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1.
Infection ; 52(4): 1449-1458, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38499828

RESUMO

PURPOSE: In contrast to adults, immune protection against SARS-CoV-2 in children and adolescents with natural or hybrid immunity is still poorly understood. The aim of this study was to analyze different immune compartments in different age groups and whether humoral immune reactions correlate with a cellular immune response. METHODS: 72 children and adolescents with a preceding SARS-CoV-2 infection were recruited. 37 were vaccinated with an RNA vaccine (BNT162b2). Humoral immunity was analyzed 3-26 months (median 10 months) after infection by measuring Spike protein (S), nucleocapsid (NCP), and neutralizing antibodies (nAB). Cellular immunity was analyzed using a SARS-CoV-2-specific interferon-γ release assay (IGRA). RESULTS: All children and adolescents had S antibodies; titers were higher in those with hybrid immunity (14,900 BAU/ml vs. 2118 BAU/ml). NCP antibodies were detectable in > 90%. Neutralizing antibodies (nAB) were more frequently detected (90%) with higher titers (1914 RLU) in adolescents with hybrid immunity than in children with natural immunity (62.5%, 476 RLU). Children with natural immunity were less likely to have reactive IGRAs (43.8%) than adolescents with hybrid immunity (85%). The amount of interferon-γ released by T cells was comparable in natural and hybrid immunity. CONCLUSION: Spike antibodies are the most reliable markers to monitor an immune reaction against SARS-CoV-2. High antibody titers of spike antibodies and nAB correlated with cellular immunity, a phenomenon found only in adolescents with hybrid immunity. Hybrid immunity is associated with markedly higher antibody titers and a higher probability of a cellular immune response than a natural immunity.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Imunidade Celular , Imunidade Humoral , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , COVID-19/imunologia , Adolescente , Criança , Masculino , Feminino , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Pré-Escolar , Vacinas contra COVID-19/imunologia , Imunidade Inata , Proteínas do Nucleocapsídeo de Coronavírus/imunologia
2.
Laryngorhinootologie ; 102(2): 89-99, 2023 02.
Artigo em Alemão | MEDLINE | ID: mdl-36750110

RESUMO

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the mucous membranes of the nose and sinuses. Eosinophilic inflammation is described as a common endotype. The anti-IL5 antibody mepolizumab was approved in November 2021 as an add-on therapy to intranasal glucocorticosteroids for the treatment of adults with severe chronic rhinosinusitis with nasal polyps when systemic glucocorticosteroids or surgery do not provide adequate disease control. While national and international recommendations exist for the use of mepolizumab in CRSwNP, it has not yet been adequately specified how this therapy is to be monitored, what follow-up documentation is necessary, and when it should be terminated if necessary. METHODS: A literature search was performed to analyze previous data on the treatment of CRSwNP with mepolizumab and to determine the available evidence by searching Medline, Pubmed, the national and international trial and guideline registries and the Cochrane Library. Human studies published in the period up to and including 10/2022 were considered. RESULTS: Based on the international literature and previous experience by an expert panel, recommendations for follow-up, adherence to therapy intervals and possible therapy breaks, as well as termination of therapy when using mepolizumab for the indication CRSwNP in the German health care system are given on the basis of a documentation sheet. CONCLUSIONS: Understanding the immunological basis of CRSwNP opens up new non-surgical therapeutic approaches with biologics for patients with severe, uncontrolled courses. Here, we provide recommendations for follow-up, adherence to therapy intervals, possible therapy pauses, or discontinuation of therapy when mepolizumab is used as add-on therapy with intranasal glucocorticosteroids to treat adult patients with severe CRSwNP that cannot be adequately controlled with systemic glucocorticosteroids and/or surgical intervention.


