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Biomedical subjects

Y Taketani

Publications and source records attributed to Y Taketani.

At least 91 records · Page 5Linked to original sources
PubMed2000

Theoretical basis for herbal medicines, Tokishakuyaku-san and Sairei-to, in the treatment of autoimmunity-related recurrent abortion by correcting T helper-1/T helper-2 balance.

PROBLEM AND METHOD OF STUDY: To get insight into the basis for the empirical usage of herbal medicines in the treatment of recurrent abortion, we examined whether Tokishakuyaku-san (Toki) and Sairei-to (Sai) modulate T helper-1 (Th1) and T helper-2 (Th2) cytokine release from peripheral blood mononuclear cells (PBMCs). The effects of these medicines were investigated as related to human leukocyte antigen (HLA)-G, a non-classical HLA class I antigen expressed on trophoblasts and a putative crucial player involved in fetomaternal immune interplay. RESULTS: Toki and Sai increased the release of Th1 group cytokines, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma while preserving the inhibitory effect of HLA-G on the release of these cytokines. As for Th2 group cytokine release, Toki was without effect in modulating interleukin (IL)-4 release, regardless of the presence of HLA-G, whereas Sai nullified the effect of the presence of HLA-G to stimulate the release of IL-4 without affecting its release in the absence of HLA-G. CONCLUSION: Toki and Sai may have therapeutic potential, particularly in autoimmunity-related recurrent abortion where Th2 response is pathologically enhanced, but not in recurrent abortion involving alloimmune fetomaternal derangement, a condition of, rather, an enhanced Thl response.

Abortion, Habitual↗
PubMed2000

A case of XY pure gonadal dysgenesis with 46,XYp-/47,XXYp- karyotype whose gonadoblastoma was removed laparoscopically.

A case of pure gonadal dysgenesis was investigated. The patient was an 18-year-old Japanese woman with a history of primary amenorrhea. She had poorly developed breasts, a hypoplastic uterus, a normal vagina and infantile genitalia. The patient's karyotype was 46,XYp-/ 47,XXYp-. Microsatellite analysis revealed that the X chromosomes of this patient originated from one of the two maternal X chromosomes. DNA analysis of the Y chromosome revealed that she had a deletion of SRY (the sex-determining region on the Y chromosome). She underwent laparoscopic gonadectomies with a final pathology consistent with gonadoblastoma. Laparoscopic surgery is recommended as it is much less invasive and associated with rapid postoperative recovery.

Adolescent↗
PubMed2000

Polymorphisms of RhD(Va) and a new RhD(Va)-like variant found in Japanese individuals.

BACKGROUND AND OBJECTIVES: Red cell type RhD(Va) lacks epD1 and 5 and is encoded by hybrid RHD-CE(5)-D alleles. We analyzed RhD(Va) and RhD(Va)-like samples in Japanese blood donors. MATERIALS AND METHODS: Ten RhD(Va) samples lacked epD1 and 5 and 3 RhD(Va)-like variants also lacked, epD2 and a part of 6/7. We identified the full-length nucleotide sequences of the complementary DNA (cDNA) synthesized from 4 samples: 3 of type D(Va) and the 4th a D(Va)-like variant. RESULTS: Although their sequences differed from each other, all the substitutions were exclusively in exon 5. Three D(Va) samples had hybrid RHD-CE(5)-D alleles, but the D(Va)-like variant had a unique nucleotide substitution with a single amino acid change, E233K. Exon 5 of the genomic DNA from all 13 samples was analyzed by sequencing. No other sequences were identified. CONCLUSION: All RhD(Va) and RhD(Va)-like variants had the substitution for E233. E233 seems to be a determinant of epD1 and 5. A new category of RhD variant, DYO, was identified.

Amino Acid Substitution↗
PubMed2000

Prevalence of endometriosis in ovarian cancer.

Endometriosis may be the precursor of clear cell or endometrioid ovarian cancer. In this review, we focus on the prevalence of endometriosis in ovarian cancer and related clinical and epidemiological issues. According to 15 published reports, the rank order of the prevalence of endometriosis in each histologic type was clear cell (39.2%) > endometrioid (21.2%) > serous (3.3%) > mucinous type (3.0%). The high prevalence of endometriosis in clear cell and endometrioid types is a consistent finding in Japan and western countries. However, the incidence of the clear cell type is much higher (15-20% vs. 7-8%), and that of the endometrioid type is lower (7-16% vs. 18-26%), in Japan compared with western countries. This review is also concerned with the relationship between the presence of ovarian endometriosis and clinical features such as age, parity, menopausal status, clinical stage, and survival in ovarian cancer patients.

