Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21.399
Filtrar
1.
Chiropr Man Therap ; 28(1): 34, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517803

RESUMO

BACKGROUND: Social media has become an increasingly important tool in monitoring the onset and spread of infectious diseases globally as well monitoring the spread of information about those diseases. This includes the spread of misinformation, which has been documented within the context of the emerging COVID-19 crisis. Understanding the creation, spread and uptake of social media misinformation is of critical importance to public safety. In this descriptive study, we detail Twitter activity regarding spinal manipulative therapy (SMT) and claims it increases, or "boosts", immunity. Spinal manipulation is a common intervention used by many health professions, most commonly by chiropractors. There is no clinical evidence that SMT improves human immunity. METHODS: Social media searching software (Talkwalker Quick Search) was used to describe Twitter activity regarding SMT and improving or boosting immunity. Searches were performed for the 3 months and 12 months before March 31, 2020 using terms related to 1) SMT, 2) the professions that most often provide SMT and 3) immunity. From these searches, we determined the magnitude and time course of Twitter activity then coded this activity into content that promoted or refuted a SMT/immunity link. Content themes, high-influence users and user demographics were then stratified as either promoting or refuting this linkage. RESULTS: Twitter misinformation regarding a SMT/immunity link increased dramatically during the onset of the COVID crisis. Activity levels (number of tweets) and engagement scores (likes + retweets) were roughly equal between content promoting or refuting a SMT/immunity link, however, the potential reach (audience) of tweets refuting a SMT/immunity link was 3 times higher than those promoting a link. Users with the greatest influence on Twitter, as either promoters or refuters, were individuals, not institutions or organizations. The majority of tweets promoting a SMT/immunity link were generated in the USA while the majority of refuting tweets originated from Canada. CONCLUSION: Twitter activity about SMT and immunity increased during the COVID-19 crisis. Results from this work have the potential to help policy makers and others understand the impact of SMT misinformation and devise strategies to mitigate its impact.


Assuntos
Betacoronavirus/imunologia , Comunicação , Infecções por Coronavirus/imunologia , Imunidade/fisiologia , Manipulação da Coluna , Pneumonia Viral/imunologia , Mídias Sociais/estatística & dados numéricos , Humanos , Pandemias , Mídias Sociais/normas , Fatores de Tempo
2.
Chiropr Man Therap ; 28: 34, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32523681

RESUMO

Background: Social media has become an increasingly important tool in monitoring the onset and spread of infectious diseases globally as well monitoring the spread of information about those diseases. This includes the spread of misinformation, which has been documented within the context of the emerging COVID-19 crisis. Understanding the creation, spread and uptake of social media misinformation is of critical importance to public safety. In this descriptive study, we detail Twitter activity regarding spinal manipulative therapy (SMT) and claims it increases, or "boosts", immunity. Spinal manipulation is a common intervention used by many health professions, most commonly by chiropractors. There is no clinical evidence that SMT improves human immunity. Methods: Social media searching software (Talkwalker Quick Search) was used to describe Twitter activity regarding SMT and improving or boosting immunity. Searches were performed for the 3 months and 12 months before March 31, 2020 using terms related to 1) SMT, 2) the professions that most often provide SMT and 3) immunity. From these searches, we determined the magnitude and time course of Twitter activity then coded this activity into content that promoted or refuted a SMT/immunity link. Content themes, high-influence users and user demographics were then stratified as either promoting or refuting this linkage. Results: Twitter misinformation regarding a SMT/immunity link increased dramatically during the onset of the COVID crisis. Activity levels (number of tweets) and engagement scores (likes + retweets) were roughly equal between content promoting or refuting a SMT/immunity link, however, the potential reach (audience) of tweets refuting a SMT/immunity link was 3 times higher than those promoting a link. Users with the greatest influence on Twitter, as either promoters or refuters, were individuals, not institutions or organizations. The majority of tweets promoting a SMT/immunity link were generated in the USA while the majority of refuting tweets originated from Canada. Conclusion: Twitter activity about SMT and immunity increased during the COVID-19 crisis. Results from this work have the potential to help policy makers and others understand the impact of SMT misinformation and devise strategies to mitigate its impact.


