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Biomedical subjects

A Yajima

Publications and source records attributed to A Yajima.

At least 55 records · Page 3Linked to original sources
PubMed1999

Melatonin stimulates proliferation and type I collagen synthesis in human bone cells in vitro.

The pineal secretory product melatonin reportedly regulates release of growth hormone in humans and prevents phototherapy-induced hypocalcemia in newborn rats, suggesting that melatonin affects bone metabolism. Little is known about the effects of melatonin on bone in vitro or in vivo. The present study was undertaken to examine whether melatonin acts directly on normal human bone cells (HOB-M cells) and human osteoblastic cell line (SV-HFO cells) to affect osteogenic action in vitro. The effect of melatonin on bone cell proliferation was determined using the 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carbo xanilide (XTT) assay after a 24 hr incubation with melatonin. Melatonin significantly and dose-dependently increased the proliferation in HOB-M cells and SV-HFO cells by 215 +/- 22.1%, and 193 +/- 6.4%), respectively, with a maximal effect at a concentration of 50 microM. To evaluate the effect of melatonin on bone cell differentiation, alkaline phosphatase (ALP) activity, osteocalcin secretion and procollagen type I c-peptide (PICP) production (a measure of type I collagen synthesis) were measured after a 48 hr treatment. While melatonin at micromolar concentrations did not significantly affect either the ALP activity or the osteocalcin secretion, it significantly and dose-dependently increased the PICP production in HOB-M cells and SV-HFO cells by 983 +/- 42.2%, and 139 +/- 4.2%, respectively, with the maximal stimulatory doses between 50 and 100 microM. These results provide new evidence that melatonin stimulates the proliferation and type I collagen synthesis in human bone cells in vitro, suggesting that melatonin may act to stimulate bone formation.

Alkaline Phosphatase↗
PubMed1999

Transforming growth factor-beta isoforms and receptors in endometriotic cysts of the human ovary.

PROBLEM: The present study examined the presence and cellular distribution of transforming growth factor-beta1, 2, and 3 isoforms and their type I and II receptors in endometriotic cysts of the ovary, relative to their presence in normal endometrial tissue. METHOD OF STUDY: Thirteen control samples of normal endometrium in the proliferative phase and 11 ovarian endometriotic cysts were examined by immunohistochemistry for transforming growth factor-beta1, 2, and 3 isoforms and their type I and II receptors. RESULTS: Immunoreactivity for all ligands and receptors was detected in both normal endometrium and endometriotic cysts. Isoform-specific differences in immunostaining were not detected. Expression of all ligands and receptors was significantly increased in epithelial cells of endometriotic cysts compared with those of normal endometrium. On the other hand, stromal cells in normal endometrium and endometriotic cysts were only faintly immunostained. Inflammatory cells infiltrating among endometriotic stromal cells contained the highest immunostaining intensity for all ligands and receptors. We identified nearly all inflammatory cells as macrophages using a specific antibody. CONCLUSIONS: These findings suggest that macrophages in endometriotic tissue are a major source of transforming growth factor-beta, which may be an important regulator of cell proliferation in endometriotic cysts through paracrine and autocrine actions.

Activin Receptors, Type I↗
PubMed1999

Intercellular adhesion molecule-1 and hepatocyte growth factor in human endometriosis: original investigation and a review of literature.

Defects in the cell-mediated immune system may play a role in the pathogenesis or progression of pelvic endometriosis. Possible mediators include macrophages, interleukins-1 and -6, and tumor necrosis factor-alpha. More recent work points to the involvement of adhesion molecules and growth factors. To clarify the pathogenesis of endometriosis, we compared the characteristics of soluble intercellular adhesion molecule-1 (soluble ICAM-1) and hepatocyte growth factor (HGF) in women with and without endometriosis. We found that, in patients with endometriosis, the concentrations of soluble ICAM-1 in peritoneal fluid increased and interfered with the activity of natural killer cells. We also found that HGF secretion was significantly increased in cultured endometrial stromal cells, and that HGF stimulated the proliferation and migration of, and morphogenic changes in, endometrial epithelial cells. HGF and ICAM-1 play important roles in the initiation and regulation of endometriotic lesions on the microenvironment level. The increased secretion of HGF by eutopic endometrial stromal cells may contribute to the pathogenesis of endometriosis, whereas the increased levels of soluble ICAM-1 may impair natural killer cell activity and accelerate the progression of the disease.

