Biomedical subjects

T Fujimoto

Publications and source records attributed to T Fujimoto.

At least 55 records · Page 3Linked to original sources

PubMed2001

Germ-line chimera by lower-part blastoderm transplantation between diploid goldfish and triploid crucian carp.

Germ-line chimerism was successfully induced by blastoderm transplantation from donor triploid crucian carp, which reproduces gynogenetically, to recipient diploid goldfish, which reproduces bisexually. Lower part of donor blastoderm including primordial germ cells (PGCs) was sandwiched between recipient blastoderm at the mid- to late-blastula stage. When donor grafts were prepared from intact embryos or ventralized ones by removing vegetal yolk hemisphere at the 1- to 2-cell stage, malformations including double axes were observed in the resultant chimeras transplanted with grafts from intact embryos at the hatching stage, while a few malformations in those from ventralized embryos. PGCs originated from donor grafts were observed around the gonadal anlage at 10 days post-fertilization in chimeras. When ploidy of erythrocytes and epidermal cells in chimeric fish was examined by flow-cytometry, no triploid cells were detected at 1- and 5-year-old chimeras. Three-year-old chimeric fish (n = 5) laid eggs originated from the donor together with those from the recipient. The frequency of eggs from the donor crucian carp blastoderm varied from 3.1 to 89.3% between chimeras.

Animals↗

PubMed2001

Histopathological prognostic factors of adult granulosa cell tumors of the ovary.

BACKGROUND: The prognostic factors of adult granulosa cell tumor (AGCT) have not been well defined. METHODS: In 27 AGCT patients, we examined clinical stage, microscopic patterns, mitotic index (MI), and lymph-vascular space invasion (LVSI) to determine whether these factors were related to disease-free survival (DFS) of patients with AGCT. We also performed immunohistochemical examination for p53. RESULTS: Seventeen cases represented stage I tumors, four stage II, five stage III, and one stage IV. Patients with stage I disease had more favorable prognosis than those with stage II to IV disease (p=0.034). There was no relation between the microscopic patterns and the DFS. The MI, which was categorized into < or =3/10 high power field (HPF) and > or =4/10 HPF, was significantly related to patients DFS (p<0.0005). The DFS time for patients with moderate or prominent LVSI was significantly shorter than that for patients with no or minimal LVSI (p<0.0001). By multivariate analysis, MI and LVSI were shown to be independent prognostic factors. Five of seven patients with recurrent tumor had extrapelvic spread; two in the abdominal cavity and three in the liver. CONCLUSION: The results of this study suggest that prognosis for patients with AGCT depends on the MI and LVSI. During the follow-up period of patients, they need to be examined for distant metastasis including liver.

Adolescent↗

PubMed2001

Imbalance between interleukin-6 and adrenomedullin mRNA levels in peripheral blood mononuclear cells of patients with lupus nephritis.

In this study, we measured the mRNA levels of adrenomedullin (AM), C-type natriuretic peptide, vascular endothelial growth factor, interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) in peripheral blood mononuclear cells (PBMC) of 34 patients with lupus nephritis (LN) (15 active and 19 inactive) and 30 healthy volunteers. mRNA levels were measured using a real-time quantitative PCR METHOD: Compared with healthy volunteers, IL-6 mRNA levels were elevated in LN patients (P < 0.005), while AM mRNA levels were decreased (P < 0.05). Also, IL-6 mRNA levels were higher and AM mRNA levels lower in active LN patients compared with inactive LN patients. In addition, IL-6 mRNA levels positively correlated and AM mRNA levels negatively correlated with SLE disease activity index and laboratory findings, such as blood urea nitrogen, serum creatinine, 50% haemolytic unit of complement and urinary excretion of protein over 24 h. Furthermore, IL-6 mRNA levels were negatively correlated with AM mRNA levels within the same LN patients. With regard to pathological findings, our results showed that IL-6 mRNA levels were higher, and AM mRNA levels significantly lower in patients with a high activity index compared to those with a low activity index. Following treatment with prednisolone, IL-6 mRNA levels in active LN patients decreased and AM mRNA levels increased to levels comparable to those in inactive LN and healthy volunteers. In vitro studies further demonstrated that elevated IL-6 mRNA levels in active LN patient PBMC were suppressed by the addition of adrenomedullin. Our results suggest that an imbalance between IL-6 and AM levels may play an important role in the progression of SLE, and that the mRNA levels of these genes in PBMC may be used as a disease activity index for SLE.

