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Polyunsaturated free fatty acids (PUFAs) are known to play critical roles for the development, maintenance, and function of the brain. Recently, we reported that G-protein coupled receptor 40 (GPR40), one type of PUFA receptors, is expressed throughout the adult primate central nervous system including the hippocampus. This opens a possibility that PUFA might act as extracellular signaling molecules at the GPR40 receptor to regulate neuronal function. Here we studied protein expression of GPR40 in the neurogenic niche of the adult monkey hippocampus under normal and postischemic conditions. Confocal laser microscope analysis of immunostained sections revealed GPR40 immunoreactivity in neural progenitors, immature neurons, astrocytes and endothelial cells of the subgranular zone (SGZ) of the dentate gyrus (DG); a well-known neurogenic niche within the adult brain. Immunoblotting analysis showed that the GPR40 protein increased significantly in the second week after global cerebral ischemia as compared with the control. This was compatible with the postischemic increment of GPR40-positive cells in the SGZ as detected by immunofluorescence imaging. Taken together with our previous findings of the SGZ progenitor cell upregulation after ischemia, the present data suggest that PUFA such as docosahexaenoic acid may act via GPR40 to regulate adult hippocampal neurogenesis in primates.

Genetic differences between 36 Pholiota aurivella wild isolates collected from 13 decayed logs of Salicaceae trees distributed along about 1200 m of a streambed in a forest were characterized by somatic incompatibility and mating tests, and by restriction fragment length polymorphism (RFLP) analysis of mitochondrial DNA (mtDNA). There was a perfect correlation between somatic incompatibility and mating type groups, and isolates could be divided into 15 genets (genetically identical clones). Because the mtDNAs of the 36 wild isolates have 14 different EcoRI RFLP patterns, they likely originated from at least 14 distinct wild strains, indicating that multiple wild strains with distinct genetic compositions coexist in the forest investigated in this study. mtDNA variation of P. aurivella is apparently very high despite the close proximity of sample collection sites within the forest. The territories of single P. aurivella genets within a host log are apparently larger than other nonpathogenic wood-decaying basidiomycetes reported previously, such as Flammulina velutipes and Lentinula edodes.

The G-protein coupled receptor 40 (GRP40) is a transmembrane receptor for free fatty acids, and is known for its relation to insulin secretion in the pancreas. Recent studies demonstrated that spatial memory and hippocampal long-term potentiation of rodents and cognitive function of humans are improved by a dietary supplementation with arachidonic and/or docosahexaenoic acids, which are possible ligands for GPR40. While free fatty acid effects on the brain might be related to GPR40 activation, the role of GPR40 in the central nervous system (CNS) is at present not known. Here, we studied expression and distribution of GPR40 in CNS of adult monkeys by immunoblotting and immunohistochemistry. Immunoblotting analysis showed a band of approximately 31 kDa consistent with the size of GPR40 protein. GPR40 immunoreactivity of was observed in the nuclei and/or perikarya of a wide variety of neurons including neurons in the cerebral cortex, hippocampus, amygdala, hypothalamus, cerebellum, spinal cord. In addition, astrocytes of the cerebral white matter, the molecular layer and multiform layer of the cerebral cortex, the subventricular zone along the anterior horn of the lateral ventricle, and the subgranular zone of the hippocampal dentate gyrus showed GPR40 immunoreactivity. The present data first provide a morphological basis for clarifying the role of GPR40 in the primate CNS.

The purpose of this study was to assess the usefulness of curved multiplanar reformatted (MPR) images obtained by multislice CT for the depiction of the main pancreatic duct (MPD) and detection of resectable pancreatic ductal adenocarcinoma. This study included 28 patients with pancreatic carcinoma (size range 12-40 mm) and 22 without. Curved MPR images with 0.5-mm continuous slices were generated along the long axis of the pancreas from pancreatic-phase images with a 0.5- or 1-mm slice thickness. Seven blinded readers independently interpreted three sets of images (axial images, curved MPR images, and both axial and curved MPR images) in scrolling mode. The depiction of the MPD and the diagnostic performance for the detection of carcinoma were statistically compared among these images. MPR images were significantly superior to axial images in depicting the MPD, and the use of both axial and MPR images resulted in further significant improvements. For the detection of carcinoma, MPR images were equivalent to axial images, and the diagnostic performance was significantly improved by the use of both axial and MPR images. High-resolution curved MPR images can improve the depiction of the MPD and the diagnostic performance for the detection of carcinoma compared with axial images alone.