Assuntos
Comunicação , Infecções por Coronavirus , Imunidade , Imunização Secundária , Manipulação da Coluna/métodos , Pandemias , Pneumonia Viral , Mídias Sociais , Betacoronavirus/isolamento & purificação , Quiroprática/métodos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Humanos , Disseminação de Informação/ética , Disseminação de Informação/métodos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Saúde Pública/métodos , Mídias Sociais/ética , Mídias Sociais/estatística & dados numéricos , Resultado do Tratamento
3.
Rev Med Suisse ; 16(698): 1266-1269, 2020 Jun 17.
Artigo em Francês | MEDLINE | ID: mdl-32558457

RESUMO

The microbiota is a subject of particular interest and research. It is defined as all microorganisms present in tissues and on body surfaces. It sits at the interface with many systems, including the immune system, plays a role in the metabolism, immunity, or inflammation and is thought to be associated with some pathological mechanisms. Its composition and metabolic activity are influenced by diverse factors such as aging. This article summarizes the 5th symposium «â€…Feeding the Microbiota ¼ (Geneva University Hospitals, February 6, 2020), focused on microbiota and aging.


Assuntos
Envelhecimento/metabolismo , Microbiota/fisiologia , Idoso , Humanos , Imunidade , Inflamação/microbiologia
6.
Science ; 368(6491): 600-603, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381715

RESUMO

The blood and immune systems develop in parallel during early prenatal life. Waves of hematopoiesis separated in anatomical space and time give rise to circulating and tissue-resident immune cells. Previous observations have relied on animal models, which differ from humans in both their developmental timeline and exposure to microorganisms. Decoding the composition of the human immune system is now tractable using single-cell multi-omics approaches. Large-scale single-cell genomics, imaging technologies, and the Human Cell Atlas initiative have together enabled a systems-level mapping of the developing human immune system and its emergent properties. Although the precise roles of specific immune cells during development require further investigation, the system as a whole displays malleable and responsive properties according to developmental need and environmental challenge.


Assuntos
Sistema Imunitário/embriologia , Imunidade , Animais , Medula Óssea/embriologia , Medula Óssea/imunologia , Genômica/métodos , Hematopoese/imunologia , Humanos , Sistema Imunitário/microbiologia , Fígado/embriologia , Fígado/imunologia , Modelos Animais , Análise de Célula Única/métodos , Saco Vitelino
7.
Science ; 368(6491): 612-615, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381718

RESUMO

Neonates are particularly susceptible to infection. This vulnerability occurs despite their responsiveness to most vaccines. However, current vaccines do not target the pathogens responsible for most of the severe neonatal infections, and the time it takes to induce protective pathogen-specific immunity after vaccination limits protection in the first days to weeks of life. Alternative strategies include using vaccines to broadly stimulate neonatal immunity in a pathogen-agnostic fashion or vaccinating women during pregnancy to induce protective antibodies that are vertically transferred to offspring within their window of vulnerability. Protection may be further improved by integrating these approaches, namely vaccinating the neonate under the cover of vertically transferred maternal immunity. The rationale for and knowledge gaps related to each of these alternatives are discussed.


Assuntos
Imunidade Materno-Adquirida/imunologia , Imunidade , Vacinação/métodos , Vacinas/imunologia , Feminino , Humanos , Recém-Nascido , Gravidez
9.
Inflamm Res ; 69(7): 635-640, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32350571

