Divergence of natural killer cell receptor and related molecule in the decidua from sporadic miscarriage with normal chromosome karyotype

The aim of this cohort study was to investigate immunophenotypic characteristics of natural killer (NK) cells by assessing specific molecules expressed in the decidua of sporadic miscarriages and induced abortions. The deciduae were obtained from 29 consecutively seen women whose pregnancies ended in first trimester miscarriages (MS), and the fetal chromosome karyotype of these MS was analysed. Additionally, 13 deciduae were obtained from induced abortion (IA) with informed consent. The expression of perforin, CD94, CD161, CD158a, CD158b, CD244 on CD3-CD56+NK cells, and perforin on CD3+CD8+ T cells was analysed by flow cytometry. The CD158a (mean+/-SD, 26.2+/-14.7%) and CD94 (50.2+/-25.7%) expressions in MS with normal chromosome karyotype (MSNK; n=11) were significantly decreased as compared with those (41.5+/-19.5%, 71.4+/-20.4%) in MS with abnormal karyotype (MSAK; n=18) and those (44.3+/-21.9%, 80.8+/-17.5%) in IA (n=13). Conversely, the perforin expression on CD3-CD8-CD56+NK cells (76.3+/-11.0%) and CD3+CD8+T cells (30.6+/-9.2%) in MSNK was significantly increased as compared with those (66.8+/-16.6%, 23.6+/-8.7%) in MSAK and those (62.9+/-11.6%, 19.7+/-8.1%) in IA. A positive correlation between CD94 and CD158a expressions on NK cells, negative correlations between CD94 on NK cells and perforin on NK cells/T cells, and between CD158a on NK cells and perforin on T cells were found in the decidua. A divergence of NK cell repertoire in the decidua might be related to aetiology of sporadic MSNK.     

Anatomical study of meandering and functions of human intralaryngeal artery

In recent years, partial laryngectomy and partial reconstruction are increasingly intended for conservation of functions of phonation and swallowing. In partial reconstruction, it is important to comprehend morphological characteristics of the blood vessels distributed in the larynx, but there have been only few reports discussing detailed information about them. Previous reports on laryngeal blood vessels have shown that branches of some arteries show remarkable "meandering". In the present study, we devised a method for objectively determining the morphological nature, "meandering" and assessed functions of the arteries. Intralaryngeal arteries were excised from the larynx of cadavers prepared for practice in anatomy, and images of the "meandering" artery were analyzed with NIH Image. The extent of "meandering" was expressed mainly as the ratio of the total length of the blood vessel to the distance between the starting point and the end point of meandering. The results showed that there was a significant difference in the extent of meandering between superior posterior and medial posterior branches of superior laryngeal artery. These arteries, which were distributed in the arytenoid region, were found to be of primary importance in partial laryngectomy and partial reconstruction of the larynx.     

Migration of enhanced green fluorescent protein expressing bone marrow-derived microglia/macrophage into the mouse brain following permanent focal ischemia

Brain ischemia induces a marked response of resident microglia and hematopoietic cells including monocytes/macrophages. The present study was designed to assess the distribution of microglia/macrophages in cerebral ischemia using bone marrow chimera mice known to express enhanced green fluorescent protein (EGFP). At 24 h after middle cerebral artery occlusion (MCAO), many round-shaped EGFP-positive cells migrated to the ischemic core and peri-infarct area. At 48-72 h after MCAO, irregular round- or oval-shaped EGFP/ionized calcium-binding adapter molecule 1 (Iba 1)-positive cells increased in the transition zone, while many amoeboid-shaped or large-cell-body EGFP/Iba 1-positive cells were increased in number in the innermost area of ischemia. At 7 days after MCAO, many process-bearing ramified shaped EGFP/Iba 1-positive cells were detected in the transition to the peri-infarct area, while phagocytic cells were distributed in the transition to the core area of the infarction. The distribution of these morphologically variable EGFP/Iba 1-positive cells was similar up to 14 days from MCAO. The present study directly showed the migration and distribution of bone marrow-derived monocytes/macrophages and the relationship between resident microglia and infiltrated hematogenous element in ischemic mouse brain. It is important to study the distribution of intrinsic and extrinsic microglia/macrophage in ischemic brain, since such findings may allow the design of appropriate gene-delivery system using exogenous microglia/macrophages to the ischemic brain area.     

A simplified method for the preparation of EAC14 intermediate cells using human serum treated with methylprednisolone

The inhibitory effect of methylprednisolone 21-succinate ester (MPS) on the activities of complement components in human serum was studied by incubating human serum with various concentrations of MPS at 37 degrees C for 30 min and then measuring the residual activity of each component in human serum. The formation of EAC1 and EAC14 by C1 and C4 respectively, were only weakly inhibited by MPS at a final concentration of 10 mg/ml. In contrast, the same concentration of MPS completely inhibited the capacity of C2, C3, C5 and C6-9 to induce respective succeeding intermediates. On the basis of these findings a simplified method was devised for the preparation of EAC14 intermediates using human serum pretreated with MPS.     

Heterogeneity of primary malignant melanomas in oral mucosa: an analysis of 43 cases in Japan

In contrast to Caucasians, Japanese people have a relatively high incidence of malignant melanoma in the oral cavity and volar-subungual skin. The classification of oral melanoma has not been established. We report 7 new cases of oral melanoma, with a review of 36 cases, published in Japan, between 1970 and 1984. Most of the cases reviewed have radial growth phases, and their gross and microscopic features seem to correspond to those of acral lentiginous melanoma of the skin. However, 1 of our cases and 3 previously reported cases of oral nodular melanoma suggest the presence of melanoma heterogeneity in the oral cavity.     