Cell Division↗
PubMed1999

Apoptosis of human endometrium mediated by perforin and granzyme B of NK cells and cytotoxic T lymphocytes.

Endometrial stromal granulocytes (EGs) were found to be a major component of human endometrial stroma in the late secretory phase. However, the role of EGs in the mechanism of human endometrial menstruation has not been clarified. Immunohistochemistry of CD56, perforin, granzyme B, and vimentin, in situ detection of apoptosis by TUNEL (TdT-mediated dUTP-biotin nick and labeling) and electron microscopy were performed in endometrial tissue samples with normal menstrual cycles. We analyzed the number of immunostained cells in the functional layer of stroma and the number of apoptotic cells detected by TUNEL in the endometrial glandular cells. Double-staining revealed that CD56-positive endometrial stromal cells were simultaneously positive for both perforin and granzyme B, and negative for vimentin, which recognized stromal tissue. Vimentin was positive for the predecidual cells and negative for EGs. CD56-positive EGs involving perforin and granzyme B were progressively recruited during the secretory phases before menstruation. Apoptosis in endometrial glandular cells increased from the late secretory phase, which maximized at the menstrual period. This finding suggests that the cytotoxic granules released from EGs, which are derived from cytotoxic T lymphocytes and natural killer cells, are initiators of the apoptotic pathway that induces endometrial menstruation.

Adult↗
PubMed1999

Point mutations in the steroid-binding domain of the androgen receptor gene of five Japanese patients with androgen insensitivity syndrome.

We analyzed the androgen receptor (AR) gene in five Japanese patients diagnosed with androgen insensitivity syndrome (AIS). All AR genes from the five patients had single-nucleotide substitutions, which introduced a premature termination codon in three patients (Gln640, Arg752, and Gln640 and Trp751), and a single amino acid substitution in two patients (Arg831 to Gln, and Leu812 to Phe). All the mutations occurred in the steroid-binding domain, comprising exons D through G. The three patients with the premature termination codon(s) and the one patient with Arg831Gln were clinically diagnosed as having complete AIS, while the patient with Leu812Phe had a partial form of AIS. Pubic skin fibroblasts from four of the five patients did not show detectable androgen binding. These data on mutations that have not been reported previously, provide valuable information for the further characterization of structural and functional relationships in the steroid-binding domain of the AR protein.

Adult↗
PubMed1999

Conization of the cervix using harmonic scalpel.

Conization, as a surgical treatment for cervical intraepithelial neoplasm (CIN), is a good method that preserves reproductive functions. Technological developments have introduced a wide variety of energy sources for surgical procedures. Traditional cold knife conization has been replaced by laser conization and by the loop electrosurgical excisional procedure (LEEP). However, laser conization and LEEP have some disadvantages. Laser conization requires expensive equipment. LEEP induces electrocautery artifacts and cannot excise the cervical tissue as a single-piece, because of the various extensions and depths of lesion, so that evaluation of the margins is sometimes not possible. Laser conization and LEEP both generate smoke. The presence of smoke is not only inconvenient, but also dangerous. Harmonic Scalpel (HS), ultrasonic cutting and coagulation system, is a new surgical tool that cuts and coagulates using ultrasonic mechanical vibrations. Eleven women with CIN III underwent conization using HS. HS eliminated the major disadvantages of electrosurgery and laser surgery. No complications during conization were observed. Postoperative hemorrhage was noted in only one patient. Histological diagnosis was not affected by heat or ultrasound. This surgical method using HS is characterized by negligible bleeding, a good visual field not obscured by smoke and resection of an ideal shape that fits the size of the lesion. It is concluded that this method overcomes most problems associated with conization using conventional methods.

Adult↗
PubMed1999

K-ras point mutations in spontaneously occurring endometrial adenocarcinomas in the Donryu rat.