Assuntos
Medicina Ambiental , Pólipos Nasais , Procedimentos Cirúrgicos Nasais , Rinite , Sinusite , Adulto , Humanos , Rinite/tratamento farmacológico , Doença Crônica , Sinusite/tratamento farmacológico , Atenção à Saúde
3.
Schmerz ; 36(6): 422-428, 2022 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-34762202

RESUMO

BACKGROUND: Cystic fibrosis (CF) is a rare genetic multisystemic disorder with progressive abdominal and pulmonary involvement. Pain is still an underestimated symptom in CF patients. METHODS: A comprehensive review of guidelines and scientific literature on the topic was performed and combined with findings from pain management in a young CF patient with progressive thoracic pain. RESULTS: German CF guidelines do not cover diagnosis and management of pain in these patients. Studies from Europe and the United States report interactions between intensity of pain and mortality in CF, but do not include data on the efficacy of pain management. These data and clinical observations of a CF patient with episodes of intense thoracic pain are used to illustrate the specific challenges in pain relief. CONCLUSION: Pain management in CF requires meticulous monitoring as well as an interdisciplinary approach and should be implemented in the German CF guidelines. The authors also want to suggest recommendations for the treatment of thoracic pain in CF. The range and severity of organ involvement complicates the use both of opioids and non-opioids. Especially opioid treatment carries the risk of hypoxia and opioid-induced constipation (OIC) and needs close medical supervision.


Assuntos
Fibrose Cística , Humanos , Estados Unidos , Fibrose Cística/complicações , Fibrose Cística/diagnóstico , Fibrose Cística/terapia , Manejo da Dor , Analgésicos Opioides/efeitos adversos , Constipação Intestinal , Dor/tratamento farmacológico
4.
Laryngorhinootologie ; 101(11): 855-865, 2022 11.
Artigo em Alemão | MEDLINE | ID: mdl-36150698

RESUMO

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a multifactorial inflammatory disease of the nasal and paranasal mucosa. A Type-2 inflammation is described as the most common endotype. Since October 2019 the anti-IL-4/-IL-13 antibody dupilumab has been approved in Germany as an add-on therapy to intranasal corticosteroids for the treatment of adults with severe chronic rhinosinusitis with nasal polyps, when systemic corticosteroids alone or surgery do not provide adequate disease control. While recommendations for the use of dupilumab in CRSwNP exist at both national and international levels, until now it has not been adequately established, how therapy should be monitored and when it should be discontinued in the German Health Care System. METHODS: A literature search was performed analyzing previous data on the treatment of CRSwNP with dupilumab and to determine the available evidence by searching Medline, Pubmed, the national and international trial and guideline registries and the Cochrane Library. Human studies published in the period up to 05/2022 were included. RESULTS: Based on international literature and previous experience, recommendations are given by an expert panel for follow-up and possible therapy breaks, therapy intervals or termination of therapy when using dupilumab for the indication CRSwNP in the German health care system based on a documentation form. CONCLUSIONS: Understanding the immunological basis of CRSwNP opens new non-surgical therapy approaches with biologics for patients with severe courses. The authors give recommendations for follow-up, possible therapy breaks, therapy intervals and a termination for dupilumab treatment as add-on therapy with intranasal corticosteroids for the treatment of adult patients with severe CRSwNP that cannot be adequately controlled with systemic corticosteroids and/or surgical intervention.


Assuntos
Pólipos Nasais , Rinite , Sinusite , Adulto , Humanos , Pólipos Nasais/tratamento farmacológico , Rinite/tratamento farmacológico , Sinusite/tratamento farmacológico , Doença Crônica , Corticosteroides/uso terapêutico , Atenção à Saúde , Documentação
5.
Phys Rev Lett ; 126(13): 137201, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33861132

RESUMO

We present an experimental study of time refraction of spin waves (SWs) propagating in microscopic waveguides under the influence of time-varying magnetic fields. Using space- and time-resolved Brillouin light scattering microscopy, we demonstrate that the broken translational symmetry along the time coordinate results in a loss of energy conservation for SWs and thus allows for a broadband and controllable shift of the SW frequency. With an integrated design of SW waveguide and microscopic current line for the generation of strong, nanosecond-long, magnetic field pulses, a conversion efficiency up to 39% of the carrier SW frequency is achieved, significantly larger compared to photonic systems. Given the strength of the magnetic field pulses and its strong impact on the SW dispersion relation, the effect of time refraction can be quantified on a length scale comparable to the SW wavelength. Furthermore, we utilize time refraction to excite SW bursts with pulse durations in the nanosecond range and a frequency shift depending on the pulse polarity.