Genetic differences among 18 Lentinula edodes strains isolated from a fallen trunk of Quercus mongolica var. grosseserrata were characterized by mating tests and restriction fragment length polymorphism (RFLP) analyses of mitochondrial DNA (mtDNA). These strains could be divided into six genets of different mating types. Because the mtDNA of the 18 strains showed four different RFLP genotypes, these strains seemed to have originated from at least 4 distinct parental strains. Strains belonging to the same genet were collected from fruiting bodies located not more than about 1 m apart on the fallen tree. Implications of these findings regarding the degree of genetic variation and territory sizes of individual genets of wood-decaying basidiomycetes such as L. edodes are discussed.

To clarify the involvement of fatty acid binding proteins (FABPs) in cerebellar development and function, we explored the distribution of three brain-expressed FABPs, FABP 3, 5 and 7, by comparing three animal groups--infantile, normal and postischemic adult monkeys. Immunoblotting analysis revealed intense expression of FABP 3 and 7, but not of FABP5, in the control and postischemic adult cerebellum. The protein levels of FABP7, but not of FABP 3 or 5, gradually increased until 2 weeks after the insult. Immunohistochemical analysis showed that cerebellar FABP3-positive cells were Purkinje cells and Bergmann glia. FABP5-positive cells were found only in the postischemic cerebellum, and were identified as activated microglia. Interestingly, in the infantile cerebellum, both the granule cell progenitors in the external granular layer (EGL) and the oligodendrocyte progenitors in the internal granular layer (IGL) expressed FABP5. In the adult cerebellum, FABP7 was expressed in Purkinje cells and basket interneurons, while in the infantile cerebellum it was also found in Bergmann glia. These results showed differential expression of FABPs in cerebellar neuronal and glial cell types; FABP 3 and 7 were predominantly expressed in normal cerebellum, FABP5 after ischemic injury, while FABP 3, 5 and 7 were expressed during cerebellar development.

This study aimed at an analysis of expression of epidermal-type and brain-type fatty acid-binding proteins (E-FABP and B-FABP, also called FABP5 and FABP7, respectively) in adult hippocampus and their potential value as neuroprotective factors after ischemic brain damage in monkey model. The immunostaining and Western blotting results show that FABP5 was mainly expressed in neurons, whereas FABP7 was primarily expressed in astrocytes and progenitors of the subgranular zone (SGZ). Interestingly, FABP5 expression in neurons increased in cornu Ammonis 1 (CA1) and remains stable within dentate gyrus (DG) after ischemia; FABP7 expression increased within both CA1 and SGZ. This indicates a potential role for FABP5 and FABP7 in intracellular fatty acid transport within different neural cells. The change in FABP5-7 expression within CA1 and DG of the adult postischemic hippocampus was compatible with previous findings of downregulation in CA1 neurons and upregulation in SGZ progenitor cells after ischemia. Altogether, the present data suggest that polyunsaturated fatty acids, such as docosahexaenoic acid, may act via FABP5 or 7 to regulate adult postischemic hippocampal neuronal antiapoptosis or neurogenesis in primates.

Matrix metalloproteinases (MMPs), zinc-dependent endopeptidases capable of remodeling extracellular matrix and regulating cellular signals, have been implicated in various neurological functions and diseases. However, the role of MMPs in the adult neurogenesis still remains to be clarified, particularly in the primate. Here, we studied differential expression of MMP9/2 in the neurogenic niche of the hippocampal dentate gyrus (DG) after transient global brain ischemia in young adult macaque monkeys. Zymography demonstrated biphasic upregulation of MMP9 in acute (Days 1–3) and delayed (Days 7–15) phases of postischemic reaction, whereas the level of MMP2 was elevated only in the delayed phase. Immunofluorescence histochemistry showed that MMP9 and MMP2 colabeled with markers of endothelial cells, astrocytes, and newborn neurons in the subgranular zone (SGZ) of the DG, and also that the percentage of coexpression significantly increased in the delayed postischemic phase, as compared with controls. However, colabeling with different cell selective markers reached its peak at different time points, i.e., with endothelial cells on Day 7, whereas with astrocytes and newborn neurons on Day 15, respectively. MMPs were localized both in the perikarya and dendrites in the newborn neurons. In conclusion, MMP9/2 expression was regulated in a cell- and time-specific manner in hippocampal neurogenic niche of adult primates. © 2008 Wiley-Liss, Inc.