The Donryu rat has been found to have a high incidence of spontaneous uterine endometrial carcinomas. Moreover the histologic findings, biological nature and pathogenesis of these rat tumors appear similar to those in humans. To determine if the incidence of H- and K-ras gene mutations in these rat tumors is similar to that in human endometrial cancers, we isolated DNA samples from 2 atypical hyperplasias, 5 simple or complex hyperplasia without atypia, 9 adenocarcinomas and 7 histologically normal tissues, amplified exons 1 and 2 of the H- and K-ras genes by PCR and hybridized the products with allele specific oligonucleotide probes. K-ras point mutations were observed in 1/2 of the atypical hyperplasia (codon 12: GGT-->GTT) and 3/9 of the carcinoma (codon 12: GGT-->GAT, GGT-->AGT, codon 61: CAA-->CAC), while they were not detected in 7 of the normal tissues and in 5 of the simple or complex hyperplasia without atypia. H-ras point mutations were not detected in any of these DNA samples. These frequencies in this rat model are similar to those in humans. The absence of K-ras mutations from simple and complex hyperplasia tissue samples suggests that these mutations are associated with cytological atypia. Our findings suggest that alterations in the K-ras gene may be one of the important initiating event in endometrial carcinogenesis in some of the Donryu rat, like the human.

Adenocarcinoma↗
PubMed1999

Effects of aromatase inhibitors on the pathobiology of the human breast, endometrial and ovarian carcinoma.

It is very important to examine the influence of inhibition of in situ estrogen production on the pathobiology of human sex steroid-dependent tumors in order to understand the clinical effects of aromatase inhibitors. We have examined the biological changes before and after aromatase inhibitor treatment in vitro (endometrial and ovarian cancer) and in vivo (breast cancer). First, we analyzed these changes using histoculture of 15 human endometrial cancers and 9 ovarian cancers. Five of the fifteen endometrial cancers and four of the nine ovarian cancers demonstrated decreased [3H]thymidine uptake or Ki67 labeling index after 14alpha-hydroxy-4-androstene-3,6,17-trione (NKS01) treatment. In ovarian cancer cases, the responsive cases tended to be associated with higher aromatase and estrogen receptor alpha (ER) expression compared with the other cases but this was not seen in the endometrial cancer cases. There were no changes in ER and aromatase expression before and after NKS01 treatment in either ovarian or endometrial cancer cases. We then studied the same primary human breast tumors before and after aminoglutethimide (AMG, n=3) and 4-hydroxyandrostenedione (4-OHA, n=3) treatment. Tumor aromatase activity increased in 3 cases and decreased or was unchanged in 3 cases but aromatase immunoreactivity in stroma and adipocytes was unaltered in 5 cases. There were no changes in the ER labeling index before or after treatment. Five of the six cases including the responsive cases tended to be associated with decreased cell proliferation or Ki67 expression and increased apoptosis when examined by the TUNEL method. These results indicate that aromatase inhibitors may exert their effects on human breast and other cancers through decreasing proliferation and increasing apoptosis, possibly without altering ER status.

Antineoplastic Agents↗
PubMed1999

Adenovirus-mediated delivery of the PTEN gene inhibits cell growth by induction of apoptosis in endometrial cancer.

PTEN, a gene encoding a dual specificity phosphatase, is frequently altered in endometrial carcinoma. Moreover, these alterations are observed even in atypical hyperplasia of the endometrium. This evidence suggests that mutation of PTEN is an early genetic alteration involved in endometrial carcinogenesis. Adenovirus-mediated gene transfer was carried out using Ishikawa 3 H 12 and RL95-2, the endometrial cancer cell lines with completely inactivated PTEN, together with endometrial cancer cell lines HEC1-A and KLE expressing wild-type PTEN as the control. The PTEN transgene significantly suppressed cell growth in vitro through induction of apoptosis in cells lacking wild-type PTEN. Furthermore, the ex vivo tumor formation by Ishikawa 3 H 12 cells was completely inhibited by the introduction of wild-type PTEN. However, neither regression nor progression was observed in inoculated tumors of either cell line by in vivo introduction of the PTEN gene. These results suggest that PTEN may be a good candidate for gene therapy in patients with endometrial carcinoma.

Adenoviridae↗
PubMed1999

Laparoscopic cornuostomy for interstitial pregnancy. A case report.

