Gfap‐positive radial glial cells are an essential progenitor population for later‐born neurons and glia in the zebrafish spinal cord

Radial glial cells are presumptive neural stem cells (NSCs) in the developing nervous system. The direct requirement of radial glia for the generation of a diverse array of neuronal and glial subtypes, however, has not been tested. We employed two novel transgenic zebrafish lines and endogenous markers of NSCs and radial glia to show for the first time that radial glia are essential for neurogenesis during development. By using the gfap promoter to drive expression of nuclear localized mCherry we discerned two distinct radial glial‐derived cell types: a major nestin+/Sox2+ subtype with strong gfap promoter activity and a minor Sox2+ subtype lacking this activity. Fate mapping studies in this line indicate that gfap+ radial glia generate later‐born CoSA interneurons, secondary motorneurons, and oligodendroglia. In another transgenic line using the gfap promoter‐driven expression of the nitroreductase enzyme, we induced cell autonomous ablation of gfap+ radial glia and observed a reduction in their specific derived lineages, but not Blbp+ and Sox2+/gfap‐negative NSCs, which were retained and expanded at later larval stages. Moreover, we provide evidence supporting classical roles of radial glial in axon patterning, blood–brain barrier formation, and locomotion. Our results suggest that gfap+ radial glia represent the major NSC during late neurogenesis for specific lineages, and possess diverse roles to sustain the structure and function of the spinal cord. These new tools will both corroborate the predicted roles of astroglia and reveal novel roles related to development, physiology, and regeneration in the vertebrate nervous system. GLIA 2016;64:1170–1189     

Abnormal sodium and potassium metabolism in orthostatic dysregulation in childhood

Serum sodium (Na) and potassium (K), 12-hr urine Na, K and Na/K ratio and fractional Na excretion rate (FENa) were examined in 142 children with orthostatic dysregulation (O.D.) aged 6 to 15 years. Serum K and FENa were significantly lower in children with O.D. than in normal children, conflicting with the results of low plasma renin activity and aldosterone concentration in children with O.D. which we had previously reported. This suggests that there might be excessive excretion of a mineralocorticoid other than aldosterone or that there might be abnormal regulation of Na and K metabolism by the renin-angiotensin-aldosterone system.     

Endoscopy in the diagnosis of small intestinal tumors

The importance of endoscopy in the diagnosis of small intestinal tumors was evaluated in 15 patients with small intestinal tumors treated in our hospital. Two tumors were benign, and 13 were malignant (carcinoma in 5 patients, malignant lymphoma in 5 and leiomyosarcoma in 3). The presence of lesions could be determined by X-rays before surgery, but definitive diagnoses were difficult. When preoperative endoscopy of the small intestine was possible accurate preoperative diagnoses could be made based on the endoscopic findings and biopsies taken under direct vision. Endoscopy is therefore very important for the diagnosis of small intestinal tumors. It is necessary to develop small intestinal endoscopes that are easier to insert.     

Physiological capacity of the reticuloendothelial system for the degradation of hemoglobin vesicles (artificial oxygen carriers) after massive intravenous doses by daily repeated infusions for 14 days

A hemoglobin vesicle (HbV; diameter 252 +/- 53 nm) or liposome-encapsulated Hb is an artificial oxygen carrier developed for use as a transfusion alternative, and its oxygen-transporting capacity has been well characterized, although critical physiological compartments for the Hb degradation after a massive infusion of HbV and the safety outcome remain unknown. In this study, we aimed to examine the compartments for its degradation by daily repeated infusions (DRI) of HbV, focusing on its influence on the reticuloendothelial system (RES). Male Wistar rats intravenously received the HbV suspension at 10 ml/kg/day for 14 consecutive days. The cumulative infusion volume (140 ml/kg) was equal to 2.5 times the whole blood volume (56 ml/kg). The animals tolerated the DRI well and survived, and body weights continuously increased. One day after DRI, hepatosplenomegaly occurred significantly through the accumulation of large amounts of HbV. Plasma clinical chemistry was overall normal, except for a transient elevation of lipid components derived from HbV. These symptoms subsided 14 days after DRI. Hemosiderin deposition and up-regulation of heme oxygenase-1 coincided in the liver and spleen but were not evident in the parenchyma of these organs. Furthermore, the plasma iron and bilirubin levels remained unchanged, suggesting that the heme-degrading capacity of the RES did not surpass the ability to eliminate bilirubin. In conclusion, phospholipid vesicles for the encapsulation of Hb would be beneficial for heme detoxification through their preferential delivery to the RES, a physiological compartment for degradation of senescent RBCs, even at doses greater than putative clinical doses.     