Adrenomedullin↗

PubMed2001

Requirement of Runx1/AML1/PEBP2alphaB for the generation of haematopoietic cells from endothelial cells.

Recent studies revealing that endothelial cells derived from E8.5-E10.5 mouse embryos give rise to haematopoietic cells appear to correspond to previous histological observations that haematopoietic cell clusters are attached to the ventral aspect of dorsal aorta in such a way as if they were budding from the endothelial cell layer. Gene disruption studies have revealed that Runx1/AML1 is required for definitive haematopoiesis but not for primitive haematopoiesis, but the precise stage of gene function is not yet known. We found that mice deficient in Runx1/AML1 (an alpha subunit of the transcription factor PEBP2/CBF) lack c-Kit+ haematopoietic cell clusters in the dorsal aorta, omphalomesenteric and umbilical arteries, as well as yolk sac vessels. Moreover, endothelial cells sorted from the embryo proper and the yolk sac of AML1-/- embryos are unable to differentiate into haematopoietic cells on OP9 stromal cells, whereas colonies of AML1-/- endothelial cells can be formed in culture. These results strongly suggest that the emergence of haematopoietic cells from endothelial cells represents a major pathway of definitive haematopoiesis and is an event that also occurs in the yolk sac in vivo, as suggested by earlier in vitro experiments.

Animals↗

PubMed2001

Step-wise divergence of primitive and definitive haematopoietic and endothelial cell lineages during embryonic stem cell differentiation.

BACKGROUND: The developmental processes leading from the mesoderm to primitive and definitive haematopoietic and endothelial lineages, although of great importance, are still poorly defined. Recent studies have suggested a model in which common precursors give rise to endothelial progenitors and haematopoietic progenitors, the latter subsequently generating both primitive and definitive haematopoietic lineages. However, this model is contradicted by findings that suggest the emergence of haematopoietic cells from the endothelial lineage. RESULTS: We found sequential steps in the differentiation of FLK1+ mesoderm into haematopoietic and endothelial lineages in an in vitro differentiation system of embryonic stem (ES) cells: (i) the GATA-1+ subset of FLK1+ mesodermal cells loses the capacity to give rise to endothelial cells and is restricted to primitive erythroid, macrophage and definitive erythroid progenitors; (ii) the remaining GATA-1- cells give rise to VE-cadherin+ endothelial cells; and subsequently (iii) multiple definitive haematopoietic progenitors and endothelial cells branch off from a subset of VE-cadherin+ cells. CONCLUSIONS: These observations strongly suggest that the divergence of primitive and multilineage definitive haematopoietic/endothelial lineages occurs first, and then multilineage definitive haematopoietic progenitors arise from VE-cadherin+ endothelial cells in the development of haematopoietic and endothelial cells.

Animals↗

PubMed2001

Simulation of the BP-80 blood pump.

In this study, computational fluid dynamics (CFD) analysis was applied to investigate the flow within a commercially available Biopump, BP-80 (Medtronic, Minneapolis, MN, U.S.A.). The Biopump was selected because, for this purpose, a great number of experimental hemolysis data is available. The process of geometry representation and grid generation was focused on, due to its high impact on the numerical results. This process incorporated the use of three commercially available software packages for three-dimensional computer-aided design (3D-CAD), grid generation, and solving, respectively. For the purpose of validation, the head/flow characteristics of the pump were experimentally obtained and compared to the computed data. The results showed a rough agreement between CFD data and experimental data. Further investigations should cover detailed shear stress analyses and computation of other hemolysis-related quantities.

Computer Simulation↗

PubMed2001

Completion pneumonectomy: current indications, complications, and results.

