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Biomedical subjects

S Fujii

Publications and source records attributed to S Fujii.

At least 55 records · Page 3Linked to original sources
PubMed2001

Expression of the cell cycle regulator p27(Kip1) in normal squamous epithelium, cervical intraepithelial neoplasia, and invasive squamous cell carcinoma of the uterine cervix. Immunohistochemistry and functional aspects of p27(Kip1).

BACKGROUND: Abnormality of cell cycle regulators and tumor suppressors, such as cyclin dependent kinase inhibitors (cdkIs), has been reported in malignant tumors. The current study was undertaken to examine the involvement of a cdkI, p27(Kip1) (p27), in the neoplastic process of the uterine cervical epithelium. METHODS: Immunohistochemical staining of p27 was performed in samples of normal cervical tissue (30 samples), cervical intraepithelial neoplasias (CINs; 17 samples), and invasive squamous cell carcinoma (SCC; 25 samples). The results were compared with the expression levels of Ki-67, cdk2, and cyclin E. The functional aspects of the p27 protein, such as its ability to bind to cdk2 and the phosphorylation activity of p27-bound cdk2, also were evaluated with an immunoprecipitation and histone H1 kinase assay. RESULTS: In normal cervical epithelia, the expression of p27 was strong in the intermediate and superficial cells but very weak in the parabasal cells. In CIN samples, the expression of p27 was negligible. The expression of p27 in these tissues showed an inverse topologic correlation to that of Ki-67, cdk2, and cyclin E. However, it is noteworthy that the number of p27 positive cells increased in SCC samples that also showed increased expression of Ki-67, cdk2, and cyclin E. The p27 protein in SCC samples was bound to cdk2 and cyclin E. However, cdk2 that was bound to p27 still possessed histone H1 kinase activity. CONCLUSIONS: The expression of p27 may be involved in the growth regulation of the normal squamous epithelium in the uterine cervix. However, aberrant function of p27 expression may occur in invasive SCC of the cervix.

Carcinoma, Squamous Cell↗
PubMed2001

Interleukin-10 promotes the maintenance of antitumor CD8(+) T-cell effector function in situ.

Interleukin-10 (IL-10) is a multifunctional cytokine that can exert suppressive and stimulatory effects on T cells. It was investigated whether IL-10 could serve as an immunostimulant for specific CD8(+) cytotoxic T cell (CTL) in vivo after vaccination and, if so, under what conditions. In tumor prevention models, administration of IL-10 before, or soon after, peptide-pulsed primary dendritic cell immunization resulted in immune suppression and enhanced tumor progression. Injection of IL-10, however, just after a booster vaccine significantly enhanced antitumor immunity and vaccine efficacy. Analysis of spleen cells derived from these latter animals 3 weeks after IL-10 treatment revealed that the number of CD8(+) CD44(hi) CD122(+) T cells had increased and that antigen-specific proliferation in vitro was enhanced. Although cytotoxicity assays did not support differences between the various treatment groups, 2 more sensitive assays measuring antigen-specific interferon-gamma production at the single-cell level demonstrated increases in the number of antigen-specific responder T cells in animals in the vaccine/IL-10 treatment group. Thus, IL-10 may maintain the number of antitumor CD8(+) T cells. In adoptive transfer studies, the ability of IL-10 to maintain CTL function could be enhanced by the depletion of CD4(+) T cells. This suggests that IL-10 mediates contrasting effects on both CD4(+) and CD8(+) T cells that result in either immune dampening or immune potentiation in situ, respectively. Appreciation of this dichotomy in IL-10 immunobiology may allow for the design of more effective cancer vaccines designed to activate and maintain specific CD8(+) T-cell effector function in situ.

Animals↗
PubMed2001

Establishment of an expression cloning system for CD4+ T cell epitopes.