RESUMO

At the population level, the virus-host relationship is not set up to end with the complete elimination of either or both. Pathogen-resistant individuals will always remain in the host population. In turn, the virus can never completely eliminate the host population, because evolutionarily such an event is a dead end for the virus as an obligate intracellular parasite. A certain existential balance exists in the virus-host relationship. Against this backdrop, viral epidemics and pandemics only become manifest and egregious to human beings when tens and hundreds of thousands of people die and the question emerges what caused the high mortality peaks on the death chart. The answer seems clear; the emerging strain of the virus is new to the host population, and new mutations of the virus and natural selection will lead to a survival of only genetically resistant individuals in a host population. The dangers inherent to a novel virus are due to new features generally inthe molecular structure of proteins, which enable the virus to infect the cells of the host organism more intensively, dramatically challenging host immunity, and thus be transmitted more readily in the host population. In this article, we will concentrate on the facts currently available about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has caused COVID-19 (coronavirus disease 2019) pandemic and try to predict its development and consequences based on the virus-host relationship. In fact, only two scenarios will occur simultaneously in the very near future: people who are genetically resistant to the virus will get sick, recover, and develop immunity, while people who are sensitive to the virus will need drugs and vaccines, which will have to be researched and developed if they are to recover. If the pandemic does not stop, in a few decades it is anticipated that SARS-CoV-2 will become as safe as the four non-severe acute respiratory syndrome human coronaviruses (HCoV-NL63, HCoV-HKU1, HCoV-OC43, and HCoV-229E) currently circulating but causing low mortality in the human population.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Interações Hospedeiro-Patógeno , Pneumonia Viral/virologia , Animais , Betacoronavirus/genética , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Resistência à Doença/genética , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Imunidade/genética , Imunidade/imunologia , Pandemias/prevenção & controle , Peptidil Dipeptidase A , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Seleção Genética/imunologia , Vacinas Virais , Replicação Viral
10.
Aging (Albany NY) ; 12(10): 9959-9981, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32470948

RESUMO

The severity and outcome of coronavirus disease 2019 (COVID-19) largely depends on a patient's age. Adults over 65 years of age represent 80% of hospitalizations and have a 23-fold greater risk of death than those under 65. In the clinic, COVID-19 patients most commonly present with fever, cough and dyspnea, and from there the disease can progress to acute respiratory distress syndrome, lung consolidation, cytokine release syndrome, endotheliitis, coagulopathy, multiple organ failure and death. Comorbidities such as cardiovascular disease, diabetes and obesity increase the chances of fatal disease, but they alone do not explain why age is an independent risk factor. Here, we present the molecular differences between young, middle-aged and older people that may explain why COVID-19 is a mild illness in some but life-threatening in others. We also discuss several biological age clocks that could be used in conjunction with genetic tests to identify both the mechanisms of the disease and individuals most at risk. Finally, based on these mechanisms, we discuss treatments that could increase the survival of older people, not simply by inhibiting the virus, but by restoring patients' ability to clear the infection and effectively regulate immune responses.


Assuntos
Envelhecimento/fisiologia , Infecções por Coronavirus , Epigênese Genética/fisiologia , Imunidade/fisiologia , Pandemias , Administração dos Cuidados ao Paciente/métodos , Pneumonia Viral , Idoso , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , Comorbidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/imunologia , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , Síndrome do Desconforto Respiratório do Adulto/etiologia , Síndrome do Desconforto Respiratório do Adulto/imunologia , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
11.
ACS Chem Neurosci ; 11(12): 1696-1698, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32452670

RESUMO

Although there is no reported genetic predisposition in contracting coronavirus disease 2019 (COVID-19), the mortality rate varies among different ethnic groups. Here we determined potential correlation between COVID-19 and spice consumption. The data from 163 countries including total cases, total deaths, and total recovered were analyzed. It was observed that there is a clear interrelated prevalence between the total number of COVID-19 cases per million population tested and the gram of spice supply per capita per day. Nations with lower consumptions of spices per capita showed greater number of COVID-19 cases per million population. This is not surprising as herbs and spices are well-known to boost immunity. Although the precise molecular mechanisms associated with spices and immunity are not completely understood, our findings led us to hypothesize that spice consumption plays a role in our ability to fight COVID-19; however, intensive research is needed to determine the translational value of these findings.


Assuntos
Infecções por Coronavirus/epidemiologia , Dieta/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Especiarias/estatística & dados numéricos , Betacoronavirus , Infecções por Coronavirus/imunologia , Suscetibilidade a Doenças/imunologia , Humanos , Imunidade/imunologia , Pandemias , Pneumonia Viral/imunologia , Prevalência
12.
Cell Host Microbe ; 27(5): 687-688, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32407704

RESUMO

In this issue of Cell Host & Microbe, Yeung et al. (2020) and Lin et al. (2020) expose laboratory mice to a natural environment and use immune and microbiota characterization to show that fungi promote more human-like immunity. These studies will help develop animal models to more accurately resemble human immune responses.


