Influence of brain-derived neurotrophic factor on pathfinding of dentate granule cell axons, the hippocampal mossy fibers

Mossy fibers, the dentate granule cell axons, are generated throughout an animal's lifetime. Mossy fiber paths and synapses are primarily restricted to the stratum lucidum within the CA3 region. Brain-derived neurotrophic factor (BDNF), a neurotrophin family protein that activates Trk neurotrophin receptors, is highly expressed in the stratum lucidum in an activity-dependent manner. The addition of a Trk neurotrophin receptor inhibitor, K252a, to cultured hippocampal slices induced aberrant extension of mossy fibers into ectopic regions. BDNF overexpression in granule cells ameliorated the mossy fiber pathway abnormalities caused by a submaximal dose of K252a. A similar rescue was observed when BDNF was expressed in CA3 pyramidal cells, most notably in mossy fibers distal to the expression site. These findings are the first to clarify the role of BDNF in mossy fiber pathfinding, not as an attractant cue but as a regulator, possibly acting in a paracrine manner. This effect of BDNF may be as a signal for new fibers to fasciculate and extend further to form synapses with neurons that are far from active BDNF-expressing synapses. This mechanism would ensure the emergence of new independent dentate gyrus-CA3 circuits by the axons of new-born granule cells

Predictors of Hypotension after Adrenalectomy for Pheochromocytoma

The management of blood pressure is a significant concern for surgeons and anesthesiologists performing adrenalectomy for pheochromocytoma. We evaluated clinical factors in pheochromocytoma patients to identify the predictors of postoperative hypotension. The medical records of patients who underwent adrenalectomy for pheochromocytoma between 2001 and 2017 were retrospectively reviewed and clinical and biochemical data were evaluated. Of 29 patients, 13 patients needed catecholamine support in the perisurgical period while 16 patients did not. There were significant differences in median age, tumor size, and blood pressure drop (maxmin) between the 2 groups (68 vs 53 years old, p=0.045; 50 vs 32 mm diameter, p=0.022; 110 vs 71 mmHg, p=0.015 respectively). In univariate logistic analysis, age > 65.5 years, tumor size > 34.5 mm, urine metanephrine > 0.205 mg/day and urine normetanephrine > 0.665 mg/day were significant predictors of prolonged hypotension requiring postoperative catecholamine support. Tumor size and urine metanephrine and urine normetanephrine levels were correlated with postoperative hypotension. These predictors may help in the safe perioperative management of pheochromocytoma patients treated with adrenalectomy

Living alone is associated with depression among the elderly in a rural community in Japanp syg_402 179..185

Abstract Aim: This study aimed to investigate factors associated with depression in a sample of elderly Japanese individuals in a rural community and to examine differences among factors associated with individuals living alone or living with others. Methods: Using a population-based sample from rural Japan, we assessed a total of 1552 participants aged 65 years or older by mailing a survey and evaluating responses based on the Geriatric Depression Scale. Factors associated with depression were also examined. Results: We received 964 valid responses. Depressed subjects comprised 20.5% of the sample. Living alone was significantly related to depression. In individuals living alone, depression was associated with loss of appetite, suicidal ideation, financial strain, and worries in life. However, multiple linear regression analyses revealed that the influence of living alone was negated by having a good social support system. Conclusion: These findings confirm that living alone is an important factor in depression among the elderly in a rural part of Japan. Results also confirm what others have found in Western cultures: high levels of social support, awareness of receiving social support, and willingness to receive assistance may reduce the risk of depression

Feasibility of Laparoscopic Radical Cystectomy in Elderly Patients: A Comparative Analysis of Clinical Outcomes in a Single Institution

Laparoscopic radical cystectomy (LRC) is a standard surgical treatment for muscle-invasive bladder cancer and high-risk non-muscle-invasive bladder cancer. LRC is a less invasive modality than conventional open surgery. Therefore, even elderly patients with invasive bladder cancer may be candidates for LRC. In this study, a comparative analysis of perioperative/oncological outcomes between elderly patients and younger patients who underwent LRC was performed to assess the feasibility of LRC in elderly patients. Sixty-eight consecutive patients who underwent LRC between October 2013 and March 2018 were enrolled and stratified into those younger than 75 years (n=37) and those ≥ 75 years old (n=31). The median follow-up period was 28.2 months. The preoperative and operative parameters and complications were similar in both groups. The 2-year overall survival (OS) was 64.4% in the younger vs. 76.4% in the elderly group (p=0.053), cancer-specific survival (CSS) was 79.3% vs. 81.7% (p=0.187), and recurrence-free survival (RFS) was 58.2% vs. 75.7% (p=0.174), respectively. No significant differences were observed in OS, CSS, or RFS between the groups. No significant differences were found between the groups with respect to peri-surgical/oncological outcomes. We conclude that LRC is feasible in elderly patients

Synthesis of MDI and PCL-diol-based polyurethanes containing [2] and [3]rotaxanes and their properties

We have successfully synthesized novel polyurethanes where PU1 contains a [3]rotaxane that consists of N-3,5-di-tert-butylbenzyl-N-3-hydroxypropylammonium hexafluorophosphate (AOH1) and N,N′-Dimethyl-N,N′-bis(dibenzo-24-crown-8)-terephthalamide (BisC) as well as PU2 contains a [2]rotaxane that consists of AOH1 and dibenzo-24-crown-8 ether. Diphenylmethanediisocyanate (MDI), 1,4-butanediol (BD) and poly(ε-caprolactone)diol (PCL) were used as an isocyanate, chain expander, and soft segment, respectively. A polyurethane without any rotaxane structures (PU0) were also prepared as a reference polymer. The existence of the rotaxanes in the polyurethanes was confirmed by 1H NMR spectroscopy and TGA measurement. ATR-FT-IR spectral measurement revealed that the rotaxanes disturb the formation of hydrogen bonding between the polyurethane chains. From the DSC result, the rotaxanes retard the recrystallization of the PCL unit whereas no influence on the glass transition temperatures of the polyurethanes was observed. The retarding effect appeared remarkably with PU1. These thermal behaviors of the polyurethanes were also supported by viscoelastic measurement. In tensile test, the tensile strength and break of strain of PU1 were larger than those of PU2