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Numerical analysis and measurement of glass flow in a small melting furnace
Control of glass flow in a glass tank is a key technology in the glass melting process. The flow and temperature distributions of the glass melt greatly affect the quality of glass products. However, these phenomena have not been well understood due to the difficulty involved in the measurement as a result of the high temperature of the glass melt. Α small melting furnace was developed that was heated by electrodes. The glass flow was measured and analyzed by 3-D computer simulation. The numerical results show good agreement with the experimentally measured values. It is shown that it is possible to control the glass convection using a variety of the electric boosting conditions, the heat loss through walls and the charged glass batch. The quality of glass melt was evaluated by analyzing the temperature histories of virtual particles the furnace was charged with. It is found that the temperature of the particles is high and stable near the throat, as shown by the experimental data
Phenotype Analysis and Quantification of Proliferating Cells in the Cortical Gray Matter of the Adult Rat
In intact adult mammalian brains, there are two neurogenic regions: the subependymal zone and the subgranular layer of the hippocampus. Even outside these regions, small numbers of proliferating precursors do exist. Many studies suggest that the majority of these are oligodendrocyte precursors that express NG2, a chondroitin sulfate proteoglycan, and most of the residual proliferating cells seem to be endothelial cells. However, it is still unclear whether NG2-immunonegative proliferating precursors are present, because previous studies have neglected their possible existence. In this study, we systematically analyzed the phenotypes of the proliferating cells in the intact adult rat cortical gray matter. We improved our techniques and carefully characterized the proliferating cells, because there were several problems with identifying and quantifying the proliferating cells: the detection of NG2-expressing cells was dependent on the fixation condition; there were residual proliferating leukocytes in the blood vessels; and two anti-NG2 antibodies gave rise to different staining patterns. Moreover, we used two methods, BrdU and Ki67 immunostaining, to quantify the proliferating cells. Our results strongly suggest that in the intact adult cerebral cortical gray matter, there were only two types of proliferating cells: the majority were NG2-expressing cells, including pericytes, and the rest were endothelial cells
Differential expression of nuclear lamin subtypes in the neural cells of the adult rat cerebral cortex
Lamins are type V intermediate filament proteins that are located beneath the inner nuclear membrane. In mammalian somatic cells, LMNB1 and LMNB2 encode somatic lamins B1 and B2, respectively, and the LMNA gene is alternatively spliced to generate somatic lamins A and C. Mutations in lamin genes have been linked to many human hereditary diseases, including neurodegenerative disorders. Knowledge about lamins in the nervous system has been accumulated recently, but a precise analysis of lamin subtypes in glial cells has not yet been reported. In this study we investigated the composition of lamin subtypes in neurons, astrocytes, oligodendrocyte-lineage cells, and microglia in the adult rat cerebral cortex using an immunohistochemical staining method. Lamin A was not observed in neurons and glial cells. Lamin C was observed in astrocytes, mature oligodendrocytes and neurons, but not observed in oligodendrocyte progenitor cells. Microglia also did not stain positive for lamin C which differed from macrophages, with lamin C positive. Lamin B1 and B2 were observed in all glial cells and neurons. Lamin B1 was intensely positive in oligodendrocyte progenitor cells compared with other glial cells and neurons. Lamin B2 was weakly positive in all glial cells compared to neurons. Our current study might provide useful information to reveal how the onset mechanisms of human neurodegenerative diseases are associated with mutations in genes for nuclear lamin proteins
Indications for portal vein embolization combined with major hepatic resection for advanced-stage hepatocellular carcinomas. A preliminary clinical study. Dig Surg 2000; 17: 587-594 2 Man K, Fan ST, Ng IO, Lo CM, Liu CL, Wong J. Prospective evaluation of
Abstract Background: Criteria for selection of patients for portal vein embolization (PVE) before major hepatectomy for advanced-stage hepatocellular carcinoma (HCC) have not been clarified in detail. This study was aimed at defining those benefiting from this therapy in a retrospective fashion. Patients and Methods: Firstly, to determine liver functional criteria for applying this approach 26 patients with stage III (17 patients) or IV (9 patients) disease, who underwent major hepatectomies after PVE, were divided into those without major complications (20 patients) and a postoperative liver failure group (6 patients). Clinical, analytical, and hemodynamic parameters obtained before and after PVE were compared between the groups. Secondly, to define the application of this approach with regard to tumor progression survival rates of patients were also obtained, taking into account factors which affect tumor development, i.e. lesion size, intrahepatic metastasis and vascular invasion. Results: With regard to liver function 4 nonindications were obtained: (1) a portal pressure measured right after PVE 125 cm H 2 O; (2) post-PVE serum hyaluronate 1 200 ng/ml; (3) pre-PVE serum cholinesterase ! 150 U/l; (4) post-PVE serum cholinesterase ! 150 U/l. In view of the tumor progression in patients with HCCs featuring intrahepatic metastasis spread to more than 3 segments (IM3) 1-, 3-and 5-year survival rates were low (42.9, 28.6 and 0%) with a statistical significance, compared to those in patients with intrahepatic metastasis limited in the same lobe (76.9, 46.2 and 24.6%). Conclusions: When laboratory data fulfill 3 or more of the criteria, the extent of hepatic resection may have to be carefully reconsidered. Patients with HCCs featuring IM3 intrahepatic metastasis may not benefit from the aggressive approach described here