Assuntos
Fungos , Microbiota , Animais , Proteínas Relacionadas à Autofagia , Proteínas de Transporte , Humanos , Imunidade , Camundongos , Modelos Animais , Proteína Adaptadora de Sinalização NOD2
13.
Gene ; 747: 144682, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32304786

RESUMO

Human Papillomavirus 16 (HPV16) is the most oncogenic HPV and the most associated genotype with cervical cancer development and progression. Currently, all developed vaccines are targeting HPV16 and were designed based on the major L1 capsid protein. Thus, evaluation of the diversity of HPV16 L1 sequence, mainly in the antigenic regions, will be of a great interest to assess the efficacy of the prophylactic vaccines and to predict the impact of genetic variations in these regions on the vaccination-induced immunity. A total of 377 HPV16 L1 sequences, published in public domain GenBank database, from the Americas, Africa, Asia, and Europe were collected and assembled. A total of 626 mutation events affecting 83 distinct nucleotides into the five antigenic regions of L1 gene of HPV16 were reported, and most SNPs were located in DE (27.38%, 23/83) and FG (31%, 26/83) loops. Overall, 4 mutations were frequently found in HPV16 sequences: T176N and N181T in EF loop; A266T in the FG loop and T353P/I/N HI loop. Of particular interest, some SNPs are ubiquitous and were found in all populations whereas others were population specific and their presence was limited to one or 2 at the maximum. Association between mutations in the antigenic regions and ethnicity was also investigated and showed that mutations in BC and DE loops were present with no significant difference in sequences from Europe, Asia, America and Africa. However, most mutations in FG loop are reported in sequences from European cases and are less pronounced in cases from America and Asia, whereas mutations EF and HI loops prevail in Asian cases. These data highlight a high number of variant amino acid residues that could affect the vaccination-induced immunity and impact the effectiveness of the prophylactic vaccination to fight against HPV, warranting the need of further investigation for vaccines and natural history studies of HPV16.


Assuntos
Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Variação Genética , Papillomavirus Humano 16/genética , Imunidade , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/imunologia , Vacinação , Aminoácidos/genética , Antígenos Virais/imunologia , Sequência de Bases , Grupos Étnicos/genética , Humanos , Modelos Moleculares , Mutação/genética , Filogenia , Polimorfismo de Nucleotídeo Único/genética
14.
JCI Insight ; 5(10)2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32324595

RESUMO

BACKGROUNDThe coronavirus disease 2019 (COVID-19), infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a severe outbreak throughout the world. The host immunity of COVID-19 patients is unknown.METHODSThe routine laboratory tests and host immunity in COVID-19 patients with different severity of illness were compared after patient admission.RESULTSA total of 65 SARS-CoV-2-positive patients were classified as having mild (n = 30), severe (n = 20), and extremely severe (n = 15) illness. Many routine laboratory tests, such as ferritin, lactate dehydrogenase, and D-dimer, were increased in severe and extremely severe patients. The absolute numbers of CD4+ T cells, CD8+ T cells, and B cells were gradually decreased with increased severity of illness. The activation markers such as HLA-DR and CD45RO expressed on CD4+ and CD8+ T cells were increased in severe and extremely severe patients compared with mild patients. The costimulatory molecule CD28 had opposite results. The percentage of natural Tregs was decreased in extremely severe patients. The percentage of IFN-γ-producing CD8+ T cells was increased in both severe and extremely severe patients compared with mild patients. The percentage of IFN-γ-producing CD4+ T cells was increased in extremely severe patients. IL-2R, IL-6, and IL-10 were all increased in extremely severe patients. The activation of DC and B cells was decreased in extremely severe patients.CONCLUSIONThe number and function of T cells are inconsistent in COVID-19 patients. The hyperfunction of CD4+ and CD8+ T cells is associated with the pathogenesis of extremely severe SARS-CoV-2 infection.FUNDINGThis work was funded by the National Mega Project on Major Infectious Disease Prevention (2017ZX10103005-007) and the Fundamental Research Funds for the Central Universities (2019kfyRCPY098).