Adenocarcinoma, Clear Cell↗
PubMed2000

Inhibition of human epithelial ovarian cancer cell growth in vitro by somatostatin analog RC-160.

In this study, we investigated the effects of somatostatin analog RC-160 on the growth of the OV-1063 human epithelial ovarian cancer cell line in vitro. RC-160 inhibited cell proliferation, as measured by cell number, and [(3)H]thymidine incorporation into DNA at 10(-9)-10(-5) M. In OV-1063 cells, (125)I-labeled RC-160 was bound to one class of specific, saturable binding sites with high affinity (K(d) = 0.2 +/- 0.03 nM) and low capacity (5,500 binding sites per cell). (125)I-labeled RC-160 could be displaced by unlabeled RC-160. Ligand binding was dependent on time and temperature. Receptor internalization assay showed that the ligand-receptor complex was internalized at 37 degrees C, which indicates the presence of biologically active somatostatin receptors on OV-1063 cells. These results suggest that somatostatin analog RC-160 can suppress the growth of OV-1063 human epithelial ovarian cancer cells by a direct action and that the inhibitory effect of somatostatin analog is mediated through the high-affinity somatostatin receptors.

Antineoplastic Agents↗
PubMed2000

Evidence for the presence of angiogenin in human follicular fluid and the up-regulation of its production by human chorionic gonadotropin and hypoxia.

Angiogenesis is an essential event during the development of the ovarian follicle and ensuing formation of the corpus luteum. We investigated the presence of angiogenin, a potent inducer of angiogenesis, and the regulatory mechanisms of its production in the human ovary. Follicular fluid (FF) and granulosa cells (GCs) were collected from women undergoing in vitro fertilization and embryo transfer. The presence of angiogenin in FF and GCs was demonstrated by Western blot analysis. The production of angiogenin by cultured GCs was stimulated with the addition of human CG or cAMP or under the hypoxic milieu. Concentrations of angiogenin in FF from an individual follicle were positively correlated with those of progesterone, but not estradiol and testosterone. Given the presence of angiogenin in FF and up-regulation of its production by human CG and hypoxia, it seems logical to assume that angiogenin may play a role as a local angiogenic factor in the human ovary.

Adult↗
PubMed2000

Comparison of the effects of add-back therapy with various natural oestrogens on bone metabolism in rats administered a long-acting gonadotrophin-releasing hormone agonist.

The hypoestrogenic state induced by gonadotrophin-releasing hormone agonist (GnRHa) has been shown to be effective in the treatment of oestrogen-dependent disorders but to induce bone loss. Adding back low doses of oestrogen in GnRHa therapy has been proposed to prevent bone loss. The purpose of this study is to assess the efficacy of add-back therapy with different natural oestrogens such as oestrone (OE(1)), oestradiol (OE(2)) and oestriol (OE(3)). Three-month-old female rats (250 g) were subcutaneously administered microcapsules of leuprorelin acetate in doses of 1 mg/kg of body weight every 4 weeks. GnRHa therapy lasted 16 weeks, and pellets of OE(1), OE(2) or OE(3) (0.5 mg/pellet, 60 day release), as an add-back agent, were implanted at 8 weeks of treatment. At the end of treatment, GnRHa alone decreased bone mineral density of the femur and lumbar vertebrae, and increased serum levels of bone metabolic markers such as alkaline phosphatase and osteocalcin levels. As for cancellous bone histomorphometry, GnRHa decreased bone volume while it increased osteoid volume, osteoid surface, eroded surface, mineral apposition rate and bone formation rate. All the oestrogens tested prevented these changes caused by GnRHa therapy. GnRHa induced a significant increase in body weight and a marked reduction in uterine weight, which was not observed in OE(1) or OE(2) add-back group. Body weight and uterine weight of the OE(3) add-back group were the same as those of the GnRHa group. These findings indicate that GnRHa induces high turnover bone loss which can be prevented by concomitant administration of natural oestrogens such as OE(1), OE(2) and OE(3) to the same extent. In addition, OE(3) is unique in that it is much less effective than OE(1) and OE(2) in blocking body weight gain and in promoting growth of uterine tissues. Because of its tissue-selective actions, OE(3) could be considered as one of the most appropriate oestrogens used for GnRHa add-back therapy.

Alkaline Phosphatase↗
PubMed2000

Pregnancy rates after laparoscopic treatment. Differences related to tubal status and presence of endometriosis.

OBJECTIVE: To examine how preexisting tubal adhesions and endometriosis affect pregnancy outcome after laparoscopic treatment in infertile women with no apparent causes of infertility other than tubal factors. STUDY DESIGN: Pregnancy outcomes in 186 infertile women for a follow-up period of 18 months after laparoscopy were analyzed. Laparoscopic manipulations consisted of adhesiolysis of tubes and removal of endometriotic lesions. RESULTS: The patients were classified into three groups, those with no tubal adhesions (group A, n = 83), unilateral tubal adhesions (group B, n = 46) and bilateral tubal adhesions with at least one tube patent (group C, n = 57). The cumulative pregnancy rate in group C (13.2%) was lower than in groups A (41.8%) and B (45.7%) 18 months after laparoscopy. The average time to conception in group A (6.7 +/- 0.8 months) tended to be shorter than that in group B (10.6 +/- 1.2 months). In group A, pregnancy rates were essentially the same between minimal/mild endometriosis and moderate/severe endometriosis. Regarding group B, women with minimal/mild endometriosis exhibited significantly higher pregnancy rates than those with moderate/severe endometriosis, while pregnancy rates in women without endometriosis fell in between. CONCLUSION: Pregnancy rates after laparoscopic treatment are different in relation to tubal status and the presence of endometriosis.

Adult↗
PubMed1999

Growth suppression of human ovarian cancer cells by adenovirus-mediated transfer of the PTEN gene.

A tumor suppressor gene on chromosome 10q23, PTEN, encodes a phosphatidylinositol phosphatase that antagonizes activation of the phosphatidylinositol 3'-kinase-mediated pathway involved in cell growth. A gene encoding the catalytic subunit of phosphatidylinositol 3'-kinase (PIK3CA) is frequently activated in ovarian cancers; therefore, overexpression of the PTEN product through gene transfer might be an effective strategy for treating ovarian cancers. To test the potential for this type of gene therapy, we constructed a recombinant adenovirus encoding wild-type PTEN and examined its effects on nine cell lines derived from human ovarian carcinomas. Transduction of the PTEN gene significantly inhibited growth of six of these cell lines compared with infection with virus alone, and the degree of inhibition correlated with the efficiency of gene transfer as determined by beta-galactosidase assay. Results of flow cytometry suggested that the observed effects were mediated by two mechanisms, apoptosis and/or arrest in the G1 phase of the cell cycle, and that high adenoviral transduction efficiency of cells was associated with induction of apoptosis. We also found that the level of transcription of Integrin alpha(v) in ovarian cancer cells correlated with the efficiency of transduction (P = 0.014) and with the degree of growth inhibition after PTEN gene transfer (P = 0.009). These findings carry significant implications for adenovirus vector-based PTEN gene therapies for ovarian cancers.

Adenoviridae↗
PubMed1999

Regulation of intestinal Na+-dependent phosphate co-transporters by a low-phosphate diet and 1,25-dihydroxyvitamin D3.

In a study of the rat intestinal P(i) transport system, an activator protein for rat Na/P(i) co-transport system (PiUS) was isolated and characterized. We also investigated the effects of restriction of vitamin D and P(i) (two of the most important physiological and pathophysiological regulators of P(i) absorption in the small intestine) on intestinal P(i) transport activity and the expression of Na/P(i) co-transporters that are expressed in rat small intestine. Rat PiUS encodes a 424-residue protein with a calculated molecular mass of 51463 Da. The microinjection of rat PiUS into Xenopus oocytes markedly stimulated Na(+)-dependent P(i) co-transport activity. In rats fed with a low-P(i) diet, Na(+)-dependent P(i) co-transport activity was increased approx. 2-fold compared with that of rats fed a normal P(i) diet. Kinetic studies demonstrated that this increased activity was due to an elevation of V(max) but not K(m). The PiUS mRNA levels showed an approximate doubling in the rats fed with the low-P(i) diet compared with those fed with the normal P(i) diet. In addition, after the administration of 1, 25-dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] to vitamin D-deficient animals, the P(i) uptake was significantly increased in the Na(+)-dependent component in the brush border membrane vesicle (BBMV) at 24 and 48 h. In addition, we found a further high-affinity Na/P(i) co-transport system in the BBMV isolated from the vitamin D-replete animals. The levels of type III Na/P(i) co-transporter PiT-2 mRNA were increased 24 and 48 h after 1,25-(OH)(2)D(3) administration to vitamin D-deficient animals, whereas PiUS and the type IIb Na/P(i) co-transporter mRNA levels were unchanged. In conclusion, we first cloned a rat activator protein, PiUS, and then studied its role along with that of other type III Na/P(i) co-transporters. PiUS and PiT-2 might be important components in the regulation of the intestinal P(i) transport system by P(i) restriction and 1,25-(OH)(2)D(3).