BACKGROUND: With recent advances in laparoscopic surgery, many reports have described laparoscopic cornual resection for interstitial pregnancy as a safe alternative to laparotomy. We report a laparoscopic cornuostomy for unruptured interstitial pregnancy with myometrium reconstruction. CASE: A 32-year-old woman presented with complaints of abdominal cramps and vaginal spotting after 6 weeks of amenorrhea. Ultrasonographic examination revealed a gestational sac 7 mm in diameter in the left uterine corner. There was clear separation between the endometrium and gestational sac. A 3-mm periumbilical trocar for the laparoscope and a 3-mm trocar in the lower abdomen were used, and the left interstitial pregnancy was confirmed. An additional, 5-mm trocar was used in the lower abdomen for the laparoscopic surgery. The patient underwent a laparoscopic cornuostomy. Myometrium reconstruction was performed by suturing and tying with a laparoscopic technique. CONCLUSION: In this case, minilaparoscopy was useful in the diagnosis and treatment of interstitial pregnancy.

Abdominal Pain↗
PubMed1998

Tumor angiogenesis, hepatocyte growth factor, and c-Met expression in endometrial carcinoma.

BACKGROUND: This study was designed to evaluate the significance of tumor angiogenesis and angiogenic factors such as hepatocyte growth factor (HGF) and c-Met in determining the prognoses of 93 patients with endometrial carcinoma. METHODS: By immunohistochemical staining, this retrospective study investigated tumor angiogenesis, HGF expression, and c-Met expression, using one tissue slide that was representative of the invasive edge of the tumor. To evaluate tumor angiogenesis, the microvessels within the primary endometrial carcinoma were highlighted by staining their endothelial cells immunohistochemically for von Willebrand factor (VWF). The microvessels were then counted in the most intense areas of neovascularization. HGF and c-Met were identified with specific antibodies. Tumor angiogenesis, HGF expression, and c-Met expression were correlated with both the prognostic variables for and the survival of endometrial carcinoma. RESULTS: A high microvessel count (> or = 110 in a 0.90 mm2 area) was significantly correlated with surgical Stage III and IV, histologic Grade 3, positive lymph node involvement, and shorter patient survival. Expression of c-Met was significantly correlated with surgical Stage III and IV, histologic Grade 3, and shorter survival. HGF expression was significantly correlated with surgical Stage III and IV by semiquantitative analysis. Multivariate analysis showed that surgical Stage III and IV, histologic Grade 3, the score for myometrial invasion > 1/2, and a high microvessel count were independent indicators of the prognoses of patients with endometrial carcinoma. CONCLUSIONS: Both tumor angiogenesis, measured by the microvessel count, and c-Met expression were significant prognostic indicators for patients with endometrial carcinoma.

Adenocarcinoma↗
PubMed1998

Identification of a 100-kb region of common allelic loss on chromosome bands 10q25-q26 in human endometrial cancer.

In human endometrial cancer, we have previously identified a 790-kb region of common allelic loss in chromosome bands 10q25-q26, flanked by D10S587 and D10S1723. We constructed a contig covering the entire deleted region using YACs, PACs, and BACs. Five overlapping cosmid clones derived from YAC clones completely covered the entire deleted region: its size was estimated to be no larger than 200 kb. We further performed two-color fluorescence in situ hybridization (FISH) analysis to confirm the deletion and narrowed down the deleted region to 100 kb or less; it was covered by three overlapping cosmid clones that were included in one BAC clone. Restriction endonuclease mapping identified a region in which NotI, SalI, SmaI, and Xhol were clustered, suggesting the possible existence of a CpG island.

Chromosome Banding↗
PubMed1998

Incidence of ovarian cancer in women with prior hysterectomy in Japan.

OBJECTIVE: Our aim was to estimate the number of women in Japan in whom ovarian cancer could be prevented by performing prophylactic oophorectomy. METHODS: Of 1289 women who were diagnosed clinically and histologically as having primary cancers of the ovary between 1986 and 1995, 53 (4.1%) had undergone hysterectomy with conservation of one or both ovaries. Clinical data and representative microscopic slides for these 53 cases were evaluated. RESULTS: Hysterectomy had been performed at the age 45 or above in 28 of the 53 patients (53%). We estimated that performance of prophylactic oophorectomy in women who underwent a hysterectomy at age 45 or older would prevent 2.2% (4.1% x 0.53) of the cases of ovarian cancer in Japan, which is below the 3.3% estimated for women in other countries. The interval between the hysterectomy and the diagnosis of ovarian cancer ranged from 1 to 29 years (mean 9.9 years). Fourteen patients (26%) developed ovarian cancer within 5 years of the hysterectomy. The overall 3-year survival rate of these 53 patients was 65%, not significantly different from that for patients with ovarian cancer in the national study in Japan. CONCLUSIONS: Prophylactic oophorectomy for the prevention of ovarian cancer in Japanese women would appear to have a lesser impact than reported in other industrialized nations. The short interval between hysterectomy and the diagnosis of ovarian cancer observed in 26% of the patients suggested that ovarian cancer can develop within a few years of the visualization of apparently normal ovaries.

