Long-term exposure to methylmercury and psychiatric symptoms in residents of Minamata, Japan

Introduction: It is well-known that prenatal or postnatal exposure to methylmercury can produce neurological signs in adults and children, exemplified by a case of large-scale poisoning in Minamata, Japan, in the 1950s. However, evidence regarding whether pre- or postnatal exposure to methylmercury causes psychiatric symptoms (e.g., impairment of intelligence and mood and behavioral dysfunction) is still limited-excluding cases of fetal Minamata disease patients. Methods: We evaluated the effects of pre- or postnatal exposure to methylmercury on psychiatric symptoms using data derived from a 1971 population-based survey in Minamata and neighboring communities. We adopted residential areas as an exposure indicator and psychiatric symptoms as the outcome. Then, we estimated the adjusted prevalence odds ratio (POR) and confidence interval (Cl) of psychiatric symptoms in relation to residential area. Results: There were 904 participants in Minamata (high exposure area), 1700 in Goshonoura (middle exposure area), and 913 in Ariake (low exposure area). Compared to the Ariake area, participants in the Minamata area manifested psychiatric symptoms more frequently: PORs for impairment of intelligence and mood and behavioral dysfunction were 5.2 (95% Cl: 3.7-7.3) and 4.4 (95% Cl: 2.9-6.7), respectively. Furthermore, participants with psychiatric symptoms in the Minamata area more frequently had neurological signs. Peaks in prevalence of psychiatric symptoms occurred around age 20 and in older age adults in the area. These findings did not change when we excluded those who had been officially certified as Minamata disease patients by that time. Conclusions: The present study suggests a relationship between pre- or postnatal exposure to methylmercury and psychiatric symptoms among the general population in Minamata even after excluding officially certified patients

Human Hematopoietic Stem Cells Can Survive In Vitro for Several Months

We previously reported that long-lasting in vitro hematopoiesis could be achieved using the cells differentiated from primate embryonic stem (ES) cells. Thus, we speculated that hematopoietic stem cells differentiated from ES cells could sustain long-lasting in vitro hematopoiesis. To test this hypothesis, we investigated whether human hematopoietic stem cells could similarly sustain long-lasting in vitro hematopoiesis in the same culture system. Although the results varied between experiments, presumably due to differences in the quality of each hematopoietic stem cell sample, long-lasting in vitro hematopoiesis was observed to last up to nine months. Furthermore, an in vivo analysis in which cultured cells were transplanted into immunodeficient mice indicated that even after several months of culture, hematopoietic stem cells were still present in the cultured cells. To the best of our knowledge, this is the first report to show that human hematopoietic stem cells can survive in vitro for several months

The nuclear receptor hepatocyte nuclear factor 4α acts as a morphogen to induce the formation of microvilli

Microvilli are actin-based organelles found on apical plasma membranes that are involved in nutrient uptake and signal transduction. Numerous components, including ezrin/radixin/moesin (ERM) proteins, have been identified that link filamentous actins to transmembrane proteins, but the signals driving microvillus biogenesis are not known. In this study, we show that the conditional and/or ectopic expression of a nuclear receptor, hepatocyte nuclear factor 4α (HNF4α), triggers microvillus morphogenesis. We also demonstrate that HNF4α expression induces ERM-binding phosphoprotein 50 (EBP50) expression and that attenuation of EBP50 using RNA interference inhibits microvillus development. We conclude that HNF4α acts as a morphogen to trigger microvillus formation

Perioperative Clinical Course Variables Associated with Length of Hospital Stay after Primary Intracranial Meningioma Resection

The relationship between perioperative clinical course variables and postoperative length of hospital stay (LOS) in patients undergoing primary intracranial meningioma resection has not been fully elucidated. We therefore aimed to identify the perioperative clinical course variables that predict postoperative LOS in such patients. We retrospectively collected data concerning demographics, tumor characteristics, and perioperative clinical course variables in 76 patients who underwent primary intracranial meningioma resection between January 2010 and December 2019, and tested for associations with postoperative LOS. Univariate analyses showed that younger age, fewer days to postoperative initiation of standing/walking, preoperative independence in activities of daily living (ADL), and ADL independence one week after surgery were associated with shorter postoperative LOS. Multiple regression analyses with these factors identified that days to stand/walk initiation and ADL independence one week after surgery were associated with postoperative LOS. Based on these results, we conclude that rehabilitation programs that promote early mobilization and the early acquisition of independence may reduce postoperative LOS in patients who undergo primary intracranial meningioma resection

Association of elevated plasma B-type natriuretic peptide levels with paroxysmal atrial fibrillation in patients with nonobstructive hypertrophic cardiomyopathy

Objectives: To investigate the relationship between the plasma B-type natriuretic peptide (BNP) level and the occurrence of atrial fibrillation (AF) in nonobstructive hypertrophic cardiomyopathy (HCM) patients. Methods: Patients (n=97) were classified into chronic AF (CAF; n=14), paroxysmal AF (PAF; n=18) and normal sinus rhythm (NSR; n=65) groups. The plasma BNP values were analyzed with logarithmic transformation. Results: The PAF group showed significantly higher plasma BNP levels than the NSR group [mean (range; -1 SD and +1 SD); 248.3 (143.5, 429.5) vs. 78.2 (27.9, 218.8 ng/L), p Conclusions: The present study indicated that plasma BNP level is clinically useful for identification of nonobstructive HCM patients who have a risk of PAF.</p