[Successful cyclosporine therapy for a young patient with refractory anemia, myelodysplastic syndrome].
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Publications and source records attributed to M Nitta.
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Checkpoint mechanism plays a crucial role in ensuring genomic integrity during cell cycle. Loss of checkpoint function is known to induce genomic instability and to alter ploidy of dividing cells. In this study, we examined mechanisms of hyperploid formation in glioma cells by treatment with nocodazole, which activates spindle assembly checkpoint by inhibiting microtubule polymerization. By prolonged nocodazole treatment, U251MG human glioma cell, which has a p53 mutation, underwent transient arrest at mitosis, and subsequently exited from mitotic arrest (termed 'mitotic slippage') followed by DNA replication without cytokinesis, resulting in hyperploid formation. Additionally, the heterogeneity in the number of centrosomes per cell increased during the hyperploid formation, suggesting that these hyperploid cells have genomic instability. By employing LN382 glioma cell that has a temperature-sensitive p53 mutation, we found that the activation of p53 prevents hyperploid formation after the prolonged nocodazole treatment. Furthermore, staurosporine, an inhibitor for a broad range of serine/threonine kinases including cdc2, was found to enhance hyperploid formation in U251MG cells by accelerating the induction of mitotic slippage. Interestingly, inhibitors specific for cdc2 kinase prevented the G2 to M transition but did not accelerate mitotic slippage, suggesting that staurosporine-sensitive kinases other than cdc2 are required for maintenance of spindle assembly checkpoint. Moreover, the enhancement of hyperploid formation by staurosporine was also blocked by p53-dependent G1 checkpoint. These results suggest that abrogation of G1 checkpoint is a critical factor for formation of hyperploid cells after the mitotic slippage.
OBJECTIVES: Epithelial ovarian cancers are considered to arise from neoplastic transformation of the ovarian surface epithelium (OSE). However, the earliest events in ovarian carcinogenesis have not been clearly defined because patients are often diagnosed in the advanced stages and useful in vivo and in vitro experimental systems using human OSE cells are lacking. We aimed to improve the availability of experimental models for the study of human ovarian carcinogenesis. METHODS: Subcultured human OSE cells were transfected with SV40 large T antigen. Resulting OSE cell lines were characterized using immunocytochemistry and tested tumorigenicity. RESULTS: Six immortalized OSE cell lines were obtained. All cell lines essentially retained the original morphological features of normal OSE cells and showed higher proliferation rates and saturation density. Although they were all nontumorigenic in athymic mice, OSE2b-2 sv cells, which were selected in soft agar from colonies of an SV40 large T antigen-expressing transfectant, OSE2b sv, produced tumors on the peritoneal surface, mesothelium, and diaphragm and induced ascites after being injected intraperitoneally. Solid tumors also grew when mice were inoculated subcutaneously. The tumor cells were formed in a solid sheet arrangement and no evidence of glandular or squamous differentiation was present. They were weakly immunostained with an antibody against cytokeratin, and intercellular junctions resembling attachment devices were ultrastructurally present between cells. The tumors were histologically diagnosed as undifferentiated carcinomas. CONCLUSIONS: The established cell lines may provide a model system to investigate the mechanisms of cytogenic and molecular changes from normal OSE cells through the various steps of transformation.
Gaucher disease is a genetic lipid storage disease and represents a potentially serious health problem. It arises from a deficiency of glucocerebrosidase activity with secondary accumulation of large quantities of glucocerebroside. Symptoms are usually multisystemic, often debilitating or disabling, and sometimes disfiguring, and they can lead to death. We report objective clinical response's to repeated infusion of human placental and recombinant glucocerebrosidase in 2 patients with type 1 Gaucher disease and increased hemoglobin levels and platelet counts. Splenic volume decreased during the period of enzyme administration. Enzyme replacement therapy has improved the treatment of type 1 Gaucher disease by safely and effectively arresting, decreasing, or normalizing many of its major signs and symptoms. Consideration by physicians must be given to Gaucher disease, and appropriate treatments must be given when confronted with cryptogenic pancytopenia or hepatosplenomegaly.