Transient global cerebral ischemia elicits a nearly total neuronal cell death in the hippocampal CA1 sector, accompanied by a marked microglial and astroglial proliferation. The molecular mechanisms regulating the postischemic glial reaction in the primate brain remain obscure. Here we present in situ evidence that proliferating postischemic microglia in adult monkey CA1 sector express the neurotrophin receptor TrkA, while activated astrocytes were labeled for the TrkA ligand nerve growth factor (NGF) and the tyrosine kinase TrkB, a receptor for brain-derived neurotrophic factor (BDNF). These results implicate NGF and BDNF as regulators of postischemic glial proliferation in adult primate hippocampus.

Definitive erythropoiesis usually occurs in the bone marrow or fetal liver, where erythroblasts are associated with a central macrophage in anatomical units called 'blood islands'. Late in erythropoiesis, nuclei are expelled from the erythroid precursor cells and engulfed by the macrophages in the blood island. Here we show that the nuclei are engulfed by macrophages only after they are disconnected from reticulocytes, and that phosphatidylserine, which is often used as an 'eat me' signal for apoptotic cells, is also used for the engulfment of nuclei expelled from erythroblasts. We investigated the mechanism behind the enucleation and engulfment processes by isolating late-stage erythroblasts from the spleens of phlebotomized mice. When these erythroblasts were cultured, the nuclei protruded spontaneously from the erythroblasts. A weak physical force could disconnect the nuclei from the reticulocytes. The released nuclei contained an undetectable level of ATP, and quickly exposed phosphatidylserine on their surface. Fetal liver macrophages efficiently engulfed the nuclei; masking the phosphatidylserine on the nuclei with the dominant-negative form of milk-fat-globule EGF8 (MFG-E8) prevented this engulfment.

Hepatocytes were isolated from rats fed a diet with or without 0.25% clofibrate, and NAD+ synthesis by the hepatocytes was determined using either [carboxyl-14C]nicotinic acid or [5-3H]tryptophan. NAD+ and total pyridine nucleotides synthesized from [14C]nicotinic acid by the clofibrate-treated cells were not significantly different from those synthesized by the control cells when expressed on the basis of nanomoles per hour per milligram of DNA. On the contrary, NAD+ synthesized from [3H]tryptophan was significantly higher in the clofibrate-treated cells (158% of the control cells) on the basis of nanomoles per hour per milligram of DNA. Clofibrate was inhibitory to tryptophan metabolism as a whole, affecting the glutarate pathway more (decreased to 37% of control) than the kynureninase flux (decreased to 64% of control). As a result, the quinolinate-NAD flux, estimated as the difference in the amounts of tryptophan metabolized by the two metabolic pathways, increased in the clofibrate-treated hepatocytes. The increase in quinolinate during the incubation was 8 times more in the clofibrate-treated cells than in the control cells, which confirmed alteration in the metabolic fluxes of tryptophan in the clofibrate-treated cells. Hepatic quinolinate phosphoribosyltransferase (EC 2.4.2.19) activity increased with dietary clofibrate and returned to the control level 1 week after removing clofibrate from the diet. Nicotinate phosphoribosyltransferase (EC 2.4.2.11) and NAD+ glycohydrolase (EC 3.2.2.5) activities remained unchanged with dietary clofibrate.

We studied the effects of KT1-32 (sodium guaiazulene 3-sulfonate) on development of various acute gastric lesions and duodenal ulcers induced in rats. Male Donryu or Sprague-Dawley rats (220-270 g), fasted (but allowed free access to water) for 24 or 48 hr before the experiments, were used. KT1-32 (dissolved in distilled water, 10-100 mg/kg), given p.o. or intraduodenally (i.d.), dose-dependently inhibited the development of gastric lesions induced by HCl X ethanol (60% ethanol in 150 mM HCl), HCl X aspirin (aspirin 100 mg/kg in 150 mM HCl) or aspirin (150 mg/kg in pylorus-ligated preparation) and Shay ulcers (14 hr pylorus ligation). KT1-32 (30 and 100 mg/kg), given p.o. twice (9.5 hr apart), significantly inhibited the development of duodenal ulcers induced by mepirizole (200 mg/kg, s.c.), but did not inhibit gastric lesions developed simultaneously. KT1-32 (30 and 100 mg/kg), given p.o. or i.d., significantly reduced gastric acid secretion when examined using pylorus ligation preparations. KT1-32 (100 mg/kg, i.d.) had no effect on basal and suppressed duodenal HCO3- secretion by mepirizole. These results suggest that KT1-32 is a promising drug for the treatment of gastritis and peptic ulcers.