Evaluation of a new reflectance pulse oximeter for clinical applications

The design of a noninvasive reflectance pulse oximeter that uses the same principle of transmittance pulse oximeter and analyses the oxygen saturation of arterial blood was described. Four sets of red and infra-red LEDs were used as light sources. The respective reflectance photoelectric outputs were used to make an internal calibration curve of the instrument relative to the arterial oxygen saturation values measured with a Co-Oximeter (OSM-3) in five healthy nonsmoking subjects during steady-state hypoxaemia. The accuracy of the present instrument was studied in six patients with respiratory failure. From 22 samples, a good correlation coefficient (0.98) with a standard deviation of 1.42 was obtained in the range between 73 and 100 per cent between the arterial oxygen saturation measured with the present instrument and that with the Co-Oximeter. The result strongly suggests the usefulness of this oximeter in monitoring patients with hypoxaemia.     

Evolution of interleukin-18 binding proteins and interleukin-1 receptor, type II proteins

Interleukin-18 (IL-18) is one of the pivotal cytokines controlling the defense mechanism called inflammation. As a first step to develop proteins for controlling the IL-18 level, we initiated a study of IL-18-binding proteins (IL-18BPs). Twenty-four IL-18BP family members, 11 from vertebrates and 13 from chordopoxviruses, were picked from the NCBI database. Eight of these vertebrate IL-18BPs and two of the chordopoxvirus IL18-BPs were identified here and characterized as new members of the IL-18BP family. Their IL-18 binding domains were aligned and the distribution of highly conserved critical amino acid residues was analyzed and used to construct a phylogenetic tree. From this tree it was inferred that at least two independent events created two different ancestral viral IL-18BP genes by retroposition of IL-18BP genes from the vertebrate lineage. These two events are estimated to have occurred after an ancient mammalian IL-18BP gene diverged from birds, and before the mammalian IL-18BP gene diverged into human, ungulate and rodent IL-18BP genes. Moreover, our results suggest that IL-18BP and interleukin-1 receptor, type II (IL-1R2) had a common ancestral gene and diverged from the ancestral gene into IL-18BP and IL-1R2 genes in the fish period.     

Thin-filament-binding domains of cardiac and fast skeletal muscle troponin I isoforms as studied by epitope tagging

We examined the binding domains of cardiac and fast skeletal muscle troponin I (CTnI and FTnI, respectively) to myofibrils (MFs). Deletion mutants containing CTnI amino acid residues 1–79, 43–207 and 80–207 (CTnI-head, CTnI-tail-1 and CTnI-tail-2, respectively) and FTnI amino acid residues 1–54 and 55–182 (FTnI-head and FTnI-tail, respectively) were transiently expressed in cardiac and fast skeletal muscle cells. To monitor the intracellular localization of these exogenously introduced truncated TnIs, epitope tagging was used. CTnI-tail-1 was incorporated into cardiac MFs specifically, but CTnI-tail-2 was not assembled onto any MFs examined. This suggests that there is no potent actin filament-binding site in CTnI-tail-2. Since CTnI-tail-1 has an amino acid extension (CTnI residues 43–79) whose sequence is longer than that of CTnI-head-2; it appears that this sequence extension is important in binding to cardiac MFs. FTnI-tail, containing the inhibitory domain of actomyosin ATPase, showed intensive and specific incorporation into fast MFs. FTnI-tail was a homologous fragment of CTnI-tail-2, but the binding patterns of these two domains differed greatly from each other. It is possible that the absence of potent binding affinity of CTnI-tail-2 corresponding to the inhibitory domain of actomyosin ATPase is advantageous for continuous cardiac muscle contraction, since a potent inhibitory activity is a serious obstacle to cardiac muscle contraction. It can be assumed that distinctive binding ability of functional domains of TnI-tails reflect unique adaptations to muscles with different physiological properties.     

Human T-cell receptor BV6 gene polymorphism in relation to expression level and CD4/CD8 skewness

Using 50 samples of umbilical cord blood lymphocytes from Japanese donors, we analysed two human T-cell receptor beta variable (TCRBV) genes, BV6S4 and BV6S5, for their polymorphism, usage frequencies and CD4/CD8 skewness. They showed contrasting CD4/CD8 skewness, BV6S4 to CD8+ T cells and BV6S5 to CD4+ T cells. Genotyping of the BV6S4 alleles (A1, A2 and A3) revealed two of the six possible BV6S4 genotypes, A1/A2 and A2/A2. Among the two BV6S4 genotypes, no significant difference was detected in usage frequency or CD4/CD8 skewness. On the other hand, genotyping of the BV6S5 alleles (A1 and A2) revealed all three possible BV6S5 genotypes, A1/A1, A1/A2 and A2/A2, and the gene usage frequency was high, in the order A1/A1 > A1/A2 > A2/A2. These results indicate that the amino acid substitutions in BV6S5 (S36R and G70E) are in some way associated with the expression level of this gene. In the analysis of CD4/CD8 skewness, the three BV6S5 genotypes had similar skewness, indicating that A1 alleles are expressed more frequently than A2 alleles in both CD4+ and CD8+ T-cell populations. Although BV6S5 exhibits marked skewness to CD4+ T cells, our results indicate that the higher expression of A1 alleles is not associated with the increased ratio of CD4+ T cells.