OBJECTIVE: Completion pneumonectomy is reported to be associated with high morbidity and mortality, especially when done in patients with benign disease. We review our 9 years of experience with this operation to evaluate the postoperative outcome and long-term results of various indications. METHODS: Between January 1990 and December 1998, 66 consecutive patients underwent completion pneumonectomy (6.8% of all pneumonectomies), and their cases were retrospectively reviewed. The indication was benign disease in 17 patients and malignant disease in 49 patients. In patients with malignant indications there were 14 local recurrences, 4 second primary tumors, 5 metastatic diseases, and 26 indications because of incomplete initial resection. RESULTS: There were no intraoperative deaths, and the postoperative mortality rate was 7.6%. Complications were encountered in 32 (53%) patients, without any significant difference between benign indication (71%) and malignant indication (47%; P =.0923). Bronchopleural fistula was encountered in 5 (7.6%) patients, and empyema was encountered in 7 (11%) patients. The actuarial 5-year survival was 57% for all patients, 65% for those with benign indications, and 54% for those with malignant indications (60% for local recurrence, 50% for second primary tumor, and 56% for incomplete resection), without any difference between benign and malignant indications (P =.9478). CONCLUSIONS: Completion pneumonectomy can be performed with acceptable mortality and morbidity, even in patients with benign disease. Patients with preoperative infection can be managed with bronchial stump covering and adequate postoperative drainage. Although complications are common, they can successfully be managed with a proper understanding of them.

Adult↗

PubMed2001

Metabolism of 2-nitrofluorene, 2-aminofluorene and 2-acylaminofluorenes in rat and dog and the role of intestinal bacteria.

1. The in vivo metabolism of 2-nitrofluorene (NF), an environmental pollutant, and 2-aminofluorene (AF) and its acylated derivatives, 2-formylaminofluorene (FAF) and 2-acetylaminofluorene (AAF), was examined in rat and dog. 2. 7-Hydroxy-2-nitrofluorene, 5-hydroxy-2-nitrofluorene, AF, AAF, FAF, 7-hydroxy-2-aminofluorene, 5-hydroxy-2-aminofluorene, 7-hydroxy-2-acetylaminofluorene, 5-hydroxy-2-acetylaminofluorene, 7-hydroxy-2-formylaminofluorene and 5-hydroxy-2-formylaminofluorene were identified as urinary and faecal metabolites of NF in rat and dog. 3. AAF and its hydroxylated derivatives were detected as major metabolites of NF in rat, but FAF and its hydroxylated metabolites were mainly excreted in dog. 4. AF, AAF, FAF and their hydroxylated metabolites were also identified as urinary and faecal metabolites of AF, AAF or FAF in rat, suggesting that AAF and FAF are interconverted via AF. 5. Treatment of rat and dog with antibiotics significantly decreased the urinary and faecal excretion of AF and its derivatives after oral administration of NF, and partly decreased the excretion of acylated metabolites after an oral dose of AF. 6. The caecal contents of untreated rats and some species of intestinal bacteria exhibited nitro-reductase activity toward NF, and acylating activity toward AF, affording AAF and FAF.

2-Acetylaminofluorene↗

PubMed2001

CD44 binds a chondroitin sulfate proteoglycan, aggrecan.

Here we report that CD44 binds a chondroitin sulfate (CS) proteoglycan, aggrecan, a major component of cartilage. Soluble CD44-IgG and CD44(+) cells bound to aggrecan from rat chondrosarcoma and bovine cartilage, immobilized on microtiter plates. In both cases, binding was blocked by a neutralizing anti-CD44 mAb or by the pretreatment of aggrecan with chondroitinase, but not hyaluronidase or keratanase, indicating that CD44 binds aggrecan in a manner dependent on CS side chains of aggrecan and that hyaluronic acid is not involved in the binding. Structural analysis showed that glycosaminoglycans of aggrecan from rat chondrosarcoma and bovine articular cartilage consist of mainly CS A and a mixture of CS A and C respectively. When immobilized on microtiter plates, both CS A and C bound CD44-IgG, and the reaction was specifically inhibited by an anti-CD44 mAb. In addition, aggrecan augmented apoptosis in cells expressing CD44-Fas chimeric molecules in synergy with a non-blocking anti-CD44 mAb IRAWB14.4, suggesting that CD44-aggrecan interaction can induce oligomerization of the chimeric molecules. These results suggest that aggrecan interacts with CD44 to mediate cell adhesion and to trigger oligomerization of CD44 molecules, which may lead to intracellular signaling.

