also been associated with specific internalized cognitive symptoms, including restlessness and emotional impulsivity. This disorder has been recognized as a lifelong condition and can be recognized by a variety of unique cognitive phenomena. In addition to the frequently ignored affective symptoms exhibited by individuals diagnosed with ADHD, problems with time perception have been noted, although these are considered to be secondary issues. Temporal shifts in cognitive processing, however, may be at the very root of ADHD-related symptoms, given the importance of coordinated signal translation in the construction of behavior. In this review, we consider the evidence that suggests that differences in time perception are a central symptom in adults with ADHD. Some of these differences include the feeling of time moving faster, which causes difficulties in prospective time tasks and inaccuracies in time estimation tasks. We analyze the literature from both neurological and psychological perspectives and include an assessment of tools that can be administered via computer to measure time perception. We also suggest several computer-based methods that might be used to address problems with time perception in both children and adults. We strongly recommend the inclusion of ADHD symptoms associated with time perception in the next revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM) published by the American Psychiatric Association.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Percepção do Tempo , Adulto , Ansiedade , Atenção , Criança , Transtornos Cognitivos , Emoções , Humanos , Comportamento Impulsivo , Estudos Prospectivos , Inquéritos e Questionários
7.
Med Sci Monit ; 27: e933015, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34016942

RESUMO

Persistent comorbidities occur in patients who initially recover from acute coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). 'Long COVID' involves the central nervous system (CNS), resulting in neuropsychiatric symptoms and signs, including cognitive impairment or 'brain fog' and chronic fatigue syndrome. There are similarities in these persistent complications between SARS-CoV-2 and the Ebola, Zika, and influenza A viruses. Normal CNS neuronal mitochondrial function requires high oxygen levels for oxidative phosphorylation and ATP production. Recent studies have shown that the SARS-CoV-2 virus can hijack mitochondrial function. Persistent changes in cognitive functioning have also been reported with other viral infections. SARS-CoV-2 infection may result in long-term effects on immune processes within the CNS by causing microglial dysfunction. This short opinion aims to discuss the hypothesis that the pathogenesis of long-term neuropsychiatric COVID-19 involves microglia, mitochondria, and persistent neuroinflammation.


Assuntos
COVID-19/complicações , Sistema Nervoso Central/patologia , Disfunção Cognitiva/etiologia , Inflamação/patologia , Microglia/patologia , Mitocôndrias/patologia , COVID-19/patologia , Disfunção Cognitiva/patologia , Humanos , Neurônios/patologia , SARS-CoV-2
8.
Med Sci Monit ; 26: e928415, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32959807

RESUMO

The primordial origin of abiotic nitrogen fixation, which is not dependent on prokaryotes, reflects the importance of available nitrogenous compounds as an essential requirement for the emergence of life and evolutionary biodiversity. It has been hypothesized that synthesis of oxidized nitrogen in the form of nitrate (NO3-) and nitrite (NO2-), occurred in the prebiotic anoxic Hadean atmosphere. The sustained influx of atmospheric NO3- and NO2- into prebiotic Hadean oceans have been proposed to provide the essential substrates for abiotic synthesis of compounds such as ammonia (NH3) within oceanic alkaline hydrothermal vents in the seafloor. Because NH3 is an essential chemical precursor for nitrogen-containing molecular components of proteins and nucleic acids, abiotic production in high concentrations within Hadean oceanic alkaline hydrothermal vents is required for the emergence of diverse life forms. The chemical evolution of nitrogenous compounds includes the functional development of alkaloids. This commentary aims to critically discuss the possible origin of nitrogen-containing alkaloids and evolutionary processes in higher organisms, including the diverse biomedical mechanisms involved.


