Voice symptoms in teachers during distance teaching: a survey during the COVID-19 pandemic in Finland.

PURPOSE: Due to the coronavirus disease of 2019 (COVID-19), teachers during the pandemic have had to adapt to online teaching at short notice. This study aims to investigate the voice symptoms and their environmental risk factors as well as the work ability associated with distance teaching and to compare these with symptoms in previous contact teaching. METHODS: We conducted a survey of 121 primary and secondary school teachers across Finland. The survey was advertised online through social media and the replies collected from voluntarily participating teachers. RESULTS: During distance teaching vocal symptoms appeared less often than in school with 71% teachers experiencing them in regular teaching and 44% in distance teaching, VHI result decreased from 7.88 in school teaching to 4.58 in distance teaching. Acoustic conditions were reported to be more suitable in distance teaching with 73% of teachers finding them adequate during distance teaching in comparison to 46% for those in regular teaching. Background noise was the most disturbing factor for a teacher's voice in the classroom and in distance teaching and this was even more conspicuous in the classroom. Also, subjectively experienced poor indoor air quality at school influenced the voice negatively. Further, voice problems were associated with increased subjective stress levels and reduced ability to work. CONCLUSION: Distance teaching has affected teachers' voices in a positive way compared with regular teaching. This difference is likely to be due to better acoustics and indoor air quality in distance teaching conditions.

Discovery of novel drug sensitivities in T-PLL by high-throughput ex vivo drug testing and mutation profiling.

T-cell prolymphocytic leukemia (T-PLL) is a rare and aggressive neoplasm of mature T-cells with an urgent need for rationally designed therapies to address its notoriously chemo-refractory behavior. The median survival of T-PLL patients is <2 years and clinical trials are difficult to execute. Here we systematically explored the diversity of drug responses in T-PLL patient samples using an ex vivo drug sensitivity and resistance testing platform and correlated the findings with somatic mutations and gene expression profiles. Intriguingly, all T-PLL samples were sensitive to the cyclin-dependent kinase inhibitor SNS-032, which overcame stromal-cell-mediated protection and elicited robust p53-activation and apoptosis. Across all patients, the most effective classes of compounds were histone deacetylase, phosphoinositide-3 kinase/AKT/mammalian target of rapamycin, heat-shock protein 90 and BH3-family protein inhibitors as well as p53 activators, indicating previously unexplored, novel targeted approaches for treating T-PLL. Although Janus-activated kinase-signal transducer and activator of transcription factor (JAK-STAT) pathway mutations were common in T-PLL (71% of patients), JAK-STAT inhibitor responses were not directly linked to those or other T-PLL-specific lesions. Overall, we found that genetic markers do not readily translate into novel effective therapeutic vulnerabilities. In conclusion, novel classes of compounds with high efficacy in T-PLL were discovered with the comprehensive ex vivo drug screening platform warranting further studies of synergisms and clinical testing.

Novel drug candidates for blast phase chronic myeloid leukemia from high-throughput drug sensitivity and resistance testing.

Chronic myeloid leukemia in blast crisis (CML BC) remains a challenging disease to treat despite the introduction and advances in tyrosine kinase inhibitor (TKI) therapy. In this study we set out to identify novel candidate drugs for CML BC by using an unbiased high-throughput drug testing platform. We used three CML cell lines representing different types of CML blast phases (K562, EM-2 and MOLM-1) and primary leukemic cells from three CML BC patients. Profiling of drug responses was performed with a drug sensitivity and resistance testing platform comprising 295 anticancer agents. Overall, drug sensitivity scores and the drug response profiles of cell line and primary cell samples correlated well and were distinct from other types of leukemia samples. The cell lines were highly sensitive to TKIs and the clinically TKI-resistant patient samples were also resistant ex vivo. Comparison of cell line and patient sample data identified new candidate drugs for CML BC, such as vascular endothelial growth factor receptor and nicotinamide phosphoribosyltransferase inhibitors. Our results indicate that these drugs in particular warrant further evaluation by analyzing a larger set of primary patient samples. The results also pave way for designing rational combination therapies.

Intracellular high energy metabolite depletion and cell membrane injury with antioxidant enzymes during oxidant exposure in vitro.