Aggrecans↗

PubMed2001

Exclusively epidural arteriovenous fistula in the cervical spine with spinal cord symptoms: case report.

OBJECTIVE AND IMPORTANCE: We describe the case of an epidural arteriovenous fistula (AVF) in the cervical spine draining only into the epidural and paravertebral plexus. An entirely epidural AVF having such drainage is extremely rare. CLINICAL PRESENTATION: A 24-year-old man presented with a 4-month history of gradually progressive sensory and motor disturbances of the upper and lower extremities. Magnetic resonance imaging and magnetic resonance angiography revealed a peridural vascular lesion within the canal compressing the spinal cord from C5 to T2. Diagnostic angiography revealed a perimedullary and/or dural high-flow AVF, fed mainly by branches of ascending cervical and deep cervical arteries. The fistula drained into the epidural and paravertebral venous plexus without reflux into intradural venous systems. INTERVENTION: Multiple feeders of the AVF were embolized with a Liquid coil and n-butylcyanoacrylate via a two-step procedure. One week after embolization, the AVF was surgically removed. CONCLUSION: Interesting points of this case were the exclusively epidural location of the lesion, the exclusively epidural drainage of the AVF, and the etiology of the symptoms. Venous drainage of the fistula had no relation to any dural or intradural veins. Initially, spinal cord and nerve root compression by extradural veins with varicose dilation seemed to cause the radiculopathy and/or the myelopathy, and subsequent myelopathy caused by spinal venous hypertension was believed to be the main etiology in this case.

Adult↗

PubMed2001

FcgammaRIIa polymorphism in Japanese patients with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an immune complex-mediated disease and organ damage is caused by the deposition of immune complex. Receptors which recognize the Fc portion of immunoglobulin G (FcgammaR) play a key role in the phagocytosis of immune complexes. As the gene encoding for FcgammaR of class IIa (FcgammaRIIa) has two allelic forms, H131 and R131, which differ in their affinity to IgG2, this polymorphism might have implications in handling immune complex. We studied the distribution of the FcgammaRIIa polymorphism in 90 Japanese patients with SLE. We also examined the association between FcgammaRIIa polymorphism and the disease activity of SLE and the histopathological findings of lupus nephritis. FcgammaRIIa polymorphism was determined by PCR and dot blot analysis. The allelic frequency of H131 in patients with SLE was significantly lower (H131/R131 = 0.44/0.56) than that of normal controls (H131/R131 = 0.62/0.38; P < 0.05). No significant association was observed between FcgammaRIIa polymorphism and the clinical parameters for the activity of SLE. There was no association between FcgammaRIIa polymorphism and the histological findings in lupus nephritis. The difference in the distribution of FcgammaRIIa alleles between patients with SLE and normal subjects indicates that this polymorphism is a candidate of susceptibility gene for SLE in Japanese.

Adolescent↗

PubMed2001

Identification of the core protein carrying the Tn antigen in mouse brain: specific expression on syndecan-3.

We isolated glycoproteins carrying the Tn antigen, which was expressed spatiotemporally in the developing mouse brain. The Tn antigen was expressed on two molecular species with a molecular weight from 200 to 350 kDa and 110 to 160 kDa, as judged on SDS-PAGE. Although the two glycoproteins showed different susceptibilities to heparitinase I and solubilities in a salt solution, after treatment with V8 protease they showed the same mobility corresponding to a molecular weight of 90 kDa on SDS-PAGE, suggesting that these two molecules shared a common core protein. Partial N-terminal sequences of the glycoproteins were determined, i.e. AQRXRNENFERPV and ALAAPXAPAMLP, which were identified as the sequences of the N-terminal and central portions of syndecan-3, respectively. Both glycoproteins were reactive to anti-mouse syndecan-3 antibody. These results suggest that one is a soluble syndecan-3 cleaved between mucin-like domain and transmembrane domain, and the other is a membrane-bound syndecan-3 lacking N-terminal glycosaminoglycan attachment sites, and that both glycoproteins have a mucin-like domain characteristic of syndecan-3, in which the Tn antigen may be expressed.