We conducted a retrospective study of patients with IgG or IgA myeloma who attained plateau to evaluate the relationships between survival and posttreatment nadir M-protein levels and between survival and the response to treatment evaluated by the percent reduction in M-protein. Of the 127 patients comprising 92 IgG and 35 IgA myeloma patients with disease stages II or III, 51 (40.2%) attained plateau. For IgG myeloma patients who attained plateau, survival time was not affected by the percent reduction in M-protein (median survival, 59.5 months for responding patients versus 54.4 months for nonresponding patients, P = .6910). Posttreatment nadir M-protein level, however, did affect survival time (median survival, 61.2 months for <3000 mg/dL versus 25.7 months for >3000 mg/dL, P = .0439). These findings suggest that the posttreatment nadir M-protein level is a stronger discriminator of survival following plateau attainment than the percent reduction of M-protein in patients with IgG myeloma.
In the homing process of hematopoietic progenitor cells (HPCs) to bone marrow, several adhesion molecules play important roles. However, HPCs are subjected to dramatic alteration of freeze-thawing that could affect these molecules. In this study, we investigated the effect of cryopreservation on the expression of adhesion molecules on HPCs. The expression of different adhesion molecules on CD34+ cells was examined by flow cytometry using an immunofluorescence technique. Changes in expression before and after cryopreservation, and that of L-selectin on addition of dimethylsulfoxide (DMSO) or with serum incubation, were investigated. The relationship between expression and function was also determined using a transmigration assay system. L-selectin expression on CD34+ cells derived from mobilized peripheral blood (MPB), bone marrow (BM), and umbilical cord blood (CB) was significantly decreased from 37% to 23%, 48% to 11%, and 67% to 19%, respectively, by the freeze-thawing process, while the expression of other adhesion molecules was not appreciably changed. Within 30 minutes of incubation with DMSO, L-selectin expression on CD34(+) cells significantly decreased from 65% to 22%. Furthermore, this was completely prevented by the matrix metalloproteinase (MMP) inhibitor, KB-R8301, indicating that the loss of L-selectin was due to shedding mediated by an MMP. To determine if L-selectin expression can be upregulated after cryopreservation, thawed samples were cultured overnight with serum. Values were observed to return to or rise higher than those of the fresh samples, this being particularly rapid and pronounced when the CD34+ cells were cocultured with the human BM stromal cell line, HS-27A. Therefore, this adhesion molecule could possibly be restored in vivo after transplantation in a way similar to the in vitro case. Despite considerable damage to HPCs during cryopreservation, changes in these cells are reversible, in line with successful restoration of hematopoiesis after transplantation.
BACKGROUND AND AIMS: E-cadherin, which is a [Ca2+]-dependent, homotypic cell-cell adhesion molecule, is expressed in gastrointestinal epithelial cells. Much has been learned about the down-regulation of E-cadherin expression in gastrointestinal tumours, Barrett's oesophageal dysplasia, and Crohn's disease, but the functions of this molecule in normal gastrointestinal mucosa are less known. METHODS: In this study, we investigated the relationship between E-cadherin expression and permeability using rat cultured gastric and intestinal epithelial cells following a 30-min exposure to various pH solutions. We also investigated the participation of [Ca2+] in these events. RESULTS: E-cadherin expression increased under acid (pH 4) but not alkali (pH 10 or 11) exposure only for gastric epithelial cells. Gastric epithelial permeability was maintained only against acid exposure while intestinal permeability increased under both conditions. Transient influx of [Ca2+] was only observed for gastric epithelial cells just after acid exposure. CONCLUSIONS: These findings suggest that E-cadherin expression on gastric epithelium stabilizes the epithelial barrier against acid, probably through influx of [Ca2+]. This event is thought to be one of the protective mechanisms in gastric mucosa against acid back-diffusion, which is one of the causes of peptic ulcer formation.
Chromosome 14q +, which represents a chromosomal rearrangement involving the immunoglobulin heavy chain gene (IgH) locus, is a genetic hallmark of human multiple myeloma (MM). Here, we report the identification of (14;20)(q32;q11) chromosomal translocations found in MM cells. Double color fluorescence in situ hybridization analyses pinpointed the breakpoints at the 20q11 locus in two MM cell lines within a length of at most 680 kb between the KIAA0823 and MAFB gene loci. Among the transcribed sequences in the vicinity of the breakpoints, an ectopic expression of the MAFB gene, which is located at 450 - 680 kb telomeric to one of the breakpoints and encodes a member of the MAF family basic region / leucine zipper transcription factor, was demonstrated to be associated with t(14;20). This finding, together with that of a previous study describing its transforming activity, suggests that the MAFB gene may be one of the targets deregulated by regulatory elements of the IgH gene as a result of t(14;20).