Assuntos
Alcaloides , Biodiversidade , Evolução Biológica , Fontes Hidrotermais , Oceanos e Mares
9.
Med Sci Monit ; 26: e929789, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33239605

RESUMO

Recent studies have shown a significant level of T cell immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in convalescent coronavirus disease 2019 (COVID-19) patients and unexposed healthy individuals. Also, SARS-CoV-2-reactive T memory cells occur in unexposed healthy individuals from endemic coronaviruses that cause the 'common cold.' The finding of the expression of adaptive SARS-CoV-2-reactive T memory cells in unexposed healthy individuals may be due to multiple cross-reactive viral protein targets following previous exposure to endemic human coronavirus infections. The opinion of the authors is that determination of protein sequence homologies across seemingly disparate viral protein libraries may provide epitope-matching data that link SARS-CoV-2-reactive T memory cell signatures to prior administration of cross-reacting vaccines to common viral pathogens. Exposure to SARS-CoV-2 initiates diverse cellular immune responses, including the associated 'cytokine storm'. Therefore, it is possible that the intact virus possesses a required degree of conformational matching, or stereoselectivity, to effectively target its receptor on multiple cell types. Therefore, conformational matching may be viewed as an evolving mechanism of viral infection and viral replication by an evolutionary modification of the angiotensin-converting enzyme 2 (ACE2) receptor required for SARS-CoV-2 binding and host cell entry. The authors propose that convalescent memory T cell immunity in individuals with mild or asymptomatic SARS-CoV-2 infection may result from an evolutionarily adapted immune response to coronavirus and the 'common cold'.


Assuntos
Enzima de Conversão de Angiotensina 2/genética , Infecções Assintomáticas , COVID-19/imunologia , Resfriado Comum/imunologia , Memória Imunológica/genética , Anticorpos Antivirais , COVID-19/sangue , COVID-19/diagnóstico , COVID-19/virologia , Resfriado Comum/prevenção & controle , Resfriado Comum/virologia , Reações Cruzadas/genética , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Evolução Molecular , Humanos , Imunidade Celular/genética , Imunogenicidade da Vacina , Rhinovirus/genética , Rhinovirus/imunologia , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Homologia de Sequência , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Internalização do Vírus , Replicação Viral/genética , Replicação Viral/imunologia
10.
Med Sci Monit ; 26: e928996, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33177481

RESUMO

Since the initial reports of coronavirus disease 2019 (COVID-19) in China in late 2019, infections from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have spread rapidly, resulting in a global pandemic that has caused millions of deaths. Initially, the large number of infected people required the direction of global healthcare resources to provide supportive care for the acutely ill population in an attempt to reduce mortality. While clinical trials for safe and effective antiviral agents are ongoing, and vaccine development programs are being accelerated, long-term sequelae of SARS-CoV-2 infection have become increasingly recognized and concerning. Although the upper and lower respiratory tracts are the main sites of entry of SARS-CoV-2 into the body, resulting in COVID-19 pneumonia as the most common presentation, acute lung damage may be followed by pulmonary fibrosis and chronic impairment of lung function, with impaired quality of life. Also, increasing reports have shown that SARS-CoV-2 infection involves the central nervous system (CNS) and the peripheral nervous system (PNS) and directly or indirectly damages neurons, leading to long-term neurological sequelae. This review aims to provide an update on the mechanisms involved in the development of the long-term sequelae of SARS-CoV-2 infection in the 3 main areas of lung injury, neuronal injury, and neurodegenerative diseases, including Alzheimer disease, Parkinson disease, and multiple sclerosis, and highlights the need for patient monitoring following the acute stage of infection with SARS-CoV-2 to provide a rationale for the prevention, diagnosis, and management of these potential long-term sequelae.