Assuntos
Infecções por Coronavirus/imunologia , Infecções por Coronavirus/fisiopatologia , Pneumonia Viral/imunologia , Pneumonia Viral/fisiopatologia , Betacoronavirus , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Citocinas/metabolismo , Testes Diagnósticos de Rotina , Feminino , Humanos , Imunidade , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Índice de Gravidade de Doença , Linfócitos T/imunologia
15.
Urologe A ; 59(5): 607-612, 2020 May.
Artigo em Alemão | MEDLINE | ID: mdl-32338303

RESUMO

On 1 March 2020, the amendments to the German Protection Against Infection Act that were introduced by the act to protect against measles and strengthen vaccination prevention (Measles Protection Act) entered into force. The reason for the changes is that the number of individuals with measles has significantly increased in recent years. To protect public health, the Measles Protection Act has implemented regulations requiring that persons in certain institutions must either have adequate protection against measles or have immunity to measles. In this article the current legal situation with regard to health care facilities is presented.


Assuntos
Política de Saúde , Controle de Infecções , Vacina contra Sarampo/administração & dosagem , Sarampo/prevenção & controle , Saúde Pública , Vacinação , Humanos , Imunidade , Controle de Infecções/legislação & jurisprudência , Rubéola (Sarampo Alemão)
16.
Clin Rheumatol ; 39(7): 2055-2062, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32277367

RESUMO

The ongoing pandemic coronavirus disease 19 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a matter of global concern. Environmental factors such as air pollution and smoking and comorbid conditions (hypertension, diabetes mellitus and underlying cardio-respiratory illness) likely increase the severity of COVID-19. Rheumatic manifestations such as arthralgias and arthritis may be prevalent in about a seventh of individuals. COVID-19 can result in acute interstitial pneumonia, myocarditis, leucopenia (with lymphopenia) and thrombocytopenia, also seen in rheumatic diseases like lupus and Sjogren's syndrome. Severe disease in a subset of patients may be driven by cytokine storm, possibly due to secondary hemophagocytic lymphohistiocytosis (HLH), akin to that in systemic onset juvenile idiopathic arthritis or adult-onset Still's disease. In the absence of high-quality evidence in this emerging disease, understanding of pathogenesis may help postulate potential therapies. Angiotensin converting enzyme 2 (ACE2) appears important for viral entry into pneumocytes; dysbalance in ACE2 as caused by ACE inhibitors or ibuprofen may predispose to severe disease. Preliminary evidence suggests potential benefit with chloroquine or hydroxychloroquine. Antiviral drugs like lopinavir/ritonavir, favipiravir and remdesivir are also being explored. Cytokine storm and secondary HLH might require heightened immunosuppressive regimens. Current international society recommendations suggest that patients with rheumatic diseases on immunosuppressive therapy should not stop glucocorticoids during COVID-19 infection, although minimum possible doses may be used. Disease-modifying drugs should be continued; cessation may be considered during infection episodes as per standard practices. Development of a vaccine may be the only effective long-term protection against this disease.Key Points• Patients with coronavirus disease 19 (COVID-19) may have features mimicking rheumatic diseases, such as arthralgias, acute interstitial pneumonia, myocarditis, leucopenia, lymphopenia, thrombocytopenia and cytokine storm with features akin to secondary hemophagocytic lymphohistiocytosis.• Although preliminary results may be encouraging, high-quality clinical trials are needed to better understand the role of drugs commonly used in rheumatology like hydroxychloroquine and tocilizumab in COVID-19.• Until further evidence emerges, it may be cautiously recommended to continue glucocorticoids and other disease-modifying antirheumatic drugs (DMARDs) in patients receiving these therapies, with discontinuation of DMARDs during infections as per standard practice.