6.
BMC Biol ; 18(1): 161, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33158442

RESUMO

BACKGROUND: The Wolbachia incompatible insect technique (IIT) shows promise as a method for eliminating populations of invasive mosquitoes such as Aedes aegypti (Linnaeus) (Diptera: Culicidae) and reducing the incidence of vector-borne diseases such as dengue, chikungunya and Zika. Successful implementation of this biological control strategy relies on high-fidelity separation of male from female insects in mass production systems for inundative release into landscapes. Processes for sex-separating mosquitoes are typically error-prone and laborious, and IIT programmes run the risk of releasing Wolbachia-infected females and replacing wild mosquito populations. RESULTS: We introduce a simple Markov population process model for studying mosquito populations subjected to a Wolbachia-IIT programme which exhibit an unstable equilibrium threshold. The model is used to study, in silico, scenarios that are likely to yield a successful elimination result. Our results suggest that elimination is best achieved by releasing males at rates that adapt to the ever-decreasing wild population, thus reducing the risk of releasing Wolbachia-infected females while reducing costs. CONCLUSIONS: While very high-fidelity sex separation is required to avoid establishment, release programmes tend to be robust to the release of a small number of Wolbachia-infected females. These findings will inform and enhance the next generation of Wolbachia-IIT population control strategies that are already showing great promise in field trials.


Assuntos
Aedes/microbiologia , Controle de Mosquitos/métodos , Mosquitos Vetores/microbiologia , Wolbachia/fisiologia , Animais , Feminino , Masculino , Cadeias de Markov , Modelos Biológicos , Dinâmica Populacional
7.
Phys Rev Lett ; 125(9): 097201, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32915598

RESUMO

Using first-principles transport calculations, we predict that the anisotropic magnetoresistance (AMR) of single-crystal Co_{x}Fe_{1-x} alloys is strongly dependent on the current orientation and alloy concentration. An intrinsic mechanism for AMR is found to arise from the band crossing due to magnetization-dependent symmetry protection. These special k points can be shifted towards or away from the Fermi energy by varying the alloy composition and hence the exchange splitting, thus allowing AMR tunability. The prediction is confirmed by delicate transport measurements, which further reveal a reciprocal relationship of the longitudinal and transverse resistivities along different crystal axes.

8.
Med Mycol ; 57(2): 256-259, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29471422

RESUMO

Histoplasma capsulatum var. duboisii (Hcd) infections have been well documented to cause chronic granulomatous disease, mainly involving the skin of baboons and humans in African countries primarily. This retrospective study classified the subspecies of Histoplasma and developed a phylogenetic tree utilizing DNA sequences extracted from formalin-fixed, paraffin embedded (FFPE) tissues from 9 baboons from a research colony in Texas histologically diagnosed with Hcd. Based on sequence analysis of ITS-2, Tub-1, and ARF, Hcd isolated from the archived samples closely aligns with the African clade and has 88% sequence homology with a sample isolated from an individual in Senegal.