We previously reported an epitope presenting vector, pCI, a derivative of a human invariant chain (Ii) expression vector, in which the class II associated invariant chain peptide (CLIP, Ii p89-101) could be substituted with antigenic peptides. In the current study, we used this vector to develop a new expression cloning system to identify CD4+ T cell epitopes. We inserted double-stranded oligo DNAs of randomized sequences into this vector and prepared an epitope-presenting library which loads randomized 13-mer peptides onto HLA class II molecules coexpressed in COS-7 cells. Utilizing this library, we isolated a cross-reactive epitope recognized by a glutamic acid decarboxylase (GAD) 65-autoreactive T cell clone established from a patient with insulin-dependent diabetes mellitus. Although the newly identified epitope (PVQLSNQWHVVGATF) was far different from the original epitope, GAD65 p116-128 (NILLQYVVKSFDR), it did have the capacity to stimulate the T cell clone comparable to that of the original GAD epitope. Our system may be applicable not only for identifying of cross-reactive epitopes for CD4+ T cells of known specificity, but also for detection of epitopes stimulatory for CD4+ T cells the epitopes of which are unknown.

Amino Acid Sequence↗
PubMed2001

Angiotensin-converting enzyme inhibition attenuates hypofibrinolysis and reduces cardiac perivascular fibrosis in genetically obese diabetic mice.

BACKGROUND: Obesity and insulin resistance are associated with accelerated macrovascular and microvascular coronary disease, cardiomyopathic phenomena, and increased concentrations and activity in blood of plasminogen activator inhibitor type 1 (PAI-1), the primary physiological inhibitor of fibrinolysis. METHODS AND RESULTS: To determine whether hypofibrinolysis in blood and tissues and its potential sequelae could be attenuated pharmacologically, we studied genetically modified obese mice. By 10 weeks of age, obese mice exhibited increases in left ventricular weight and glucose and immunoreactive insulin in blood. PAI-1 activity in blood measured spectrophotometrically was significantly elevated as well. The difference compared with values in lean controls widened by 20 weeks of age. Perivascular fibrosis in coronary arterioles and small coronary arteries was evident in obese mice 10 and 20 weeks of age, paralleling increases in PAI-1 and tissue factor expression evident by immunohistochemical image analysis, in situ hybridization, and reverse transcription-polymerase chain reaction. Inhibition of ACE activity initiated in obese mice 10 weeks of age and continued for 20 weeks arrested the increase in PAI-1 activity in blood and in cardiac PAI-1 and tissue factor mRNA as well as coronary perivascular fibrosis. CONCLUSIONS: Thus, inhibition of proteo(fibrino)lysis and augmented tissue factor expression in the heart precede and may contribute to the coronary perivascular fibrosis seen with obesity and insulin resistance. Furthermore, inhibition of ACE activity can attenuate all 3 phenomena.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2001

Neuronal plasticity in hippocampal mossy fiber-CA3 synapses of mice lacking the inositol-1,4,5-trisphosphate type 1 receptor.

In the present study, we used inositol-1,4,5-trisphosphate (IP3) type 1 receptor (IP3R1) knockout mice to examine the role of this receptor in the induction of LTP, LTD, and DP at mossy fiber-CA3 synapses. No difference in synaptically induced field-EPSPs was seen between the wild-type (IP3R1(+/+)) and IP3R1 knockout mice (IP3R1(-/-)), showing that basic synaptic transmission does not involve IP3R1 activation. Tetanus induced LTP in both wild-type and IP(3)R1(-/-) mice, but the magnitude of LTP was significantly greater in IP3R1(-/-) mice (149.8+/-3.5%, mean+/-S.E.M., n=15) than in wild-type mice (132.4+/-1.5%, n=17), suggesting that the IP3R1 has a suppressive effect on LTP induction. To determine whether this effect involved N-methyl-D-aspartate receptor (NMDAR)-dependent LTP, the effect of tetanus was tested in the present of the NMDAR antagonist, D,L-AP5 (50 microM); under these conditions, the LTP in both IP3R1(-/-) and IP3R1(+/+) mice was not significantly reduced. In addition, group I mGluR activation was shown to be necessary for LTP induction, as the LTP was almost blocked by the group I mGluR antagonist, RS-4CPG (500 microM) in both IP3R1(-/-) (117.6+/-1.7%, n=8) and IP3R1(+/+) (116.9+/-1.8%, n=5) mice. The IP3R1 also plays an essential role in LTD induction, as low-frequency stimulation (LFS) failed to induce LTD in the mutant mice (104.5+/-2.1%, n=10). DP was induced in both IP3R1(-/-) and wild-type mice.