Assuntos
Infecções por Coronavirus , Imunidade/efeitos dos fármacos , Conduta do Tratamento Medicamentoso , Pandemias , Pneumonia Viral , Doenças Reumáticas , Antirreumáticos/farmacologia , Betacoronavirus/isolamento & purificação , Comorbidade , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Humanos , Seleção de Pacientes , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/epidemiologia , Índice de Gravidade de Doença
17.
Science ; 368(6489)2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32327570

RESUMO

Protein quality control is essential for the proper function of cells and the organisms that they make up. The resulting loss of proteostasis, the processes by which the health of the cell's proteins is monitored and maintained at homeostasis, is associated with a wide range of age-related human diseases. Here, we highlight how the integrated stress response (ISR), a central signaling network that responds to proteostasis defects by tuning protein synthesis rates, impedes the formation of long-term memory. In addition, we address how dysregulated ISR signaling contributes to the pathogenesis of complex diseases, including cognitive disorders, neurodegeneration, cancer, diabetes, and metabolic disorders. The development of tools through which the ISR can be modulated promises to uncover new avenues to diminish pathologies resulting from it for clinical benefit.


Assuntos
Fator de Iniciação 2 em Eucariotos/metabolismo , Proteostase , Estresse Fisiológico , Fatores de Complexo Ternário/metabolismo , Acetamidas/química , Acetamidas/farmacologia , Animais , Cicloexilaminas/química , Cicloexilaminas/farmacologia , Fator de Iniciação 2 em Eucariotos/antagonistas & inibidores , Humanos , Imunidade , Doenças Metabólicas/metabolismo , Camundongos , Neoplasias/metabolismo , Fosfotransferases/metabolismo
18.
Exerc Immunol Rev ; 26: 8-22, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32139352

RESUMO

Multiple studies in humans and animals have demonstrated the profound impact that exercise can have on the immune system. There is a general consensus that regular bouts of short-lasting (i.e. up to 45 minutes) moderate intensity exercise is beneficial for host immune defense, particularly in older adults and people with chronic diseases. In contrast, infection burden is reported to be high among high performance athletes and second only to injury for the number of training days lost during preparation for major sporting events. This has shaped the common view that arduous exercise (i.e. those activities practiced by high performance athletes/ military personnel that greatly exceed recommended physical activity guidelines) can suppress immunity and increase infection risk. However, the idea that exercise per se can suppress immunity and increase infection risk independently of the many other factors (e.g. anxiety, sleep disruption, travel, exposure, nutritional deficits, environmental extremes, etc.) experienced by these populations has recently been challenged. The purpose of this debate article was to solicit opposing arguments centered around this fundamental question in the exercise immunology field: can exercise affect immune function to increase susceptibility to infection. Issues that were contested between the debating groups include: (i) whether or not athletes are more susceptible to infection (mainly of the upper respiratory tract) than the general population; (ii) whether exercise per se is capable of altering immunity to increase infection risk independently of the multiple factors that activate shared immune pathways and are unique to the study populations involved; (iii) the usefulness of certain biomarkers and the interpretation of in vitro and in vivo data to monitor immune health in those who perform arduous exercise; and (iv) the quality of scientific evidence that has been used to substantiate claims for and against the potential negative effects of arduous exercise on immunity and infection risk. A key point of agreement between the groups is that infection susceptibility has a multifactorial underpinning. An issue that remains to be resolved is whether exercise per se is a causative factor of increased infection risk in athletes. This article should provide impetus for more empirical research to unravel the complex questions that surround this contentious issue in the field of exercise immunology.


Assuntos
Suscetibilidade a Doenças/imunologia , Exercício Físico , Imunidade , Infecções/imunologia , Animais , Atletas , Humanos , Sistema Imunitário
20.
Nat Immunol ; 21(4): 369-380, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32205888

RESUMO

Lymph nodes (LNs) are strategically positioned at dedicated sites throughout the body to facilitate rapid and efficient immunity. Central to the structural integrity and framework of LNs, and the recruitment and positioning of leukocytes therein, are mesenchymal and endothelial lymph node stromal cells (LNSCs). Advances in the last decade have expanded our understanding and appreciation of LNSC heterogeneity, and the role they play in coordinating immunity has grown rapidly. In this review, we will highlight the functional contributions of distinct stromal cell populations during LN development in maintaining immune homeostasis and tolerance and in the activation and control of immune responses.


Assuntos
Sistema Imunitário/imunologia , Linfonodos/imunologia , Células Estromais/imunologia , Animais , Células Endoteliais/imunologia , Homeostase/imunologia , Humanos , Imunidade/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA