Evaluation of the implant type tissue-engineered cartilage by scanning acoustic microscopy

The tissue-engineered cartilages after implantation were nonuniform tissues which were mingling with biodegradable polymers, regeneration cartilage and others. It is a hard task to evaluate the biodegradation of polymers or the maturation of regenerated tissues in the transplants by the conventional examination. Otherwise, scanning acoustic microscopy (SAM) system specially developed to measure the tissue acoustic properties at a microscopic level. In this study, we examined acoustic properties of the tissue-engineered cartilage using SAM, and discuss the usefulness of this devise in the field of tissue engineering. We administered chondrocytes/atelocollagen mixture into the scaffolds of various polymers, and transplanted the constructs in the subcutaneous areas of nude mice for 2 months. We harvested them and examined the sound speed and the attenuation in the section of each construct by the SAM. As the results, images mapping the sound speed exhibited homogenous patterns mainly colored in blue, in all the tissue-engineered cartilage constructs. Contrarily, the images of the attenuation by SAM showed the variation of color ranged between blue and red. The low attenuation area colored in red, which meant hard materials, were corresponding to the polymer remnant in the toluidine blue images. The localizations of blue were almost similar with the metachromatic areas in the histology. In conclusion, the SAM is regarded as a useful tool to provide the information on acoustic properties and their localizations in the transplants that consist of heterogeneous tissues with various components.     

Assembly study for JT-60SA tokamak

The assembly scenarios and assembly tools of the major tokamak components for JT-60SA are studied in the following. (1) The assembly frame (with a dedicated 30-tonne crane), which is located around the JT-60SA tokamak, is adopted for effective assembly works in the torus hall and the temporary support of the components during assembly. (2) Metrology for precise positioning of the components is also studied by defining the metrology points on the components. (3) The sector segmentation for weld joints and positioning of the vacuum vessel (VV), the assembly scenario and tools for VV thermal shield (TS), the connection of the outer intercoil structure (OIS) and the installation of the final toroidal field coil (TFC) are studied, as typical examples of the assembly scenarios and tools for JT-60SA.     

A novel six-phase inverter system with 60-step output voltages forhigh-power motor drives

A novel six-phase voltage-fed inverter system is proposed. The system consists of two main three-phase inverters, coupling reactors, and an additional single-phase inverter. The ripple voltage injected into the DC link by the additional inverter results in 60-step load voltages with the help of the coupling reactors. The main inverters operate at the same frequency as the output, and the additional inverter operates at a frequency six times higher. The advantages and disadvantages of the system are quantitatively discussed     

Cell cycle regulation and differentiation in the human podocyte lineage

Mature podocytes are regarded as growth-arrested cells with characteristic phenotypic features that underlie their function. To determine the relationship between cell cycle regulation and differentiation, the spatiotemporal expression of cyclin A, cyclin B1, cyclin D1, the cyclin-dependent kinase inhibitors (CKIs) p27 and p57, and markers of differentiating podocytes in developing human kidneys was investigated by immunohistochemistry. In S-shaped body stage, Ki-67, a cell proliferation marker that labels the G1/S/G2/M phase, was expressed in the majority (more than 80%) of presumptive podocytes, along with cyclin A (approximately 20% of the Ki-67-positive cells) and cyclin B1 (less than 5% of Ki-67-positive cells) expression. Among these cells), cyclin D1 and CKIs were markedly down-regulated. At the capillary-loop stage, by contrast, CKIs and cyclin D1 were intensely positive in podocytes, whereas no Ki-67, cyclin B1, or cyclin A expression was seen. Moreover, double-immunolabeling and serial-section analysis provided evidence that CKIs and markers specific for differentiating podocytes, namely PHM-5 (podocalyxin-like protein in humans), synaptopodin (a foot process-related protein), and C3b receptor, were co-expressed at the capillary-loop stage. Podocytes were the only cells within the glomeruli that expressed CKIs at immunohistochemically detectable levels. Furthermore, bcl-2 (an apoptosis inhibitory protein) showed a reciprocal expression pattern to that of CKI. These results suggest that 1) the cell cycle of podocytes is regulated by cyclin and CKIs, 2) CKIs may act to arrest the cell cycle in podocytes at the capillary-loop stage, and 3) the specific cell cycle system in podocytes may be closely correlated with their terminal differentiation in humans.     

Analysis of the electronic absorption spectrum of adsorbed layers of methylene blue

Electronic absorption spectra of methylene blue layers adsorbed on glass plates have been measured. Higher aggregates of this dye, up to the tetramer, are shown to exist by an analysis of the aggregate spectra on the basis of a three-dimensional PPP calculation and a diagrammatic exciton-splitting model. A shoulder, located around the monomer peak, observed in the spectrum of the adsorbed methylene blue layer is tentatively assigned to the tetramer. The observed spectral behaviour on aggregation is reproduced by the PPP calculation in which a sandwich type structure is assumed for the aggregates. The band splitting patterns in the methylene blue aggregates are explained diagrammatically in terms of the interactions of the transition moments of the monomer sub-units in an aggregate.     