Sox2 promotes survival of satellite glial cells in vitro
Sox2 is a transcriptional factor expressed in neural stem cells. It is known that Sox2 regulates cell differentiation, proliferation and survival of the neural stem cells. Our previous study showed that Sox2 is expressed in all satellite glial cells of the adult rat dorsal root ganglion. In this study, to examine the role of Sox2 in satellite glial cells, we establish a satellite glial cell-enriched culture system. Our culture method succeeded in harvesting satellite glial cells with the somata of neurons in the dorsal root ganglion. Using this culture system, Sox2 was downregulated by siRNA against Sox2. The knockdown of Sox2 downregulated ErbB2 and ErbB3 mRNA at 2 and 4 days after siRNA treatment. MAPK phosphorylation, downstream of ErbB, was also inhibited by Sox2 knockdown. Because ErbB2 and ErbB3 are receptors that support the survival of glial cells in the peripheral nervous system, apoptotic cells were also counted. TUNEL-positive cells increased at 5 days after siRNA treatment. These results suggest that Sox2 promotes satellite glial cell survival through the MAPK pathway via ErbB receptors
Sox2 in the adult rat sensory nervous system
Sex-determining region Y (SRY)-box 2 (Sox2) is a member of the Sox family transcription factors. In the central nervous system, Sox2 is expressed in neural stem cells from neurogenic regions, and regulates stem cell proliferation and differentiation. In the peripheral nervous system, Sox2 is found only in the immature and dedifferentiated Schwann cells, and is involved in myelination inhibition or N-cadherin redistribution. In the present immunohistochemical study, we found that Sox2 is also expressed in other cells of the adult rat peripheral nervous system. Nuclear Sox2 was observed in all satellite glial cells, non-myelinating Schwann cells, and the majority of terminal Schwann cells that form lamellar corpuscles and longitudinal lanceolate endings. Sox2 was not found in myelinating Schwann cells and terminal Schwann cells of subepidermal free nerve endings. Satellite glial cells exhibit strong Sox2 immunoreactivity, whereas non-myelinating Schwann cells show weak immunoreactivity. RT-PCR confirmed the presence of Sox2 mRNA, indicating that the cells are likely Sox2 expressors. Our findings suggest that the role of Sox2 in the peripheral nervous system may be cell-type-dependent
Increased Histone H3 Phosphorylation in Neurons in Specific Brain Structures after Induction of Status Epilepticus in Mice
Status epilepticus (SE) induces pathological and morphological changes in the brain. Recently, it has become clear that excessive neuronal excitation, stress and drug abuse induce chromatin remodeling in neurons, thereby altering gene expression. Chromatin remodeling is a key mechanism of epigenetic gene regulation. Histone H3 phosphorylation is frequently used as a marker of chromatin remodeling and is closely related to the upregulation of mRNA transcription. In the present study, we analyzed H3 phosphorylation levels in vivo using immunohistochemistry in the brains of mice with pilocarpine-induced SE. A substantial increase in H3 phosphorylation was detected in neurons in specific brain structures. Increased H3 phosphorylation was dependent on neuronal excitation. In particular, a robust upregulation of H3 phosphorylation was detected in the caudate putamen, and there was a gradient of phosphorylated H3+ (PH3+) neurons along the medio-lateral axis. After unilateral ablation of dopaminergic neurons in the substantia nigra by injection of 6-hydroxydopamine, the distribution of PH3+ neurons changed in the caudate putamen. Moreover, our histological analysis suggested that, in addition to the well-known MSK1 (mitogen and stress-activated kinase)/H3 phosphorylation/c-fos pathway, other signaling pathways were also activated. Together, our findings suggest that a number of genes involved in the pathology of epileptogenesis are upregulated in PH3+ brain regions, and that H3 phosphorylation is a suitable indicator of strong neuronal excitation
Differential responses of endogenous adult mouse neural precursors to excess neuronal excitation
Adult neurogenesis in the subgranular zone of the hippocampus (SGZ) is enhanced by excess as well as mild neuronal excitation, such as chemoconvulsant‐induced brief seizures. Because most studies of neurogenesis after seizures have focused on the SGZ, the threshold of neuronal excitation required to enhance neurogenesis in the subventricular zone (SVZ) is not clear. Therefore, we examined the responses of SVZ precursors to brief generalized clonic seizures induced by a single administration of the chemoconvulsant pentylenetetrazole (PTZ). Cell cycle progression of precursors was analysed by systemic administration of thymidine analogues. We found that brief seizures immediately resulted in cell cycle retardation in the SVZ. However, the same effect was not seen in the SGZ. This initial cell cycle retardation in the SVZ was followed by enhanced cell cycle re‐entry after the first round of mitosis, leading to precursor pool expansion, but the cell cycle retardation and expansion of the precursor pool were transient. Cell cycle progression in the PTZ‐treated group returned to normal after one cell cycle. The numbers of precursors in the SVZ and new neurons in the olfactory bulb, which are descendants of SVZ precursors, were not significantly different from those in control mice more than 2 days after seizures. Because similar effects were observed following electroconvulsive seizures, these responses are likely to be general effects of brief seizures. These results suggest that neurogenesis in the SVZ is more tightly regulated and requires stronger stimuli to be modified than that in the SGZ
Treatment for Peritoneal Dissemination from Metastatic Recurrent Colorectal Cancer with Ileus
Bone Metastasis After Curative Resection of Small Intestinal Gastrointestinal Stromal Tumors: Repeat Recurrence with Liver Metastases: Case Report
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