Animals↗
PubMed2001

Antinociceptive action of amlodipine blocking N-type Ca2+ channels at the primary afferent neurons in mice.

We investigated the antinociceptive action of amlodipine, a dihydropyridine derivative, which acts on both L- and N-type voltage-dependent Ca2+ channels (VDCCs), in mice. Intrathecal injection of amlodipine (300 nmol/kg) significantly shortened the licking time in the late phase of a formalin test, while no effect was found with another dihydropyridine derivative, nicardipine (300 nmol/kg). Cilnidipine and omega-conotoxin GVIA also showed marked analgesic effects under the same experimental conditions. Transcripts of alpha1A, alpha1B, alpha1E, alpha1F, alpha1H, beta3, and beta4 subunits were detected by polymerase-chain reaction (PCR) in the dorsal root ganglion, suggesting the existence of a variety of voltage-dependent Ca2+ channels. Electrophysiological experiments showed that amlodipine and cilnidipine inhibit N-type currents in the dorsal root ganglion cells. These results suggest that amlodipine, cilnidipine, and omega-conotoxin GVIA exert their antinociceptive actions by blocking N-type Ca2+ channels in the primary nociceptive afferent fibers. Blocking of the Ca2+ channels results in attenuation of synaptic transmission of nociceptive neurons. Furthermore, it is suggested that some N-type Ca2+ channel blockers might have therapeutic potential as analgesics when applied directly into the subarachnoidal space.

Amlodipine↗
PubMed2001

An allyltitanium derived from acrolein 1,2-dicyclohexylethylene acetal and (eta(2)-propene)Ti(O-i-Pr)(2) as a chiral propionaldehyde homoenolate equivalent that reacts with imines with excellent stereoselectivity. An efficient and practical access to optically active gamma-amino carbonyl compounds.

A chiral allyltitanium compound 2, prepared in situ by the reaction of optically active acrolein 1,2-dicyclohexylethylene acetal (3) with (eta(2)-propene)Ti(O-i-Pr)(2) (1), reacts with a variety of acyclic and cyclic imines 4 in a regiospecific way to afford alpha-addition products 5 as a mixture of the E- and Z-isomers in good combined yield, where the former is predominant in a ratio of 92:8 to >95:5. The mixture of (E)- and (Z)-5 and pure (E)-5 which could be isolated in several cases were respectively converted to the corresponding beta-amino ester 6 to confirm the absolute configuration and enantiomeric purity. The ee of the newly formed asymmetric center of 5 is more than 78% for the mixture of (E)- and (Z)-5 and more than 96% for pure (E)-5. By taking advantage of the versatility of the vinyl ether moiety in 5, optically active gamma-amino aldehydes 8, gamma-amino aldehyde acetals 7 and 10, gamma-amino acids 9, beta-amino esters 6, and pyrrolidinoisoquinolines 12 were readily prepared. In the reaction of 2 with optically active alpha-silyloxyimine 4n, remarkable double stereodifferentiation was observed; thus, the reaction of 2 derived from (S,S)- or (R,R)-3 provided syn- and anti-5n in a ratio of 55:45 or 0:100, respectively. Meanwhile, the stereochemistry of the product in the reaction of 2 with beta-silyloxyimine 4o was controlled mainly by 2. Thus, the reaction of beta-silyloxyimine 14 with 2 derived from 1 and (R,R)-3 afforded gamma-silyloxyimine 15 with 92% diastereoselectivity, from which 4-amino-6-hydroxypentadecanal dimethyl acetal (13), a key intermediate for the synthesis of batzelladine D, was synthesized.