Assuntos
COVID-19/complicações , Lesão Pulmonar/epidemiologia , Doenças Neurodegenerativas/epidemiologia , Fibrose Pulmonar/epidemiologia , SARS-CoV-2/patogenicidade , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/virologia , Progressão da Doença , Humanos , Lesão Pulmonar/diagnóstico , Lesão Pulmonar/imunologia , Lesão Pulmonar/prevenção & controle , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/imunologia , Doenças Neurodegenerativas/prevenção & controle , Pandemias , Fibrose Pulmonar/diagnóstico , Fibrose Pulmonar/imunologia , Fibrose Pulmonar/prevenção & controle , Qualidade de Vida , SARS-CoV-2/imunologia , Fatores de Tempo
11.
Med Sci Monit ; 26: e930340, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33323916

RESUMO

Alterations in complex behavioral patterns during the extended period of the COVID-19 pandemic are predicted to promote a variety of psychiatric disease symptoms due to enforced social isolation and self-quarantine. Accordingly, multifaceted mental health problems will continue to increase, thereby creating a challenge for society and the health care system in general. Recent studies show that COVID-19 can directly or indirectly influence the central nervous system, potentially causing neurological pathologies such as Alzheimer disease and Parkinson disease. Thus, chronic COVID-19-related disease processes have the potential to cause serious mental illnesses, including depression, anxiety, and sleep disorders. Importantly, mental health problems can foster systemic changes in functionally-linked neuroendocrine conditions that heighten a person's susceptibility to COVID-19 infection. These altered defense mechanisms may include compromised "self-control" and "self-care", as well as a "lack of insight" into the danger posed by the virus. These consequences may have serious social impacts on the future of COVID-19 survivors. Compounding the functionally related issues of altered mental health parameters and viral susceptibility are the potential effects of compromised immunity on the establishment of functional herd immunity. Within this context, mental health takes on added importance, particularly in terms of the need to increase support for mental health research and community-based initiatives. Thus, COVID-19 infections continue to reveal mental health targets, a process we must now be prepared to deal with.


Assuntos
COVID-19/complicações , Saúde Mental , SARS-CoV-2/patogenicidade , Sobreviventes/psicologia , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/virologia , Ansiedade/epidemiologia , Ansiedade/prevenção & controle , Ansiedade/psicologia , COVID-19/epidemiologia , COVID-19/psicologia , Depressão/epidemiologia , Depressão/prevenção & controle , Depressão/psicologia , Suscetibilidade a Doenças/psicologia , Humanos , Pandemias , Doença de Parkinson/epidemiologia , Doença de Parkinson/prevenção & controle , Doença de Parkinson/virologia , Distanciamento Físico , Autocuidado/psicologia , Autocontrole/psicologia , Isolamento Social/psicologia
12.
Med Sci Monit ; 26: e924700, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32366816

RESUMO

The first outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurred in Wuhan, Hubei Province, China, in late 2019. The subsequent COVID-19 pandemic rapidly affected the health and economy of the world. The global approach to the pandemic was to isolate populations to reduce the spread of this deadly virus while vaccines began to be developed. In March 2020, the first phase I clinical trial of a novel lipid nanoparticle (LNP)-encapsulated mRNA-based vaccine, mRNA-1273, which encodes the spike protein (S protein) of SARS-CoV-2, began in the United States (US). The production of mRNA-based vaccines is a promising recent development in the production of vaccines. However, there remain significant challenges in the development and testing of vaccines as rapidly as possible to control COVID-19, which requires international collaboration. This review aims to describe the background to the rationale for the development of mRNA-based SARS-CoV-2 vaccines and the current status of the mRNA-1273 vaccine.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais , Vacina de mRNA-1273 contra 2019-nCoV , Betacoronavirus/imunologia , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/imunologia , Humanos , Pneumonia Viral/imunologia , RNA Mensageiro/imunologia , RNA Viral/imunologia , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Estados Unidos
13.
Med Sci Monit ; 26: e924337, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32225126