We compared oxidant-induced intracellular adenine nucleotide catabolism and cell membrane injury in 4 different human cell types. Responses to oxidant exposure were correlated with endogenous antioxidant enzyme activities in these cells. Blood monocytes, amniotic fibroblasts, umbilical vein endothelial cells in primary culture, and transformed bronchial epithelial cells (BEAS 2B) were exposed to 0.1-5 mM hydrogen peroxide (H2O2) for 4 h. Some experiments were conducted in cells pretreated with 3-amino 1:2,4-triazole (ATZ) to inactivate catalase or with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) to inactivate glutathione (GSH) reductase. Depletion of adenine nucleotides and accumulation of their catabolic products (hypoxanthine, xanthine and uric acid) occurred to varying extent, monocytes being the most resistant. There was a mutual relationship between catalase and GSH reductase activities and maintenance of cellular adenine nucleotide levels during H2O2 exposure. GSH reductase inhibition rendered BEAS 2B cells susceptible to lytic injury by H2O2, assessed by release of lactate dehydrogenase and intact nucleotides into the medium, there was no correlation between these markers of such injury and endogenous antioxidant enzymes. We conclude that adenine nucleotide depletion and nucleotide catabolite accumulation relate closely with the antioxidant enzyme activities, whereas the lack of a similar correlation between the enzyme levels and markers of lytic cell injury suggest that intracellular antioxidant enzymes do not protect cells from membrane damage due to extracellular oxidants.

Catalase and glutathione reductase protection of human alveolar macrophages during oxidant exposure in vitro.

Because alveolar macrophages generate and release reactive oxygen metabolites but also contain antioxidative enzymes, they have the potential of either damaging or protecting tissues. We investigated the relative role of the hydrogen peroxide (H2O2)-scavenging antioxidative enzymes in H2O2 disposal and cell protection using freshly isolated (5 h ex vivo) and overnight (24 h ex vivo) cultured human alveolar macrophages. Cell protection was assessed on the basis of maintenance of cellular high-energy phosphates, leakage of intact nucleotides into the extracellular medium, and appearance of the nucleotide catabolic products xanthine, hypoxanthine, and uric acid. To investigate the relative importance of catalase and the glutathione redox cycle, the experiments were conducted in cells pretreated with amino-triazole (ATZ) to inactivate catalase or with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) to inactivate glutathione reductase. Catalase, glutathione peroxidase, and glutathione reductase activities did not change significantly during overnight culture of the cells. Both freshly isolated and cultured cells consumed exogenous H2O2 mainly by the catalase-dependent pathway. When the cells were exposed to H2O2 (100 microM), catalase and the glutathione redox cycle equally participated in maintaining cellular high-energy nucleotides. However, when cultured cells were exposed to formylated peptide (FMLP) (10(-7) M), the glutathione redox cycle was responsible for the maintenance of high-energy nucleotides. Furthermore, in both exposures, the glutathione redox cycle was more important in maintaining cell membrane integrity and preventing nucleotide leakage from the cells. Immunocytochemical labeling showed that catalase was primarily localized in the peroxisomal compartment of these cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Mitochondrial superoxide dismutase induction does not protect epithelial cells during oxidant exposure in vitro.

The significance of manganese superoxide dismutase (MnSOD) induction in cells and tissues during oxidant stress is still poorly understood. In this study, transformed human bronchial epithelial cells (BEAS 2B) were treated with interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), or with combination of these cytokines (10 ng/ml concentrations) for 48 or 72 h and exposed to selected oxidants. TNF-alpha and IFN-gamma + TNF-alpha combination resulted in a marked increase of MnSOD protein and MnSOD activity. When cells pretreated with the cytokines were exposed to hyperoxia (95% O2, 72 h), menadione (5-50 microM, 4 h), or H2O2 (0.5 and 5 mM, 4 h), in all cases IFN-gamma and TNF-alpha enhanced oxidant-related cell injury. The effect was most significant with cells pretreated with a combination of IFN-gamma and TNF-alpha. Antioxidant enzymes such as total SOD, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase did not change significantly during the cytokine treatment. Catalase activity was not changed by IFN-gamma or TNF-alpha but it decreased significantly (34%) in IFN-gamma + TNF-alpha-treated cells. Free radical generation was not changed by these cytokines in acute (30 min) experimental conditions or after 48-h treatment. These results suggest that cytokine-induced MnSOD does not protect bronchial epithelial cells against endogenously or exogenously generated oxidants in vitro. In fact, cells that contained the highest MnSOD activity were the most sensitive to subsequent oxidant damage.