Journal Article↗
PubMed2001

Acute and chronic nicotine exposure reverse age-related declines in the induction of long-term potentiation in the rat hippocampus.

Long-term potentiation (LTP) is widely considered to be the cellular substrate of learning and memory. The induction of LTP becomes more difficult with age in parallel with declining learning and memory ability. Because nicotine improves learning and memory in aged rats, we examined the effects of acute and chronic nicotine exposure on age-related declines in LTP induction. We found that acute nicotine exposure lowered the threshold for LTP induction in the aging hippocampus. The effect of nicotine was mimicked by the alpha7 nicotinic acetylcholine receptor (nAChR) antagonist methyllycaconitine and blocked by the non-alpha7 nAChR antagonist dihydro-beta-erythroidine, suggesting that both nicotine-mediated desensitization of alpha7 nAChRs and activation of non-alpha7 nAChRs contribute to the nicotine effect. The non-alpha7 nAChR agonist A85380 that facilitates the induction of LTP in the young hippocampus had no effect, however, suggesting that at least one pathway involving non-alpha7 nAChRs was altered by aging. Chronic nicotine treatment of aged rats also lowered the threshold for LTP induction and acute nicotine exposure lowered the threshold further in the chronic-nicotine-treated aged hippocampus. These results not only suggest that the mechanisms mediated by acute and chronic nicotine exposure are different, but also demonstrate that age-associated declines in LTP induction can be reversed with nicotine treatment.

Aconitine↗
PubMed2001

Nicotine accelerates reversal of long-term potentiation and enhances long-term depression in the rat hippocampal CA1 region.

In the hippocampal CA1 region, low-frequency stimulation (LFS; 200 pulses at 1 Hz) causes reversal of long-term potentiation (depotentiation, DP) and long-term depression (LTD), both of which are thought to be the cellular substrate of learning and memory. Because nicotine enhances learning and memory, we examined if nicotine modulates DP and LTD in the hippocampal CA1 region. Bath application of nicotine during LFS accelerated DP, that is, potentiated synaptic responses in hippocampal CA1 neurons returned to pre-tetanic control levels more rapidly in the presence of nicotine. Because a similar acceleration of DP was observed using the alpha7 nicotinic acetylcholine receptor (nAChR)-selective antagonist methyllcaconitine (MLA), the nicotine effect appeared to be at least partly mediated by nicotine-induced desensitization of alpha7 nAChRs. Delivery of LFS in the presence of nicotine or MLA also depressed synaptic responses in a naive pathway and facilitated LTD, that is, the magnitude of LTD was larger when the drug was present during LFS. Thus, these results demonstrate that nicotine facilitates DP and LTD, which may represent, at least in part, the cellular mechanism underlying nicotine-induced cognitive enhancement.

Aconitine↗
PubMed2001

Human ovarian surface epithelial (OSE) cells express LH/hCG receptors, and hCG inhibits apoptosis of OSE cells via up-regulation of insulin-like growth factor-1.

Gonadotropins including luteinizing hormone (LH) or human chorionic gonadotropin (hCG) have been implicated as playing an important role in the development of epithelial ovarian carcinomas, most of which are believed to originate from the ovarian surface epithelium (OSE). To address this issue, we examined the expression of LH/hCG receptors and the influence of hCG on cell proliferation and on the apoptosis of cultured human OSE cells. RT-PCR and binding assay revealed that OSE cells express the LH/hCG receptor mRNA and have specific binding activity for hCG. Treatment with hCG stimulated the proliferation of OSE cells in a dose-dependent manner. In addition, hCG treatment inhibited the apoptosis of OSE cells induced by serum deprivation. Among the apoptosis-related genes, hCG treatment did not change the mRNA levels of bcl-2, bax and IGF-1 receptor but significantly increased that of IGF-1. Treatment with IGF-1 alone also suppressed the apoptosis of OSE cells, and treatment by hCG along with neutralization antibody against IGF-1 receptor reversed the anti-apoptotic effect of hCG. Accordingly, LH/hCG signaling followed by up-regulation of IGF-1 is involved in the inhibition of apoptosis of OSE cells, the possible histogenetic origin of epithelial ovarian carcinomas.