Assuntos
Histoplasma/classificação , Histoplasma/isolamento & purificação , Histoplasmose/veterinária , Papio/microbiologia , Filogenia , Doenças dos Primatas/microbiologia , África/epidemiologia , Animais , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Formaldeído , Genes Fúngicos/genética , Histoplasma/genética , Histoplasmose/epidemiologia , Histoplasmose/microbiologia , Epidemiologia Molecular , Inclusão em Parafina/veterinária , Doenças dos Primatas/epidemiologia , Estudos Retrospectivos , Análise de Sequência de DNA , Texas/epidemiologia
9.
Nutr Metab Cardiovasc Dis ; 29(1): 23-29, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30527352

RESUMO

BACKGROUND AND AIMS: Pro-Neurotensin (NT), a stable surrogate parameter of NT, has recently been introduced as a peptide predicting the development of obesity, diabetes mellitus, cardiovascular diseases, and cardiovascular mortality. However, regulation of Pro-NT in gestational diabetes mellitus (GDM) remains uninvestigated. METHODS AND RESULTS: Pro-NT was quantified in 74 women with GDM, 74 healthy, gestational age-matched, pregnant controls, as well as in a second cohort comprising of 74 healthy, non-pregnant control women, using a chemiluminometric sandwich immunoassay. Pro-NT was correlated to measures of obesity, hypertension, glucose and lipid metabolism, renal function, and inflammation. Mean ± standard deviation of circulating Pro-NT levels were not significantly different in women with GDM (100.2 ± 75.7 pmol/l) as compared to healthy, pregnant controls (103.2 ± 37.4 pmol/l) and healthy, non-pregnant female controls (105.9 ± 38.9 pmol/l) (p = 0.661). Homeostasis model assessment of insulin resistance (HOMA-IR) and creatinine positively correlated with serum Pro-NT in multivariate regression analysis. In contrast, free fatty acids (FFA) were inversely correlated with circulating Pro-NT. Results sustained adjustment for pregnancy status. CONCLUSIONS: Circulating Pro-NT is not independently associated with GDM, but is with HOMA-IR, creatinine, and FFA even after adjustment for pregnancy status.


Assuntos
Diabetes Gestacional/sangue , Neurotensina/sangue , Precursores de Proteínas/sangue , Biomarcadores/sangue , Glicemia/análise , Estudos de Casos e Controles , Creatinina/sangue , Estudos Transversais , Diabetes Gestacional/diagnóstico , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Insulina/sangue , Resistência à Insulina , Gravidez
10.
Insect Mol Biol ; 27(6): 796-807, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29989657

RESUMO

Wolbachia influence the fitness of their invertebrate hosts. They have effects on reproductive incompatibility and egg production. Although the former are well characterized, the mechanistic basis of the latter is unclear. Here, we investigate whether apoptosis, which has been implicated in fecundity in model insects, influences the interaction between fecundity and Wolbachia in the planthopper Laodelphax striatellus. Wolbachia-infected females produced about 30% more eggs than uninfected females. We used the terminal deoxyribonucleotidyl transferase (TDT)-mediated dUTP-digoxigenin nick end labeling staining to visualize apoptosis. Microscopic observations indicated that the Wolbachia strain wStri increased the number of ovarioles that contained apoptotic nurse cells in both young and aged adult females. The frequency of apoptosis was much higher in the infected females. The increased fecundity appeared to be a result of apoptosis of nurse cells, which provide nutrients to the growing oocytes. In addition, cell apoptosis inhibition by caspase messenger RNA interference in Wolbachia-infected L. striatellus markedly decreased egg numbers. Together, these data suggest that wStri might enhance fecundity by increasing the number of apoptotic cells in the ovaries in a caspase-dependent manner. Our findings establish a link between Wolbachia-induced apoptosis and egg production effects mediated by Wolbachia, although the way in which the endosymbiont influences caspase levels remains to be determined.


Assuntos
Apoptose , Caspases/metabolismo , Hemípteros/fisiologia , Wolbachia/fisiologia , Sequência de Aminoácidos , Animais , Caspases/genética , Feminino , Fertilidade , Aptidão Genética , Hemípteros/microbiologia , Ovário/microbiologia , Ovário/fisiologia
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