Biomedical subjects

N Hoshi

Publications and source records attributed to N Hoshi.

At least 19 recordsLinked to original sources

PubMed2000

Factor XII deficiency in women with recurrent miscarriage.

Congenital thrombophilia is known to cause significant maternal complications, and possibly has an adverse effect on normal fetal development. The aim of this study was to assess the prevalence of factor XII (FXII) deficiency in women with a history of recurrent miscarriage. Two hundred and forty-one consecutive Japanese women with a history of two or more recurrent miscarriages were prospectively assessed for their etiology by conventional screening methods. Seven women were found to have reduced FXII activity (19. 2-46.1%) and prolonged activated partial thromboplastin time (33. 3-51.3 s). Of these 7 women, 6 had experienced early pregnancy losses, while 1 woman had experienced repeated mid-trimester fetal losses with coincidental gestational thrombocytopenia. In 241 women with a history of recurrent miscarriage, the prevalence of FXII deficiency was 2.9%.

Abortion, Spontaneous↗

PubMed2000

Aneuploidy of sex chromosomes in basal cell carcinoma: its clonality and involvement in the development of carcinogenesis.

Although basal cell carcinoma (BCC) is a major skin cancer, the mechanism of carcinogenesis with regard to cytogenetic abnormalities has not been fully investigated. In the present study, we carried out cytogenetic analyses of 18 patients (9 male and 9 female) with BCC. Aneuploidy was seen by Q-banding method in more than half of the cases and was mostly loss of the sex chromosome. We also performed FISH to the interphase nuclei of various tissues and short-term cultured BCC cells. The frequency of sex chromosomal aneuploidy was significantly higher in all samples from BCC patients (peripheral blood lymphocytes, non-lesional tissues, BCC tumor tissues and cultured BCC cells) than in age-matched normal controls. In addition, we analyzed clonality of BCC tissues using a human androgen receptor gene assay and found uniparental pattern of inactive X-chromosomes. This indicates that BCC cells were monoclonal in origin and the development of BCC might be correlated with sex chromosomal aneuploidy, which acquired accumulation of genetic mutations.

Adult↗

PubMed1999

12-Lipoxygenase overexpression in rodent NG108-15 cells enhances membrane excitability by inhibiting M-type K+ channels.

1. 12-Lipoxygenase produces 12-hydroperoxy acid from arachidonic acid released from membrane phospholipids. To elucidate the role of the enzyme in neuronal functions, mouse neuroblastoma x rat glioma hybrid NG108-15 cells were permanently transfected with the cDNA for human 12-lipoxygenase. 2. The number of action potentials evoked by depolarizing current steps in a current-clamp mode was strikingly increased in 12-lipoxygenase-expressing NG108-15 cells as compared with the wild-type cells which hardly had the enzyme activity. 3. In the transformed cells, the M-type voltage-dependent K+ current was significantly reduced with little or no change in other ion channel currents. 4. Treatment of the transformed cells with a 12-lipoxygenase inhibitor recovered the action potential frequency and the M-current amplitude to the control level. 5. These results indicate that 12-lipoxygenase and/or its metabolites target K+ channels and upregulate the membrane excitability, and thereby modulate neuronal signalling.

Action Potentials↗

PubMed1999

Recent trends in the prevalence of Down syndrome in Japan, 1980-1997.

The aims of the present study were to determine recent trends in the prevalence of Down syndrome (DS) in Japan, and to determine whether recent changes in demographic and social habits and access to prenatal diagnosis have influenced the livebirth rates of DS. Livebirth statistics indicate that the birth rate in Japan has decreased for women in their 20s and has increased for those in their 30s and 40s. During an 18-year period between 1980 and 1997, 1,299 consecutive DS infants were born among a total of 2,232,694 births, a rate corresponding to approximately 10% of all births in Japan over the same period. The increasing risk of DS with advancing maternal age was confirmed. The overall prevalence was 5.82 DS births per 10,000 livebirths (8.3-9.7 per 10,000 after correction according to the estimated ascertainment ratio: 60-70%). The prevalence rate by year of child birth represents a statistically significant increase (P = 0.001). In conclusion, recent trends in the prevalence of DS in Japan from 1980 to 1997 failed to show a consistent tendency to decrease, probably because of the concomitant increase in pregnancy in advanced maternal age.

Birth Rate↗

PubMed1999

Membranocystic lesion in lumbar yellow ligament.