Amino Acid Sequence↗
PubMed1999

Identification of regulatory sequences and binding proteins in the type II sodium/phosphate cotransporter NPT2 gene responsive to dietary phosphate.

Dietary phosphate (P(i)) is a most important regulator for renal P(i) reabsorption. The type II sodium-dependent phosphate (Na/P(i)) cotransporters (NPT2) are located at the apical membranes of renal proximal tubular cells and major functional transporters associated with renal P(i) reabsorption. The consumption of a low-P(i) diet induces the synthesis of NPT2, whereas a high P(i) diet decreases it. The molecular mechanisms of regulation by dietary P(i) are not yet known. In this report, in weaning mice fed a low-P(i) diet for 4 days, the NPT2 mRNA level was increased 1.8-fold compared with mice fed a normal P(i) diet. This increase was due to an elevation of the transcriptional activity. In the NPT2 gene promoter, the DNA footprint analysis showed that six regions were masked by the binding protein, but at the position -1010 to -985 upstream of the transcription start site, the binding clearly responded to the levels of dietary P(i). The phosphate response element (PRE) of the NPT2 gene was found to consist of the motif related to the E box, 5'-CACGTG-3'. A yeast one-hybrid system was used to clone a transcription factor that binds to the PRE sequences in the proximal promoter of the NPT2 gene. Two cDNA clones that encoded protein of the mouse transcription factor muE3 (TFE3) were isolated. This is a DNA-binding protein that activates transcription through the muE3 site of the immunoglobulin heavy chain enhancer. TFE3 antibody completely inhibited the binding to the PRE. The coexpression of TFE3 in COS-7 cells transfected with the NPT2 gene promoter markedly stimulated the transcriptional activity. The feeding of a low P(i) diet significantly increased the amount of TFE3 mRNA in the kidney. These findings suggest that TFE3 may participate in the transcriptional regulation of the NPT2 gene by dietary P(i).

Animals↗
PubMed1999

Complete DNA sequence and characterization of a 330-kb VNTR-rich region on chromosome 6q27 that is commonly deleted in ovarian cancer.

We report the complete genomic DNA sequence and the characterization of a 330-kb region on chromosome 6q27 that is often deleted in ovarian cancers. Using computer programs to predict exonic sequences, we isolated four novel genes, HGC6.1-4, as well as the known AF-6 gene. None of the deduced products of the novel genes exhibited significant homology to previously known proteins. We also identified ten microsatellites and 12 different VNTR sequences within the target region. HGC6.3 contained a VNTR within a coding exon, each repeat consisting of 42 nucleotides; the predicted 14-amino-acid consensus unit is MTPTVFSSQHTAGG. At least nine different sizes of this VNTR locus were detected among 20 unrelated DNA samples from caucasians. The polymorphic markers and the transcript map documented here may contribute to identification of novel genes or allelic aberrations associated with the development of ovarian cancers.

Amino Acid Sequence↗
PubMed1999

Balance of IgG subclasses toward human papillomavirus type 16 (HPV16) L1-capsids is a possible predictor for the regression of HPV16-positive cervical intraepithelial neoplasia.

Human papillomavirus type 16 (HPV16) is known to be a major causative agent of cervical cancer. To test the hypothesis that an enhanced Th1 response favors the natural course of cervical intraepithelial neoplasia (CIN), we measured IgG subclasses toward HPV16 L1-capsids because IgG1/IgG2 balance reflects Th2 and Th1 responses, respectively. We examined IgG2/IgG1 ratios in sera from 67 anti-HPV16 L1-positive women; 18 were cytologically normal women, 29 were CIN patients, and 20 were cervical cancer patients. The IgG2 dominance (IgG2/IgG1 ratio >1) was observed in 94, 48, and 5%, respectively (p < 0.001). The regression rate of CIN lesions was significantly different between patients with and without IgG2 dominance: 83.3% (5/6) versus 16.7% (1/6), respectively (p < 0.05). These findings raise the possibility that IgG2 dominance toward HPV16 L1-capsids, i.e., Th1 dominance, may be a useful marker to predict viral clearance or the regression of HPV16-positive CIN.

Capsid↗
PubMed1999

Visualization of the endometrium by intrauterine sonography.

Thirty-five women with normal menstrual cycles underwent transvaginal and high-frequency (15- or 20-MHz) intrauterine sonographic examinations for the assessment of the endometrium. Five sonographic patterns of endometrium were recognized by both sonographic techniques, but the pattern visualized differed between techniques in 9 women (26%). The higher resolution of intrauterine sonography provided more detail of the endometrium. Our preliminary experience indicates that high-frequency intrauterine sonography enables more detailed visualization of changes in the endometrium during the menstrual cycle than does transvaginal sonography.