In order to investigate the mucosal injury mechanism in UC, we made dextran sulfate sodium (DSS)-induced colitis in rat and examined pathological findings, MPO activity, PGE(2) level, and local mRNA expression and secretion of IL-1 beta, TNF-alpha, GRO/CINC-1 and IL-10 in DSS colitis mucosa. Moreover, we estimated the correlation between the severity of mucosal damage and changes of these local inflammatory mediators' values. Neutrophil infiltration was marked and MPO activity was locally increased in proportion to the severity of mucosal damage. The mRNA expression and secretion of IL-1 beta, GRO/CINC-1 and IL-10 were increased. Especially, the secretions of IL-1 beta and GRO/CINC-1 were increased in proportion to the severity of mucosal damage. However, those of TNF-alpha were not increased in the colitis mucosa. An abnormal macrophage function and the presence of macrophage subtypes producing different cytokines would be predicted from our TNF-alpha data. The lesion was less severe in the colonic mucosa with higher levels of endogenous PGE(2), while it was more severe in the colonic mucosa with lower levels of endogenous PGE(2), implicating this compound as an inhibitory factor against the development of inflammation in the affected mucosa. Our results suggest that PGE(2) might have therapeutic applicability to UC.
A 57-year-old woman was hospitalized with malignant lymphoma of the right talus. After treatment, complete remission was obtained. Gallium-67 scintigraphy to confirm the remission demonstrated increased uptake in the whole body skeletal muscle, especially in her thighs. Biopsy of right gastrocnemius muscle showed epithelioid granuloma. Serum angiotensin-converting enzyme activity (ACE) and lysozyme had increased to several times the normal range. We diagnosed her disease as bone-associated sarcoidosis-lymphoma syndrome. Human herpes virus 8 (HHV-8) genome was examined in the bone marrow specimen, and the relationship between sarcoidosis-lymphoma syndrome and HHV-8 was discussed.
The xeroderma pigmentosum group A protein (XPA) plays a central role in nucleotide excision repair (NER). To identify proteins that bind to XPA, we screened a HeLa cDNA library using the yeast two-hybrid system. Here we report a novel cytoplasmic GTP-binding protein, designated XPA binding protein 1 (XAB1). The deduced amino acid sequence of XAB1 consisted of 374 residues with a molecular weight of 41 kDa and an isoelectric point of 4.65. Sequence analysis revealed that XAB1 has four sequence motifs G1-G4 of the GTP-binding protein family in the N-terminal half. XAB1 also contains an acidic region in the C-terminal portion. Northern blot analysis showed that XAB1 mRNA is expressed ubiquitously, and immunofluorescence analysis revealed that XAB1 is localized mainly in the cytoplasm. Consistent with the GTP-binding motif, purified recombinant XAB1 protein has intrinsic GTPase activity. Using the yeast two-hybrid system, we elucidated that XAB1 binds to the N-terminal region of XPA. The deletion of five amino acids, residues 30-34 of XPA, required for nuclear localization of XPA abolished the interaction with XAB1. These results suggest that XAB1 is a novel cytoplasmic GTPase involved in nuclear localization of XPA.
