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Biology subjects

Tatsuoka, C.

Publications and source records attributed to Tatsuoka, C..

3 recordsLinked to original sources

Fractions strategy differences in those born extremely preterm

IntroductionTo investigate the effects of different strategies and cognitive load we explored brain hemodynamic responses associated with the use of different strategies to solve subtraction of fractions. We focused on those born extremely preterm (EPT; <28 weeks gestation) as they are known to have cognitive challenges and struggle with mathematics. We also included a group of full-term (FT) peers for comparison. MethodsFunctional MRI was acquired while the participants mentally solved fraction equations using either a strategy based on improper or mixed fractions. Different fraction item types were given, which affected respective required cognitive loads per strategy. Diffusion and T1-weighted structural images were also acquired. ResultsThe EPT and FT groups differed in terms of task-related hemodynamic responses. Functional group differences were greatest when strategies were applied to item types that result in high cognitive load. Other findings showed reduced white and grey matter volume and reduced white matter connectivity in widespread areas in the EPT group compared to the FT group. ConclusionThe understanding of function and structure presented here may help inform pedagogical practices by allowing for tailoring of mathematical education through identifying suitable strategy adoption that depends on item type, to circumvent weaknesses in cognitive skills.

neuroscience↗

Increased glucose availability sensitizes pancreatic cancer to chemotherapy

Pancreatic cancer (Pancreatic Ductal Adenocarcinoma; PDAC) is highly resistant to chemotherapy. Effective alternative therapies have yet to emerge, leaving chemotherapy as the best available systematic treatment. The discovery of safe and available adjuncts that improve chemotherapeutic efficacy would potentially improve survival outcomes. We show that a hyperglycemic state enhances the efficacy of conventional single- and multi-agent chemotherapies against PDAC. Molecular analyses of tumors exposed to relatively high glucose levels revealed that a key metabolic pathway, glutathione biosynthesis, is diminished and underlies chemo-sensitization by enhancing oxidative injury to cancer cells. Inhibition of this pathway under normal conditions phenocopied a hyperglycemic state by enhancing chemotherapeutic efficacy in mouse PDAC, while rescuing the pathway under high glucose abrogated the anti-tumor effects observed with chemotherapy.

cancer biology↗

Fascicles split or merge every ~560 microns within the human cervical vagus nerve

1Vagus nerve stimulation (VNS) is FDA approved for stroke rehabilitation, epilepsy, and depression; however, the vagus functional anatomy underlying the implant is poorly understood. We used microCT to quantify fascicular structure and neuroanatomy within human cervical vagus nerves. Fascicles split or merged every ~560 m (17.8 {+/-} 6.1 events/cm). The high degree of fascicular splitting and merging in humans may explain the clinical heterogeneity in patient responses.

neuroscience↗