RESUMO

Over the past two decades, a major goal of our research group has been elucidation of the functional roles of several key regulatory molecules in proinflammatory preconditioning involved in the pathophysiology of seemingly diverse human disease states. By necessity, operational definitions of proinflammation must be intrinsically fluid based on recent advances in our understanding of complex regulation of innate and adaptive immune processes. Similar to systemic acute stress, a physiological proinflammatory state appears to be a key autoregulatory mechanism for maintaining optimal immune surveillance against potentially infective microorganisms, viruses, and toxic xenobiotics. Perturbation of normative biochemical and molecular mosaics of ongoing proinflammatory tone, exemplified by altered expression of pro- and anti-inflammatory cytokines and their respective protein complexes, is hypothesized to be a common modality for initiation and full expression of various autoimmune diseases and comorbid syndromes evolving from metabolic and metastatic diseases. The newly reported presence of "free" (extracellular) mitochondria exponentially adds to our hypothesis that in conditions of acute stress, a new source of potential ATP producers may be recruited and present to deal with such an acute process. Furthermore, given this phenomenon, an early surveillance role and a dysfunctional chronic inflammation-prolonging component may also be surmised.


Assuntos
Doenças Autoimunes/imunologia , Espaço Extracelular/imunologia , Inflamação/imunologia , Mitocôndrias/imunologia , Alarminas/imunologia , Alarminas/metabolismo , Animais , Anti-Inflamatórios/metabolismo , Doenças Autoimunes/sangue , Espaço Extracelular/metabolismo , Humanos , Inflamação/sangue , Mediadores da Inflamação/metabolismo , Mitocôndrias/metabolismo , Mitofagia/imunologia
14.
Med Sci Monit ; 26: e925679, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32454510

RESUMO

Nitric oxide (NO) represents a key signaling molecule in multiple regulatory pathways underlying vascular, metabolic, immune, and neurological function across animal phyla. Our brief critical discussion is focused on the multiple roles of the NO signaling pathways in the maintenance of basal physiological states of readiness in diverse cell types mediating innate immunological functions and in the facilitation of proinflammatory-mediated adaptive immunological responses associated with viral infections. Prior studies have reinforced the critical importance of constitutive NO signaling pathways in the homeostatic maintenance of the vascular endothelium, and state-dependent changes in innate immunological responses have been associated with a functional override of NO-mediated inhibitory tone. Accordingly, convergent lines of evidence suggest that dysregulation of NO signaling pathways, as well as canonical oxidative effects of inducible NO, may provide a permissive cellular environment for viral entry and replication. In immunologically compromised individuals, functional override and chronic rundown of inhibitory NO signaling systems promote aberrant expression of unregulated proinflammatory pathways resulting in widespread metabolic insufficiencies and structural damage to autonomous cellular and organ structures. We contend that restoration of normative NO tone via combined pharmaceutical, dietary, or complex behavioral interventions may partially reverse deleterious physiological conditions brought about by viral infection linked to unregulated adaptive immune responses.


Assuntos
Antivirais/farmacologia , Óxido Nítrico/farmacologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Animais , Humanos , Inflamação/metabolismo , Inflamação/patologia , Oxirredução , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , Transdução de Sinais
15.
Med Sci Monit ; 26: e926016, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32463026

RESUMO

The emergence of the novel ß-coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a global pandemic of coronavirus disease 2019 (COVID-19). Clinical studies have documented that potentially severe neurological symptoms are associated with SARS-CoV-2 infection, thereby suggesting direct CNS penetration by the virus. Prior studies have demonstrated that the destructive neurological effects of rabies virus (RABV) infections are mediated by CNS transport of the virus tightly bound to the nicotinic acetylcholine receptor (nAChR). By comparison, it has been hypothesized that a similar mechanism exists to explain the multiple neurological effects of SARS-CoV-2 via binding to peripheral nAChRs followed by orthograde or retrograde transport into the CNS. Genetic engineering of the RABV has been employed to generate novel vaccines consisting of non-replicating RABV particles expressing chimeric capsid proteins containing human immunodeficiency virus 1 (HIV-1), Middle East respiratory syndrome (MERS-CoV), Ebolavirus, and hepatitis C virus (HCV) sequences. Accordingly, we present a critical discussion that integrates lessons learned from prior RABV research and vaccine development into a working model of a SARS-CoV-2 vaccine that selectively targets and neutralizes CNS penetration of a tightly bound viral nAChR complex.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Vírus da Raiva/fisiologia , Receptores Nicotínicos/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Replicação Viral , Betacoronavirus/química , COVID-19 , Vacinas contra COVID-19 , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Humanos , Pandemias , Pneumonia Viral/virologia , Domínios Proteicos , Vírus da Raiva/genética , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Virais/química , Vacinas Virais/metabolismo
16.
Med Sci Monit ; 26: e927739, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32975239