We previously reported that intracolonic administration of enprostil, a prostaglandin-E(2) (PGE(2)) analogue, had therapeutic effects on acute colitis induced in rodents by dextran sulfate sodium (DSS). In addition, production of growth-regulated gene product/cytokine-induced neutrophil chemoattractant-1 [GRO/CINC-1; an interleukin(IL)-8 like cytokine] was suppressed in the inflamed tissues. In the present study we used a human colon cancer cell line (HT-29) to investigate enprostil effects on the IL-8 production of intestinal epithelial cells stimulated by various stimulants. In a MTT assay, concentrations of enprostil >10(-5)M had cytotoxitic effects on HT-29 cells. Furthermore, 10(-6) M enprostil suppressed IL-8 production in HT-29 cells, SW620 and CaCo2 stimulated with interleukin-1 beta (IL-1 beta) or lipopolysaccharide (LPS), but did not suppress this response when cells were stimulated with tumour necrosis factor (TNF)-alpha. These results suggest that enprostil affects a point in the pathway between the IL-1 receptor or LPS receptor and nuclear factor-kappa B(NF-kappa B), without affecting the pathway between the TNF receptor and NF-kappa B, with the latter factor being required for the IL-8 gene transcription. The therapeutic effect of exogenous enprostil on DSS colitis may involve the inhibition of IL-8 production in colonic epithelial cells stimulated by IL-1 beta or LPS.
The width of the hypopharynx and oropharynx before and after the operation correction of glosso-larynx (CGL) was compared by cranial X-ray film. After the operation, the hyoid bone was seen to have moved downward, and the cranial bone was observed to have rotated forward. As a result, the hypopharynx and the oropharynx were expanded. Expansion of the hypopharynx resulted in the decreased resistance of flow decreased and the increased in airflow.
UPPP includes uvulotomy. The uvula works as the pilot for eating and swallowing. We performed an operation which left the uvula intact and opened the pharynx by Z-opening the palate, Z-pharyngoplasty (ZPP). Twenty-four patients were studied before and after ZPP. The results of the operations were satisfactory. No patients complained of symptoms after uvulectomy. As for the changes indicated by sleep monitoring, minimum SaO2 increased significantly (P = 0.0026), pulse rate decreased significantly (P = 0.0144), apnea index decreased significantly (P = 0.0392), snoring decreased (P = 0.064), and the amount of hours of sleep when SaO2 was over 95% increased (P = 0.0690) after ZPP.
We have recently found that the infection with herpes simplex virus type-1 (HSV-1) of primary sensory neurons induces nociceptive hypersensitivity to noxious mechanical (hyperalgesia) and tactile stimulation (allodynia) in mice. In the present experiments, we determined the distribution of HSV-1 in the dorsal root ganglia and examined the effects of four analgesic agents on hyperalgesia and allodynia. HSV-1 was inoculated on the unilateral shin. HSV-antigen-positive cells were detected in the L4 and L5 dorsal root ganglia on days 5 and 7, but not day 3, post-inoculation. About 80% of the positive cells were small in size. Allodynia and hyperalgesia appeared on day 5 post-inoculation. Antinociceptive effects of analgesic agents were examined on day 6 post-inoculation. Morphine (1-5 mg/kg, subcutaneous) and gabapentin (10-100 mg/kg, peroral) dose-dependently inhibited both allodynia and hyperalgesia. Diclofenac (10-100 mg/kg, intraperitoneal) also produced antinociceptive effects, but there was a ceiling for the effect on hyperalgesia. Amitriptyline (3, 10 mg/kg, subcutaneous) did not affect allodynia and hyperalgesia. The results suggest that mechanical allodynia and hyperalgesia appeared when HSV-1 proliferated in the sensory neurons. This mouse model may be useful for studying the mechanisms of acute herpetic pain and anti-neuropathic pain agents.
The shape of the choanal openings were examined in 173 babies aged zero to six months using digital video fiberscope inserted via nose. A numerical analysis and the fluid mechanics were then calculated for each recorded choanal opening. The choanal openings in one month old babies were a flat oval shape. Vertical development was faster than that of horizontal development, and the choanal openings changed from a flat oval to a round and finally a vertical oval shapes as the babies aged from two to four months. Both the air resistance and airflow ratio in the choanae can be calculated by Navier-Stoke's equation, if the choanae are assumed to be an oval tube. Using this equation, it was calculated that the air resistance ratio was one to five and the airflow ratio increased five times from neonates to six month old babies.
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A 29-year-old man was admitted to our hospital with a history of recurrent right upper quadrant abdominal pain and vomiting. These symptoms appeared intermittently for 7 years. Various examinations revealed a diagnosis of midgut malrotation. Laparotomy was performed and revealed reverse rotation of the duodenum with paraduodenal hernia and a normal rotating colon. This case suggests that recurrent abdominal complaints in an adult should arouse suspicion of midgut malrotation.