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Abstract

In this commentary, we highlight some of the pressing choices and sacrifices we must make in medical education during the COVID-19 pandemic.  相似文献   
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Abstract

Background: An association between sexually transmitted diseases (STDs) and occurrence of head and neck cancer (HNC) is proposed.

Aims/objectives: We aimed to determine the association between selected STDs (syphilis, gonorrhoea, HIV) and HNC.

Materials and methods: Patients diagnosed with HNC in Denmark between 1978 and 2014 identified through the Danish Cancer Registry were included. Patients were age- and sex-matched in a 1:10 ratio with general population controls. Uni- and multivariate analyses were performed using the Cox regression model to assess the correlation between STD and HNC.

Results: A total of 39,405 HNC patients (63% men; 63.0 years at HNC diagnosis) and 393,238 controls were included. STD in HNC patients was 0.27%, vs. 0.11% in controls. Patients with cancer of the upper airways had a significantly higher prevalence of an STD prior to the HNC compared to controls. Most HNC patients with a prior STD (64.1%) developed the HNC within five years after the STD diagnosis.

Conclusions: Although the studied STDs are rare, patients with cancer of the upper aerodigestive tract more commonly had a previous diagnosis of STD compared to controls. The study promotes the hypothesis that a causal link exists between STD and HNC.  相似文献   
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Alzheimer's disease (AD) is a common dementia affecting a vast number of individuals and significantly impairing quality of life. Despite extensive research in animal models and numerous promising treatment trials, there is still no curative treatment for AD. Astrocytes, the most common cell type of the central nervous system, have been shown to play a role in the major AD pathologies, including accumulation of amyloid plaques, neuroinflammation, and oxidative stress. Here, we show that inflammatory stimulation leads to metabolic activation of human astrocytes and reduces amyloid secretion. On the other hand, the activation of oxidative metabolism leads to increased reactive oxygen species production especially in AD astrocytes. While healthy astrocytes increase glutathione (GSH) release to protect the cells, Presenilin-1-mutated AD patient astrocytes do not. Thus, chronic inflammation is likely to induce oxidative damage in AD astrocytes. Activation of NRF2, the major regulator of cellular antioxidant defenses, encoded by the NFE2L2 gene, poses several beneficial effects on AD astrocytes. We report here that the activation of NRF2 pathway reduces amyloid secretion, normalizes cytokine release, and increases GSH secretion in AD astrocytes. NRF2 induction also activates the metabolism of astrocytes and increases the utilization of glycolysis. Taken together, targeting NRF2 in astrocytes could be a potent therapeutic strategy in AD.  相似文献   
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