Amino Acid Sequence↗

PubMed2001

Case report: Hypoechoic area as an ultrasound finding suggesting subserosal invasion in polypoid carcinoma of the gall bladder.

Ultrasound studies have demonstrated the gall bladder wall to consist of two or more (usually three) layers. Gall bladder tumours with neither a thinned nor split outermost hyperechoic layer are confined to the mucosa or muscle layer, or have only invaded the shallow subserosa. Differentiation of these two types of tumour has posed difficulties. We report a case of polypoid gall bladder carcinoma invading the shallow subserosa with a thickened outermost hyperechoic layer but a hypoechoic area in the deeper part of the tumour. Ultrasound and pathological correlation in this case demonstrated that the hypoechoic area represented an adenocarcinoma invading the subserosa accompanied by abundant fibrosis.

Adenocarcinoma, Papillary↗

PubMed2001

Monitoring of minimal residual disease in children with acute promyelocytic leukemia by RT-PCR detecting PML/RARalpha chimeric gene: a retrospective study of clinical feasibility.

We studied retrospectively the clinical feasibility of minimal residual disease (MRD) monitoring by reverse transcription-polymerase chain reaction (RT-PCR) detecting the PML/retinoic acid receptor alpha (RARalpha) chimeric gene in children with acute promyelocytic leukemia (APL). MRD monitoring of APL was performed with standard and nested RT-PCR for PML/RARalpha gene, the sensitivity of which was 1 leukemic cell in 10(3)-10(4) and 1 in 10(4)-10(5) cells, respectively. Patients were nine children with APL (average age: 8.3 year; average period of follow-up: 69.2 months) who, after achieving remission with all-trans retinoic acid (ATRA), received treatment either with multidrug chemotherapy or with a combination of chemotherapy and ATRA. Out of six patients treated with multidrug-combined chemotherapy, two patients exhibited PCR positivity after six months of post- remission therapy, which shifted from the detectable range of the nested PCR to that of the standard PCR. These two patients subsequently relapsed and, together with two of the other patients receiving multidrug-combined chemotherapy, underwent allogeneic bone marrow transplantation. No MRD was detected in these patients after transplantation. In the remaining three patients who underwent cyclic treatment with alternative chemotherapy and ATRA, two showed positive RT-PCR at the nested or standard level, respectively, after six months of combined therapy, and one of them relapsed. Overall, three of four patients with MRD detected in post-remission period ultimately relapsed, while all of five patients without detectable MRD had a good prognosis. These findings suggest that impending relapse may be predicted by the detection of preceding PCR positivity with an increasing quantity of the PML/RARalpha mRNA that appears beyond six months of post-remission chemotherapy, with or without combined ATRA therapy.

Adolescent↗

PubMed2001

Progressive renal failure and blindness due to retinal hemorrhage after interferon therapy for hepatitis C virus-associated membranoproliferative glomerulonephritis.

We treated a 67-year-old Japanese woman with membranoproliferative glomerulonephritis (MPGN) and chronic active hepatitis associated with hepatitis C virus (HCV) infection. Treatment commenced with a daily dose of 6 MU IFN alpha-2b for 2 weeks, which was changed to three times weekly thereafter. After 2 weeks, HCV RNA in the serum was undetectable and there was a concomitant reduction in proteinuria. Treatment with IFN alpha-2b was discontinued because of severe headache and fever. Five weeks after the discontinuation of IFN alpha-2b, the patient experienced the sudden onset of visual loss due to retinal hemorrhage. Subsequently, proteinuria and renal function progressively deteriorated though HCV RNA was undetectable. This case exemplifies the need for careful monitoring of renal function and retinal lesions not only in patients receiving IFN but also in those following the discontinuation of IFN treatment.

Aged↗

PubMed2001

Unenhanced CT findings of vascular compromise in association with intussusceptions in adults.