Apoptosis↗
PubMed2001

Expression of Ly-6A/E in the mouse uterus during implantation period.

To investigate the molecular mechanisms of implantation, we constructed a complementary DNA library of mouse uterus enriched with pregnancy-induced genes by subtractive hybridization and polymerase chain reaction. One of the isolated clones was a part of complementary DNA for the Ly-6A/E. Ly-6A/E is reported to be differentially expressed on hematopoietic stem cells and some lymphoid and nonlymphoid tissues, mediate cell-cell adhesion on lymphoid cells, and associate with cell proliferation and angiogenesis of tumor cells. Northern blot, in situ hybridization, and immunohistochemical analyses demonstrated that the Ly-6A/E mRNA and protein were expressed in the endometrial epithelial cells as well as myometrial cells and vascular endothelial cells in the uterus of nonpregnant mouse. The expression was downregulated in luminal epithelial cells during pregnancy days 1-5, while it was upregulated in decidualized stromal cells around the implanted embryo at the time of implantation. The signals were primarily localized in stromal cells at the mesometrial pole on day 9. The increased expression was also observed in stromal cells of the embryo-transferred uterus and artificially-induced deciduoma, indicating that the expression of Ly-6A/E in the endometrial cells is concurrent with decidualization. These findings suggest that Ly-6A/E plays a role in embryo implantation.

Animals↗
PubMed2001

An analysis of relapsed breast cancer in patients previously treated with breast conserving surgery.

BACKGROUND: Recent advances in breast surgery have focused on breast conserving surgery in combination with radiotherapy. In the present study, we examine by retrospective analysis 105 patients with breast cancer who received breast conserving surgery for factors influencing disease free survival. METHODS: The analysis was performed on 105 patients with breast cancer who received breast conserving surgery in our department, including 38 patients without radiotherapy and 67 patients treated with radiotherapy. The disease-free survival of the patients was analyzed using the Kaplan-Meier method. The relapsed patients were assessed by examining pathological features and gene expression by immunohistochemical staining. RESULTS: There was no significant difference in the disease free survival at 5 years between patients without radiotherapy (89.6%) and with radiotherapy (94.5%). Relapse after breast conserving surgery was found in 6 patients including 4 patients without radiotherapy and 2 patients with radiotherapy. Local relapse and bone metastasis were found in 4 (3.8%) and 2 patients, respectively. Among the 4 local relapses, 1 patient had received radiotherapy and 3 patients had not. There was no significant difference between the type of relapse in terms of lymph node metastasis, hormone receptor, nuclear grade and intraductal component, but more vessel invasion was observed in the 2 cases with bone metastasis. The overexpression of apoptosis and angiogenesis genes such as p53, Bax, Bcl-XL, Bcl-2 and VEGF was not common in the relapsed patients, whereas the overexpression of drug resistance genes, either P-gp or MRP1, was found in the all patients. CONCLUSIONS: Although radiotherapy may reduce the incidence of local relapse and increase disease free survival after breast conserving surgery, the development of an effective adjuvant chemotherapy based on drug resistance markers, is also required.

Adult↗
PubMed2001

Concurrent Hodgkin's disease (mixed cellularity type) and T-cell chronic lymphocytic leukemia/prolymphocytic leukemia.