Adult↗
PubMed1998

Age-specific incidences of chromosome abnormalities at the second trimester amniocentesis for Japanese mothers aged 35 and older: collaborative study of 5484 cases.

The aim of this study was to calculate the expected incidences of chromosome abnormalities found at amniocentesis in Japanese women aged 35 and older. From four clinics in Japan, we gathered genetic amniocentesis data on 5484 pregnant women at risk only due to their advanced age, 35 years and older. We analyzed the data using the logistic regression model. Of the 5484 fetuses, 117 (2.1%) were diagnosed with a chromosome abnormality. The abnormal karyotypes included 42 cases of trisomy 21; 13 of trisomy 18; 7 of trisomy 13; 10 of 47,XXY; 4 of 47,XXX; 1 of 47,XYY; 27 with various structural aberrations; and 13 with various types of mosaicism. The incidences of trisomy 21, lethal autosomal aneuploidies (trisomy 18 and trisomy 13), and sex-chromosome abnormalities (XXY, XXX, XYY) increased with maternal age. Parameters of the regression equations with their standard errors were calculated and the expected incidences of chromosome abnormalities at each maternal age were derived. The expected incidences of chromosome abnormalities obtained in this study are the first data published for Japan and will be useful for the counseling of pregnant women. The incidence of trisomy 21 is not different from the rates published previously for Western countries. The incidences of chromosome abnormalities are not affected by race or by geographic factors.

Age Factors↗
PubMed1998

The incidence of, and factors leading to, parvovirus B19-related hydrops fetalis following maternal infection; report of 10 cases and meta-analysis.

OBJECTIVES: to clarify the approximation of the frequency of B19-related nonimmune hydrops fetalis (NIHF), and to know the critical period during which maternal infection led to NIHF. METHODS: we investigated the characteristics of 10 cases of antenatal B19 infection diagnosed over the past 10 years in Miyagi prefecture, Japan, and performed a meta-analysis of these cases and those previously reported in the literature. RESULTS: NIHF caused by intrauterine B19 infection was diagnosed between 11 and 23 weeks of gestation in 10 women over the past 10 years in Miyagi prefecture, Japan. The source of infection was the mother's older child in six out of 10 cases, and children at a kindergarten where the mothers worked in two cases. The interval between the onset of infection and the diagnosis of NIHF ranged from 2 to 6 weeks. B19 infection was responsible for 10 (15.2%) in 66 cases of aetiology unknown NIHF in this study, and for 57 (19.1%) of 299 cases of non-malformed or aetiology-unknown NIHF by meta-analysis of the literature. Meta-analysis of the 165 reported cases of antenatal B19 infection, including the 10 cases described above, showed that there was a 10.2% excess risk of fetal death in women infected with B19 during pregnancy and a 12.40% excess risk in women infected during the first 20 weeks of pregnancy. Transplacental transmission was confirmed in 69 (24.1%) of 286 cases. The mean gestational age at diagnosis of NIHF was 22.8 +/- 5.1 weeks. The mean interval between the onset of maternal infection and diagnosis of NIHF was 6.2 +/- 3.7 weeks. CONCLUSIONS: these approximations will be useful for counselling and management for pregnant women. The critical period during which maternal infection led to NIHF correlated with the hepatic period of hematopoietic activity. These findings suggest that parvovirus B19 may have an affinity for erythroid lineage cells at the hepatic stage of hematopoiesis, which may strongly influence the clinical features of feto-maternal B19 infection.

Female↗
PubMed1998

High dose intravenous immunoglobulin in atopic dermatitis and hyper-IgE syndrome.

