Perceptual manifestations of auditory modulation during speech planning

Abstract

Recent studies have provided electrophysiological evidence that the auditory system's response to externally generated auditory stimuli during speech planning is modulated in comparison to its responses to identical stimuli during no-speaking control conditions. In this study, we examined whether such neural modulations during speech planning result in measurable perceptual modulations. In a two-interval forced choice intensity discrimination paradigm, participants were asked to judge the intensity of a standard tone (with constant intensity), played during a fixation period, relative to the intensity of a comparison tone (with varying intensity), played during speech planning or during no-speaking conditions (silent reading and passive listening). Psychometric functions were fitted to participants' responses in each condition; psychometric functions were used to calculate the point of subjective equality (as a measure of perceptual threshold) and the slope of the psychometric functions (as a measure of perceptual uncertainty). We found that the point of subjective equality in the speaking condition was statistically significantly larger than that in the no-speaking conditions. In addition, slope values in the speaking and listening conditions were statistically significantly smaller than slope value in the silent reading condition. Together, these results suggest that previously reported electrophysiological modulations of the auditory system during speech planning may have perceptual manifestations, such as increases in perceptual thresholds and uncertainty of perceptual thresholds in an intensity discrimination task.

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The Carotenogenic Dunaliella salina CCAP 19/20 Produces Enhanced Levels of Carotenoid under Specific Nutrients Limitation

Dunaliella salina is the popular microalga for β-carotene production. There is still a growing demand for the best strain identification and growth conditions optimization for maximum carotenoids production. Some strains are noncarotenogenic while other strains may respond differently to applied growth conditions and produce enhanced carotenoid levels. This study tested the carotenogenic ability of Dunaliella salina CCAP 19/20 under sixteen stress conditions and certain biochemical changes in response to specific stress were investigated. This study identified the above strain as carotenogenic, which produces maximum carotenoids under high light (240 μmol photons m−2 sec−1) when combined nitrogen and micronutrients (Cu or CuMn) were limited. Based on the intensity of extracted ions chromatograms, lutein (m/z 568.4357) appears as the major carotenoid followed by β-carotene (m/z 536.4446) and α-carotene (m/z 536.4435). A polypeptide of 28.3 kDa appeared while another polypeptide of 25.5 kDa disappeared in stress cells as compared to noncarotenogenic cells. Expression levels of antioxidative-enzyme superoxide dismutase-1 (SOD1, H2O2-resistant) remained identical, while the prominent H2O2-sensitive isoforms SOD2 and SOD3 were downregulated during carotenogenic conditions. Overall, increased carotenoids levels might be due to the response of differential expression of specific polypeptides and retention of H2O2-resistant SOD, which eventually might help the organism to thrive in the tested stress conditions.

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The Involvement of Arginase and Nitric Oxide Synthase in Breast Cancer Development: Arginase and NO Synthase as Therapeutic Targets in Cancer

It is well established that, during development of malignancies, metabolic changes occur, including alterations of enzyme activities and isoenzyme expression. Arginase and nitric oxide (NO) synthase (NOS) are two of those enzymes considered to be involved in tumorigenesis. The goal of this article was to study the involvement of arginase and NOS in the development of different stages of breast cancer. Our results have shown that human serum arginase activity and NO (resp., and NOS activity) and polyamines quantities increased in parallel with cancer stage progression and decreased after neoadjuvant chemotherapy. For breast cancer, the only isoenzyme of arginase expressed in serum before and after chemotherapy was in a cationic form. The data of Lineweaver-Burk plot with a value of 2 mM was calculated, which is characteristic for human liver type isoform of arginase. During electrophoresis at pH 8.9, the enzyme exhibited high electrophoretic mobility and was detected near the anode. The presented results demonstrated that arginase in human serum with breast cancer and after chemotherapy is not polymorphic. We suggest that arginase and NOS inhibition has antitumor effects on cancer development, as it can inhibit polyamines and NO levels, a precursor of cancer cell proliferation, metastasis, and tumor angiogenesis.

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Employment status and termination among survivors of pediatric brain tumors: a cross-sectional survey

Abstract

Background

Some childhood cancer survivors experience employment difficulties. This study aimed to describe pediatric brain-tumor survivors' employment status.

Methods

A cross-sectional, observational study was conducted, with questionnaires distributed to 101 pediatric brain-tumor survivors (aged 15 years or older) and their attending physicians from nine institutions in Japan. We compared category and time-series histories for participants' first-time employment using national census information. Factors related to delayed employment or early employment termination were examined using survival-time analyses.

Results

Excluding students and homemakers, 38 brain-tumor survivors (median age 27 years, with 15 years since diagnosis) were of working age. Of these, 12 (32%) were unemployed and 9 (24%) had never been employed. First-time employment occurred later for brain-tumor survivors than the general population, particularly in those with lower educational levels. The number of brain-tumor survivors whose first job was terminated within the first year was higher than that for the general population, particularly in male survivors and germ cell-tumor survivors. Brain-tumor survivors described their working patterns (irregular), job types (specialist or professional), reasons for early termination (unsuitable job), and thoughts about working (they wished to serve their communities but lacked confidence).

Conclusion

Brain-tumor survivors are associated with high unemployment rates and multiple unemployment-related factors. Education and welfare systems should identify individual methods of social participation for this group.

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Capturing intra-tumor genetic heterogeneity by de novo mutation profiling of circulating cell-free tumor DNA: a proof-of-principle

Ann Oncol 2014; 25: 1729–1735 (doi: 10.1093/annonc/mdu239)

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Mapping unmet supportive care needs, quality-of-life perceptions and current symptoms in cancer survivors across the Asia-Pacific region: results from the International STEP Study

Ann Oncol 2017; 28: 2552–2558 (doi:10.1093/annonc/mdx350)

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Activation of AhR with nuclear IKKα regulates cancer stem-like properties in the occurrence of radioresistance

Activation of AhR with nuclear IKKα regulates cancer stem-like properties in the occurrence of radioresistance

Activation of AhR with nuclear IKKα regulates cancer stem-like properties in the occurrence of radioresistance, Published online: 30 April 2018; doi:10.1038/s41419-018-0542-9

Activation of AhR with nuclear IKKα regulates cancer stem-like properties in the occurrence of radioresistance

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