Process design for efficient and controlled drug incorporation into polymeric micelle carrier systems.

For the efficient and well-controlled incorporation of the anti cancer drug adriamycin (ADR) into the inner core of a thermo-responsive polymeric micelle carrier system, we have analyzed and optimized the incorporation procedure in this paper. A dialysis method was used for preparing the micelle solution and ADR incorporation simultaneously. Quantities of ADR and triethylamine (TEA) were varied and the effects of their quantities were analyzed. Solvent composition at the starting time of dialysis was also varied. The initial dialysis condition, solvent with 40% water, brought about the largest amount and yield of ADR incorporation. With the initial 40% water content, it was considered that the block polymers formed a micelle-like association with a swollen hydrophobic core. This swollen core may be suitable for a large amount of ADR incorporation, since this core, swollen by an organic solvent-water mixture, is expected to show a liquid-state character to allow ADR molecules entry into the cores. By starting the dialysis procedure at this 40% water content, this swollen core suitable for the ADR incorporation is considered to be maintained for a much longer period than a case starting with a polymer-ADR solution in a solvent with a water content of less than 40%, and, therefore, ADR is expected to be incorporated efficiently. Preparation temperature of 20-25 degrees C was found to provide the most effective ADR incorporation in this thermo-responsive polymeric micelle system. These results indicate that the efficient incorporation of ADR can be achieved in consideration of the dynamic micelle formation and drug incorporation processes.     

The beneficial effects of lymphocytapheresis for treatment of nephrotic syndrome.

A considerable permeability factor (or factors) derived from circulating T cells has a crucial role in proteinuria of nephrotic syndrome (NS). We attempted to remove pathogenic T cells through lymphocytapheresis (LCAP) in 6 patients with primary NS, 2 patients with minimal change nephrotic syndrome (MCNS), 2 patients with focal segmental glomerulosclerosis (FSGS), 1 patient with membranous nephropathy (MN), and 1 patient with MN and FSGS using Cellsorba (Asahi Medical Co., Osaka, Japan). LCAP was performed 2 times in 2 consecutive weeks and was followed with corticosteroid therapy with or without cyclosporine A in 5 patients. Two patients with MCNS, 1 with FSGS, and 1 with MN and FSGS showed a dramatic decrease of proteinuria (-30% and -94%) in their urine protein/creatinine ratio. Three out of 4 patients had a complete or partial remission (proteinuria <1g/day) within 8 weeks following immunosuppressive therapy. During the LCAP, T cells, especially activated T cells, decreased significantly in the response group. The other 2 patients, 1 with FSGS and 1 with MN, however, had no response to LCAP and following immunosuppressive therapy or low-density lipoprotein apheresis and suffered from end-stage renal failure or death by pneumonia. These results suggested that LCAP might have a beneficial effect on the treatment of NS, especially MCNS and in some patients with FSGS, despite varying responses to LCAP and concomitant immunosuppressive therapy.     

A novel knock-in prostate cancer model demonstrates biology similar to that of human prostate cancer and suitable for preclinical studies.

Preclinical studies of prostate cancer (CaP) have employed a genetically engineered mouse model, since there is no naturally occurring CaP in rodents. We have previously reported a new knock-in mouse adenocarcinoma prostate (KIMAP) model. In this study, we demonstrate that the new model possesses a tumor architecture of heterogeneity and multifocality similar to that of human CaP, by utilizing a new compound scoring system to compare with the PSP94 (approved gene symbol Msmb) gene-directed transgenic mouse CaP model (TGMAP). KIMAP mice showed a balanced distribution of tumor extent, which penetrated the prostate gland. Comparative studies on cDNA microarrays demonstrated that KIMAP tumors were upregulated with higher contents of immunoresponse genes, whereas PSP-TGMAP tumors had neuroendocrine (NE) differentiation. The majority of KIMAP mice did not progress to NE CaP, which was observed only at a very late stage and a low frequency. Several tumor marker genes characteristic of human CaP were uniquely identified in KIMAP tumors, including hepsin, maspin, Nkx3.1, CD10 and PSP94 (similar to PSA), etc. The differences between these two CaP models are attributed to the introduction of a single endogenous knock-in mutation. Due to the similarities between human CaP tumors and the PSP-KIMAP tumors, this preclinical model may supplement the current transgenic models to study CaP more accurately.