Ultrasonographic evaluation of the bursae in patients with dialysis-related amyloidosis

Three enumeration methods for Escherichia coli in foods, the Health Protection Branch most-probable-number (MPN) method MFHPB-19, a hydrophobic grid membrane filter method MFHPB-26 (HGMF-indole), and a hydrophobic grid membrane filter method utilizing 5-bromo-4-chloro-3-indolyl-beta-D-glucuronide in a (modified) mFC agar (HGMF-FC-BCIG) were compared in 80 food samples that included naturally and artificially contaminated raw vegetables, mung bean and alfalfa sprouts, raw meats, and chicken carcass rinses. The number of samples confirmed as positive for E. coli were 44, 36, and 42 for the MPN, HGMF-indole, and HGMF-BCIG methods, respectively. By the MPN method, E. coli was detected in 3 samples at levels below the limits of detection of the HGMFs; but the MPN method was very time-consuming. With the HGMF-indole procedure E. coli was missed in 4 artificially contaminated samples. With the HGMF-FC-BCIG method E. coli was enumerated in 1 sample of bean sprouts missed by both the MPN and HGMF-indole procedures. High levels of indole-positive Klebsiella spp. in bean sprouts interfered with the HGMF-indole method, but the blue colonies of E. coli were easily observed in the HGMF-FC-BCIG method. Specificity of the HGMF-FC-BCIG method is high enough that routine confirmation should be unnecessary; however, confirmation of presumptive E. coli is easier since no lethal indole-staining step is involved. It appears to be a very simple method for quantifying E. coli in foods or carcass rinses.     

Effect of early pregnancy on maternal regional cerebral blood flow

OBJECTIVE: The purpose of this study was to assess the effect of early pregnancy on maternal regional cerebral blood flow. STUDY DESIGN: We studied 10 pregnant women at 7 to 19 weeks' gestation by the xenon 133 washout technique by means of single-photon emission computed tomography the day before the abortion was induced and then again at a mean of 42.8 days after the abortion. RESULTS: Blood flow in the cerebral hemispheres decreased after the abortion, with a decline of 8.1% (p < 0.001). Each regional decrease was as follows: 7.6% (p < 0.01) in the frontal lobe, 9.1% (p < 0.01) in the temporal lobe, 12.9% (p < 0.001) in the parietal lobe, 9.8% (p < 0.01) in the basal ganglia, and 16.7% (p < 0.001) in the cerebellum. There was no significant difference in blood flow in the occipital lobe before versus after the abortion. CONCLUSION: Maternal regional cerebral blood flow was increased in early pregnancy compared with the nonpregnant state, except in the occipital lobe.     

Ophthalmic tumor formation in Waldenstr?m's macroglobulinemia

Waldenstr?m's macroglobulinemia is a malignant disease of the reticuloendothelial system; ocular complications reported previously have been concerned chiefly with hyperviscosity manifestations. Ophthalmic tumor formation is rare, although not unheard of, in this particular condition. This report describes two rare instances of Waldenstr?m's macroglobulinemia which involved conjunctival and orbital tumors. One patient developed the tumors after a lengthy clinical course; in the other patient, eyelid and orbital tumors were the first symptoms. Careful examination of the external eye, especially the fornix of the conjunctiva, in patients with Waldenstr?m's macroglobulinemia can identify an initial lesion or invasions to other organs.     

Testicular morphological changes in children with acute lymphoblastic leukemia following chemotherapy

Morphological changes in the testis induced by chemotherapy given according to the Tokyo Children's Cancer Study Group (TCCSG) regimens were studied in children with acute lymphoblastic leukemia (ALL). After informed consent, testicular biopsies were performed 14 times in 12 patients at the end of treatment. The testicular morphology in all cases had sustained a degree of damage. The tubular fertility index (TFI), calculated as the percentage of seminiferous tubules containing identifiable spermatogonia, was from 0 to 42.8% (mean 33.4%) below the normal value. Infiltration of leukemic cells was the most significant factor contributing to the decrease in TFI. There were no differences in the TFI among the TCCSG protocols. Formation of sperm was recognized in six cases, whose ages were 7, 8, 9, 10, 15 and 19 years. In two children, testicular biopsy was performed twice. In the second biopsy, TFI was elevated and sperm formation with the maturation of Leydig cells was observed. A number of other pathological changes were observed: modification of spermatogonia, Sertoli cells and inclusion bodies in spermatogonia, abnormal maturation of Leydig cells, evidence of interstitial fibrosis and thickening of the basement membrane. These results suggest that recent strong chemotherapy for the treatment of ALL might cause severe but not fatal damage to children's testicular tissue. As chemotherapy escalates, more investigation of testicular function will be necessary.