Adult↗
PubMed1999

Cellular sensitization to cisplatin and carboplatin with decreased removal of platinum-DNA adduct by glucose-regulated stress.

PURPOSE: Stress conditions, such as glucose starvation and hypoxia, that induce glucose-regulated proteins (GRPs) in cells, are seen in most solid tumors. These conditions have been shown to cause cellular resistance to multiple anticancer drugs, such as etoposide, doxorubicin, and camptothecin. We examined the effect of the GRP-inducing conditions on cellular sensitivity to cisplatin and carboplatin, which are widely used drugs against solid tumors. METHODS: We generated the GRP-inducing culture conditions by exposing cells to 2-deoxyglucose (2DG), calcium ionophore A23187 and tunicamycin, and examined cellular sensitivity to cisplatin and carboplatin under these conditions. We next measured platinum accumulation and DNA-bound platinum in 2DG-stressed cells after cisplatin exposure. RESULTS: The GRP-inducing stress conditions led to cellular sensitization to cisplatin and carboplatin. This sensitization was reversible, as the cellular sensitivity returned to normal levels 12 h after removal of 2DG. Platinum accumulation and DNA-bound platinum that were found immediately after exposure to cisplatin for 1 h were slightly increased in 2DG-stressed cells as compared with nonstressed cells. After a drug-free recovery incubation of 8 h, the DNA-bound platinum in the nonstressed cells was reduced by 33% while the amount in the 2DG-stressed cells was sustained at the initial levels. CONCLUSIONS: These results indicated that the decreased removal of platinum-DNA adducts was associated with increased sensitivity to cisplatin and carboplatin in the stressed cells. The sensitization of cancer cells under the GRP-inducing stress conditions would explain, in part, the clinical potency of platinum drugs against solid tumors.

Antineoplastic Agents↗
PubMed1999

Inhibition of human endometrial cancer cell growth in vitro and in vivo by somatostatin analog RC-160.

OBJECTIVE: Our purpose was to investigate the effect of the somatostatin analog RC-160 on the growth of the HEC-1 human endometrial cancer cell line in vivo and in vitro. STUDY DESIGN: Nude mice bearing subcutaneous implanted HEC-1 tumors were treated for 25 days with RC-160 (100 microgram/d) delivered by osmotic minipumps. In cultured HEC-1 cells radioreceptor assay of somatostatin was performed, and the expression of messenger ribonucleic acid for somatostatin receptor subtypes (somatostatin receptors 1-5) was analyzed by reverse transcription-polymerase chain reaction. The effects of RC-160 on epidermal growth factor-stimulated cell proliferation and tyrosine phosphorylation of epidermal growth factor receptor were examined by colorimetric assay and Western blotting, respectively. RESULTS: The treatment with RC-160 resulted in a significant decrease in tumor volume, tumor weight, and serum insulin-like growth factor I levels compared with those values in control animals. The presence of high-affinity somatostatin binding sites and the expression of somatostatin receptor 2 and somatostatin receptor 3 messenger ribonucleic acid were demonstrated in HEC-1 cells by radioreceptor assay and reverse transcription-polymerase chain reaction, respectively. Epidermal growth factor-stimulated proliferation of HEC-1 cells was inhibited by RC-160 in a dose-dependent manner. Western blotting revealed that epidermal growth factor-induced tyrosine phosphorylation of epidermal growth factor receptor was inhibited by RC-160, which suggests that the direct inhibitory effect of RC-160 on HEC-1 cell growth might be mediated in part by interference with epidermal growth factor receptor phosphorylation. CONCLUSION: These results indicate that somatostatin analog RC-160 inhibits the growth of HEC-1 human endometrial cancer cells, thus implying its potential clinical utility in treating endometrial cancer.

Animals↗
PubMed1999

A case of ovarian hyperstimulation syndrome in which antithrombin III deficiency occurred because of its loss into ascites.

OBJECTIVE: To present a case of ovarian hyperstimulation syndrome in which antithrombin III activity in plasma was decreased and in ascites was increased. DESIGN: Case report. SETTING: Hospital-based clinic for reproductive medicine. PATIENT(S): A 27-year-old woman who was transferred to our hospital because of ovarian hyperstimulation syndrome. INTERVENTION(S): Induced abortion. MAIN OUTCOME MEASURE(S): Antithrombin III activity in plasma and ascites. RESULT(S): Antithrombin III activity in ascites was slightly lower than that in plasma. CONCLUSION(S): The loss of antithrombin III into ascites probably caused its deficiency in this case.

Adult↗