We describe a patient with leukopenic T-cell chronic lymphocytic leukemia/prolymphocytic leukemia (T-CLL/PLL), according to the Revised European-American Classification of Lymphoid Neoplasms. This patient simultaneously developed classic Hodgkin's disease (HD), a combination previously unreported. The leukemic cells were small and mature, did not have cytoplasmic granulation, and appeared similar to B-cell chronic lymphocytic leukemia. Immunophenotyping of the bone marrow-infiltrating cells revealed a postthymic suppressor/cytotoxic phenotype of CD2+, CD3+, CD4, CD5+, CD8+, CD25-, TCR-alpha beta. A lymph node biopsy showed the histological features of HD (mixed cellularity) with infiltrating CD8+ lymphocytes, and immunohistochemical examination revealed the following phenotype of Reed-Sternberg cells: LeuM1/CD15+, BerH2/CD30+, L26/PanB-, UCHL-1/CD45RO-, cyCD3-, CD4, CD8-, CD20-, CD79a-, EMA-, EBER-1+, LMP-1+. Southern blot analysis of the bone marrow and lymph node revealed the same rearrangement of bands of T-cell-receptor genes. Although the HD was treated with chemotherapy that resulted in complete remission, the T-PLL/CLL took an indolent course. This case may suggest the existence of a subtype of T-CLL/PLL with leukopenia and an indolent clinical course. Both diseases were believed to be independent and not a transformation of one to the other.

Aged↗
PubMed2001

Severe congenital cytomegalovirus infection with fetal hydrops in a cytomegalovirus-seropositive healthy woman.

We report the case of a woman whose two consecutive pregnancies resulted in intrauterine fetal death due to severe congenital cytomegalovirus infection. In both pregnancies, congenital cytomegalovirus infection was prenatally diagnosed on the basis of detection of cytomegalovirus DNA and specific IgM in cord blood. This case suggests that severe congenital cytomegalovirus infection can occur even in seropositive healthy women.

Adult↗
PubMed2001

Krukenberg tumor from an occult appendiceal adenocarcinoid: a case report and review of the literature.

Appendiceal neoplasms with ovarian metastasis are rare. A 35-year-old woman with a left ovarian tumor underwent left salpingo-oophorectomy, partial resection of the right ovary, and a total hysterectomy. Pathological diagnosis of both ovaries was typical, Krukenberg tumor with signet-ring cells, and the second laparotomy revealed an occult appendiceal tumor to be the primary lesion. The appendix showed no evidence of malignant change of the mucosa, but the tumor cells were observed infiltrating from the basiglandular region into the underlying stroma, associated with mucocele. Although, argentaffin and argyrophil staining were negative, a few tumor cells showed immunohistochemical positivity for Chromogranin A. Accordingly, the tumor was diagnosed as adenocarcinoid rather than adenocarcinoma of the appendix. A review of the literature showed less than 40 cases of metastatic ovarian tumor from appendiceal primary, one-third of which were occult and could be detected at the second laparotomy. Cisplatin-based chemotherapy may have partial effect in the treatment of patient with adenocarcinoid tumor.

Adult↗
PubMed2001

Combination effect of adenovirus-mediated pro-apoptotic bax gene transfer with cisplatin or paclitaxel treatment in ovarian cancer cell lines.

To develop a novel therapeutic strategy for ovarian cancer, we constructed a recombinant adenovirus which highly expresses pro-apoptotic Bax protein and examined its therapeutic effect on a series of ovarian cancer cell lines: A2780, A2780/cDDP, OVCAR-3 and SK-OV-3. A recombinant adenovirus carrying the Bax-alpha gene (AxCALNKYbax) induced high expression of the Bax-alpha protein in all the cell lines. The cytotoxic effect of Bax was observed in three ovarian cancer cell lines: the per cent reduction in the number of cells was 40.0% for cisplatin-sensitive A2780, 50.0% for cisplatin-resistant A2780/cDDP, and 64.8% for marginally cisplatin-resistant OVCAR-3. In contrast, it was only 12.3% for cisplatin-resistant SK-OV-3. Cisplatin-resistant A2780/cDDP had a p53 mutation and exhibited attenuated Bax induction after cisplatin treatment, which may explain why supplementation of Bax was effective in this chemoresistant ovarian cancer. Combination with cisplatin or paclitaxel enhanced the cytotoxic effect of Bax induction in all but one cell line including cisplatin-resistant A2780/cDDP. It appears that adenovirus-mediated Bax induction, with or without combination with conventional chemotherapy, useful strategy for the treatment of ovarian cancer.

Adenoviridae↗