RESUMO

Current critical thinking has displaced the elaborated beta amyloid theory as the underlying unitary mechanism of Alzheimer disease (AD) in favor of concerted, long-term disruption or dysregulation of broad-based physiological processes. We present a critical discussion in which a chronic state of systemic proinflammation sustained over the course of several decades and engendered by ongoing metabolic or autoimmune disease is predicted to promote severe disruptions of central neurological processes. Specifically, long-term functional rundown of microglial-mediated phagocytic activity in concert with aberrant expression and cellular deposition of beta amyloid and tau protein facilitates formation of senile plaques and neurofibrillary tangles. Within this functional context, we hypothesize that early initiation events in the pathophysiology of AD may operationally involve a convergence of dysregulated peripheral and central constitutive nitric oxide signaling pathways resulting from a chronic state of systemic proinflammation and leading to severely dysfunctional "hyperactivated" microglia.


Assuntos
Doença de Alzheimer , Microglia , Óxido Nítrico/metabolismo , Transdução de Sinais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Humanos , Microglia/metabolismo , Microglia/patologia
17.
Med Sci Monit ; 25: 9306-9309, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31809494

RESUMO

The relaxation response derives its health benefits by reestablishing "normal" equilibria between the sympathetic and parasympathetic branches of the autonomic nervous system. Recent work suggests that this behavioral training provides positive effects on mitochondrial bioenergetics, insulin secretion, and reductions in pro-inflammatory and stress-related pathways. We have previously contended, however, that correlative associations of relaxation training with positive changes in gene expression in selected biological systems are strongly suggestive of adaptive physiological changes, but do not elucidate an underlying, clinically compelling, unified mechanism of action consistent with its purported positive health effects. We surmise that any plausible model of behaviorally-mediated regulatory effects on whole-body metabolic processes must be intrinsically broad-based and multifaceted via integration of differential contributions of functionally interactive peripheral and CNS organ systems. Accordingly, the initiation of multiple cellular protective/anti-bio-senescence processes may have emerged during evolutionary development to ensure the survival of hybrid prokaryotic/eukaryotic progenitor cells, given the evolvement of oxidative metabolism and its associated negative byproducts. As an essential corollary, preservation and adaptation of multifaceted regulatory molecules, notably nitric oxide, paralleled the development of eukaryotic cell types via multifaceted stereo-selective recognition and conformational matching by complex biochemical and molecular enzyme systems. Hence, the relaxation response may be a manifestation of a metabolic corrective process/response, that may now include cognition ("awareness").


Assuntos
Respiração Celular/fisiologia , Mitocôndrias/metabolismo , Relaxamento/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Metabolismo Energético , Humanos , Mitocôndrias/fisiologia , Modelos Teóricos , Óxido Nítrico/metabolismo , Consumo de Oxigênio/fisiologia
18.
Med Sci Monit ; 25: 1102-1104, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30739121

RESUMO

Widespread usage of the calcineurin inhibitors tacrolimus and cyclosporine A as post-transplantation immunosuppressive agents is fraught with severe nephrotoxic and diabetogenic side effects. More recently, tapering of calcineurin inhibitor-based immunotherapies with concurrent administration of the mammalian target of rapamycin (mTOR) inhibitors sirolimus and everolimus has been employed within pharmacological regimens designed to achieve better safety and efficacy for preservation of allograft kidney function. Collected preclinical data and recent clinical study, however, indicate that usage of calcineurin inhibitors and/or mTOR blockers as immunosuppressive agents promotes equivalent diabetogenic side effects. Based on a wealth of validating preclinical studies, we contend that the favorable metabolic effects of mineralocorticoid receptor antagonists, such as spironolactone, support their inclusion in novel immunosuppressive strategies to inhibit new onset type II diabetic symptoms in post-transplantation patient populations.


