Robust differentiation of human pluripotent stem cells into Schwann cells.

Research into Schwann cell (SC)-related diseases has been hampered by the difficulty of obtaining human-derived SCs, which have limited proliferative capacity. This has resulted in a delay in progress in drug discovery and cell therapy targeting SCs. To overcome these limitations, we developed a robust method for inducing the differentiation of human induced pluripotent stem cells (hiPSCs) into SCs. We established hiPSC lines and successfully generated high-purity Schwann cell precursors (SCPs) from size-controlled hiPSC aggregates by precisely timed treatment with our proprietary enzyme solution. Such SCPs were successfully expanded and further differentiated into myelin basic protein (MBP) expressing SC populations when treated with an appropriate medium containing dibutyryl-cAMP (db-cAMP). These differentiated cells secreted factors that induced neurite outgrowth in vitro. Our method allows for the efficient and stable production of SCPs and SCs from hiPSCs. This robust induction and maturation method has the potential to be a valuable tool in drug discovery and cell therapy targeting SC-related diseases.

Lessons from COVID-19's impact on medical tourism in Cambodia.

Making medical tourism a more valuable healthcare system is a significant public health issue. However, little discussion has been conducted on what lessons can be learned from the impact of COVID-19 on medical tourism. This study aimed to discuss the issues and barriers faced by patients unable to seek medical tourism, and the medical care experience at private general hospital in capital, Cambodia. First, when patients seeking medical tourism were unable to go abroad due to the pandemic or other reasons, some of them could not easily visit domestic health care facilities. Second, even if patients received medical care in the home country's hospitals due to the interruption of medical tourism, sharing the patient's medical information between domestic and overseas medical institutions was difficult. The third problem in medical tourism is that dependence on overseas medical resources might hinder the development of medical professionals, facilities, and other environments in the country of origin. This experience revealed the need to encourage patients who were unable to undertake medical tourism to visit domestic medical facilities, make efforts to share patient information across countries, and to invest in developing each department in domestic hospitals. Support for patients who are unable to undertake medical tourism is urgently needed.

[Predictive Factors for Gastrointestinal Bleeding Following Hemorrhagic Stroke: A Hospital-Based Cohort Study].

BACKGROUND AND PURPOSE: Gastrointestinal bleeding is an important complication in the acute phase of hemorrhagic stroke. In this study, we aimed to identify the risk factors for gastrointestinal bleeding in patients with hemorrhagic stroke despite the administration of antiulcer drugs. METHODS: We conducted a retrospective cohort study of our hemorrhagic stroke cases. We analyzed the background factors associated with gastrointestinal bleeding in the study population and their outcomes. RESULTS: The study included 837 patients: 598 with intracerebral hemorrhages and 239 with subarachnoid hemorrhages. Among them, 22 patients developed gastrointestinal bleeding. Intraventricular hemorrhage (P=0.0019) and ongoing oral anticoagulant use (P=0.0177) were significantly associated with gastrointestinal bleeding. Gastrointestinal bleeding was significantly associated with severe disability at discharge (P=0.0333) and number of days of hospitalization (P=0.0190). CONCLUSIONS: The risk factors of poorly controlled gastrointestinal bleeding during the acute phase of hemorrhagic strokes were intraventricular hemorrhage and use of anticoagulant drugs. Patients with a high risk for gastrointestinal bleeding need to be identified and to be given effective prophylactic therapy. (Received October 12, 2017; Accepted March 29, 2018; Published August 1, 2018).

NAD-Malic Enzyme Affects Nitrogen Fixing Activity of Bradyrhizobium japonicum USDA 110 Bacteroids in Soybean Nodules.

The NAD(+)-dependent malic enzyme (DME) has been reported to play a key role supporting nitrogenase activity in bacteroids of Sinorhizobium meliloti. Genetic evidence for a similar role in Bradyrhizobium japonicum USDA110 was obtained by constructing a dme mutant. Soybean plants inoculated with a dme mutant did not show delayed nodulation, but formed small root nodules and exhibited significant nitrogen-deficiency symptoms. Nodule numbers and the acetylene reducting activity per nodule as a dry weight value 14 and 28 days after inoculation with the dme mutant were comparable to those of plants inoculated with wild-type B. japonicum. However, shoot dry weight and acetylene reducting activity per nodule decreased to ca. 30% of the values in plants with wild-type B. japonicum. The sucrose and organic acid (malate, succinate, acetate, α-ketoglutarate and lactate) contents of the nodules were investigated. Amounts of sucrose, malate and a-ketoglutarate increased on inoculation with the dme mutant, suggesting that the decreased DME and nitrogenase activities in the bacteroids resulted in a reduction in the consumption of these respiratory metabolites by the nodules. The data suggest that the DME activity of B. japonicum bacteroids plays a role in nodule metabolism and supports nitrogen fixation.