OBJECTIVE: The purpose of this study was to evaluate unenhanced CT findings for predicting the degree of vascular compromise in intussusception observed at surgery. MATERIALS AND METHODS: The imaging studies, clinical records, and surgical and pathologic findings in 25 patients with intussusception were reviewed retrospectively. We evaluated six CT findings based on the abnormalities of each component of intussusception. Presence or absence of these findings was compared with the degree of vascular compromise as observed on pathologic examination, such as edema, ischemia, or necrosis. RESULTS: The hypodense layer was observed in 16 of 18 intussusceptions with various degrees of vascular compromise. A fluid collection surrounded by the returning wall, which was revealed to correspond to trapped peritoneal fluid, was observed in eight of nine intussusceptions with ischemia or necrosis. A gas collection surrounded by the returning wall was observed in two of four intussusceptions with necrosis. Free peritoneal fluid coexisted with a fluid collection surrounded by the returning wall in all the intussusceptions except one. Bowel obstruction was observed in six of nine intussusceptions with ischemia or necrosis. The maximum wall thickness was not related to the degree of vascular compromise. CONCLUSION: The CT findings of a hypodense layer in the returning wall, fluid collection in the space surrounded by the returning wall, and gas collection in the space surrounded by the returning wall can be useful in predicting the degree of vascular compromise in intussusception.

Adolescent↗

PubMed2001

Origin of hematopoietic progenitors during embryogenesis.

It has been widely accepted that hematopoietic and endothelial cell lineages diverge from a common progenitor referred to as the hemangioblast. Recently, analyses of the potential of progenitor cells purified from mouse embryos as well as embryonic stem cells differentiating in vitro resolved intermediate stages between mesodermal cells and committed precursors for hematopoietic and endothelial cell lineages. There are two distinct hematopoietic cell lineages which have different origins, i.e., primitive hematopoietic lineage derived from mesoderm or hemangioblasts and definitive hematopoietic lineage derived from endothelial cells. The endothelium is suggested to provide a milieu in which the definitive hematopoietic lineage acquires multiple potentials.

Animals↗

PubMed2001

Prognostic impact of CD45 antigen expression in high-risk, childhood B-cell precursor acute lymphoblastic leukemia.

To evaluate the clinical implications of CD45 expression in acute childhood lymphoblastic leukemia (ALL), we measured the CD45 expression of blast cells from 133 untreated patients with childhood B-precursor ALL (n = 118) or T-ALL (n = 15). CD45 expression (> or = 20%) was detected in all 15 cases (100%) of T-ALL, and 101 cases (86%) of B-precursor ALL. In 122 cases, the fluorescence intensity of the CD45 expression was measured as a relative value; the ratio of average linear values (RALV) of CD45 on the blasts to that on CD3-positive T-lymphocytes from the same specimen. The expression was more intense in the T-ALL cases than in the B-precursor ALL cases (RALV, mean +/- SE: T-ALL 0.230 +/- 0.04 vs. pro-B ALL 0.150 +/- 0.012/pre-B ALL 0.153 +/- 0.019, p < 0.05). However, the intensity of the CD10, CD19, CD20 and CD34 antigen immunoreactivity did not correlate with the CD45 expression. Patients with hyperdiploidy (chromosome number > 50) showed significantly lower levels of CD45 expression than patients with t(1;19) or normal karyotypes (RALV, mean +/- SE: 0.081 +/- 0.022 vs. 0.133 +/- 0.03/0.143 +/- 0.019, p < 0.05). Other clinical features such as age, gender and WBC count did not correlate with CD45 expression. The prognostic implications of CD45 expression were studied in non-high-risk (low-risk + intermediate-risk) (n = 60) and high-risk patients (n = 52) with B-precursor ALL who had been treated with the risk-directed protocol of ALL-941 trial. Although CD45 expression did not correlate with the event-free survival (EFS) of the non-high-risk patients, there was a significant correlation between the expression levels and the EFS of the high-risk patients: the 3-year EFS rate of the CD45low group (n = 26, RALV = 0.017-0.132) was 88 +/- 7% versus the CD45high group (n = 26, RALV = 0.133-0.450) at 34 +/- 24% (p < 0.05). These results show that the levels of expression of the CD45 antigen on leukemic lymphoblasts are significantly correlated with the clinical features and prognosis of childhood ALL.

Antigens, CD↗