BACKGROUND: High dose intravenous immunoglobulin (IVIG) has immunoregulatory and anti-inflammatory properties that might benefit illnesses with exaggerated IgE responses including atopic dermatitis and hyper-IgE immunodeficiency syndrome. OBJECTIVE: To determine if high-dose IVIG would be of benefit to patients with severe atopic dermatitis and/or hyper-IgE syndrome using serial clinical, pulmonary, and laboratory studies for evaluation. METHODS: This was an open label study in which we gave patients with hyper-IgE syndrome (n = 1) or severe atopic dermatitis (n = 9) IVIG as a 10% solution (Venoglobulin I-Alpha Therapeutic Corporation, Los Angeles, CA) at a dose of 2 g/kg every 30 days for seven infusions. RESULTS: Therapy was completed in nine of the ten patients. Skin disease improved slightly in six patients, remained unchanged in two patients, and worsened slightly in one patient. The average daily prednisone dosage was 6.8 mg/day prior to treatment and 5.1 mg/day during IVIG therapy (P = .1250). The three patients with abnormal pulmonary function showed very mild improvement of pulmonary function during treatment, but returned to baseline during follow-up. Flow cytometric studies showed no consistent pattern of change. IgA and IgM levels were unchanged. The mean serum IgE levels went from 3221+/-2454 IU/mL (SD) before IVIG to 2944+/-2491 IU/mL (P = .4609) during IVIG and then to 2321+/-2229 IU/mL (P = .1484) during the 6-month follow-up period. In vitro IgE production of peripheral blood mononuclear cells (PBMC) following IL-4 and anti-CD40 stimulation before IVIG was 6.6+/-3.1 ng/mL (SD) and 4.3+/-3.1 ng/mL (P = .1641) after six IVIG treatments. There were no significant trends in lymphocyte proliferative responses to PHA (phytohemaglutinin), Candida, tetanus, and anti-CD3 monoclonal antibody. Radioallergosorbent (RAST) testing showed no clear changes from positivity to negativity. CONCLUSION: We conclude that IVIG was of no clear clinical benefit in these nine patients and did not significantly decrease IgE levels, IgE synthesis, or other measures of immunologic function.

Adolescent↗
PubMed1998

Cyclic changes of vasculature and vascular phenotypes in normal human ovaries.

In order to study alterations of angiogenesis and blood vessel regression through ovarian cycle in human ovaries we quantitatively examined vascularity in various stages in 24 normal human ovaries. Vascular density (VD; vessel numbers/10(-7) m2) and endothelial area of each vessel (EA; 10(-12) m2/vessel) were evaluated using immunohistochemistry of CD34 and CAS 200 image analysis system. Small-sized vessels were sporadically observed in stroma adjacent to primordial or primary follicles (6.73 +/- 1.83 for VD and 113.58 +/- 21.80 for EA). Formation of capillary network was observed in the theca layer of preantral follicles (PA; 15.28 +/- 2.77 for VD and 113.58 +/- 21.80 for EA), and higher density of the capillary network was detected in non-dominant follicles in follicular phase (ND-F) and dominant follicles (DF; 29.33 +/- 3.84 for VD and 179.69 +/- 41.25 for EA). Dense capillary network was still present in non-dominant follicles in luteal phase (ND-L) and atretic follicles (AF; 26.88 +/- 3.36 for VD and 110.88 +/- 50.53 for EA). After ovulation, developing capillaries were also observed in the luteinized granulosa layers in early corpus luteum (21.95 +/- 2.06 for VD and 167.08 +/- 29.59 for EA). Vessel density markedly increased in mid corpus luteum, reached plateau in late corpus luteum (60.85 +/- 5.92 for VD and 70.99 +/- 15.57 for EA) and remained constant during degenerating corpora lutea. Vascular endothelial growth factor was immunohistochemically observed in the theca cells in PA, ND-F, DF and ND-L in follicular stages, and functioning corpora lutea. Immunoreactivity of intercellular adhesion molecule-1 was detected only in post-capillary venules in early degenerating corpora lutea. These findings suggest that ovarian angiogenesis is a requirement for the early stages of folliculogenesis and luteal growth, and also plays an important role in the process of follicular atresia and luteal regression.

Actins↗