Assuntos
Antagonistas de Receptores de Mineralocorticoides/farmacologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Espironolactona/uso terapêutico , Calcineurina/metabolismo , Inibidores de Calcineurina , Ciclosporina , Complicações do Diabetes/tratamento farmacológico , Diabetes Mellitus/induzido quimicamente , Everolimo , Rejeição de Enxerto/tratamento farmacológico , Humanos , Imunossupressores/metabolismo , Imunossupressores/farmacologia , Transplante de Rim , Sirolimo , Espironolactona/farmacologia , Tacrolimo , Tolerância ao Transplante/fisiologia
19.
Med Sci Monit ; 25: 6624-6630, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31481648

RESUMO

BACKGROUND Following renal transplantation, early-onset pneumonia is a frequent and severe infection-related complication. Red blood cell distribution width (RDW) has been reported as a predictive marker among patients with infectious diseases. Therefore, the aim of this study was to explore the significance of RDW in predicting prognosis, including 60-day mortality, in renal transplant recipients with early-onset pneumonia. MATERIAL AND METHODS Clinical data from patients who developed early-onset pneumonia after renal transplantation were retrospectively reviewed. Patients were divided into 2 groups: those with an RDW ≤15.0% and those with an RDW >15.0%. The 60-day mortality, bacteremia, need for mechanical ventilation, renal transplant rejection rate, and number of admissions to the intensive care unit (ICU) were estimated by Kaplan-Meier methods. Univariate and multivariate Cox regression analyses were performed to determine the risk factors for 60-day mortality. RESULTS Among the 118 patients participating in the study, 18 (15.2%) died during the 60-day follow-up. Kaplan-Meier analysis showed a death rate of 9.38% in the group with an RDW ≤15.0%, and a death rate of 40.9% in the group with an RDW >15.0% (P<0.001). Patient prognosis, including episodes of mechanical ventilation, graft rejection, and ICU admissions were significantly different between groups (P<0.01). RDW was an independent factor related to higher 60-day mortality (HR, 1.672; 95% CI, 1.111-2.516). CONCLUSIONS Among patients with early-onset pneumonia following renal transplantation, increased RDW >15.0% was significantly associated with prognosis and 60-day mortality.


Assuntos
Índices de Eritrócitos , Transplante de Rim , Pneumonia/sangue , Transplantados , Adulto , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais
20.
Med Sci Monit ; 25: 4974-4981, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31274132

RESUMO

BACKGROUND Burnout is a state of vital exhaustion that is manifested on physical, cognitive, and emotional levels. Teachers work in a field where they are exposed daily to high job-related stressors, which can result in job change, a higher rate of unhappiness, and even earlier retirement. This study explored the relationship between job stressors, lifestyle, and burnout. MATERIAL AND METHODS Descriptive statistics were used to explore the burnout levels, together with t tests to compare between men and women, and regression analysis was performed to explore the relationship between the rates of burnout and lifestyle. RESULTS The overall sample size was 2394 teachers from primary schools. While males had higher emotional burnout, females reported higher physical burnout rates. We found that higher income was associated with less burnout, and a healthier lifestyle is associated with lower burnout rates. Teachers who take time for family and personal interests have significantly lower rates of burnout than those that do not. CONCLUSIONS Based on our results, we propose that teachers should be informed about the risk of burnout. We found that some teachers reported they do not know what burnout syndrome is. The primary aim should be to increase awareness. In fact, burnout is a major threat to those who are perfectionists and who tend to work overtime.


Assuntos
Esgotamento Psicológico/psicologia , Estilo de Vida , Professores Escolares/psicologia , Adolescente , Adulto , Idoso , República Tcheca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Síndrome , Adulto Jovem
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