STUDY DESIGN: An examination of surgical cases of membranocystic lesions in the lumbar yellow ligament between the fourth and fifth lumbar vertebrae. OBJECTIVES: To report the incidence and pathogenesis of membranocystic lesions of the yellow ligament in surgical specimens. SUMMARY OF BACKGROUND DATA: The membranocystic lesion has been observed not only in membranous lipodystrophy, but also in other conditions. However, there has been no report concerning this lesion in the yellow ligament. METHODS: Forty-four yellow ligaments excised in surgery were histologically reviewed. In eight cases, S-100 expression was investigated. In two cases, ultrastructural findings were examined. RESULTS: Membranocystic lesions were present in 8 (18%) of the 44 cases. The cases with the lesions had undergone surgery for spondylolisthesis (4 cases), sequestration-type disc herniation (2 cases), postradiation status (1 case), and spinal stenosis (1 case). Histologically, in all 8 cases, fibrosis was present around the lesion. In 5 of the 8 cases, chondrocytes were observed adjacent to the lesion, and nuclei positive for S-100 protein were observed in 4 cases. Nuclei of chondrocytes adjacent to the lesion also were positive for S-100 protein. Ultrastructurally, irregularly shaped cystic spaces surrounded by an electron-dense membranous structure, which were identical to those of membranous lipodystrophy, were observed. CONCLUSIONS: These results suggest that degeneration of the chondrocytes has a causal relationship to the formation of membranocystic lesions in the yellow ligament.

Adolescent↗

PubMed1999

Induction of antenatal periventricular leukomalacia by hemorrhagic hypotension in the chronically instrumented fetal sheep.

OBJECTIVES: Our purpose was to determine whether systemic hypotension induced by rapid withdrawal of fetal blood would induce periventricular leukomalacia in the brain of premature fetal sheep. STUDY DESIGN: At 113 days' gestation, systemic hypotension (mean blood pressure <30 mm Hg) was induced by withdrawing approximately 35% of the fetoplacental blood volume in the hemorrhage group (n = 6), whereas in the control group (n = 4) isovolemic exchange transfusion was carried out. Six days after the insult, fetal brains were removed and processed for histologic analysis. RESULTS: Five of the 6 fetuses in the hemorrhage group exhibited periventricular white-matter lesions, consisting of nodular coagulation necrosis or diffuse axonal swellings or both. No abnormal findings other than these lesions were detected in the fetal brains in either experimental group. CONCLUSION: Hemorrhagic hypotension antenatally induced brain lesions similar to those of periventricular leukomalacia, suggesting that it is an essential element in the pathogenesis of periventricular leukomalacia in premature fetuses.

Animals↗

PubMed1999

Tubal pregnancy in a unicornuate uterus with rudimentary horn: a case report.

OBJECTIVE: To report a case of tubal pregnancy in a unicornuate uterus with rudimentary horn on the side of the rudiment and its pathology. DESIGN: Case report. SETTING: University hospital. PATIENT: An 18-year-old woman, primigravida, with tubal pregnancy. INTERVENTION(S): Systemic administration of methotrexate, salpingectomy by laparotomy, and laparoscopic surgery for resection of rudimentary horn. MAIN OUTCOME MEASURE(S): Emergent laparotomy revealed that the intraperitoneal hemorrhage was caused by the rupture of the tubal pregnancy on the same side as the rudimentary horn of the unicornuate uterus. A corpus luteum was found at the ipsilateral ovary of the rudimentary horn. RESULT(S): Image diagnosis and pathological examination of the rudimentary horn revealed that this uterine malformation was a unicornuate uterus with a noncommunicated, noncavitary rudimentary horn, corresponding to class IIc of the American Fertility Society classification of müllerian anomalies. CONCLUSION(S): This is the first report of a tubal pregnancy on the side of the noncommunicating rudimentary horn with the ipsilateral ovary carrying a corpus luteum in a unicornuate uterus.

Abortifacient Agents, Nonsteroidal↗

PubMed1999

h-Caldesmon in leiomyosarcoma and tumors with smooth muscle cell-like differentiation: its specific expression in the smooth muscle cell tumor.

h-Caldesmon (h-CD) is a protein combined with actin and tropomyosin that regulates cellular contraction. h-CD has been thought to be expressed exclusively in vascular and visceral smooth muscle cells (SMC). We examined h-CD expression immunohistochemically in tumors with SMC and SMC-like differentiation to clarify whether h-CD is specifically expressed in SMC tumors. The tumors examined in this study were six leiomyomas (LM), two angioleiomyomas (ALM), six leiomyosarcomas (LMS), eight rhabdomyosarcomas (RMS), eight malignant fibrous histiocytomas (MFH), four desmoids, three glomus tumors (GT), and two inflammatory myofibroblastic pseudotumors (IMP) of urinary bladder. We found that LM, ALM, LMS, and GT showed intense and extensive immunoreactivity for h-CD, whereas other tumors were completely negative for h-CD. In addition, h-CD was not present in the vascular pericytes and myofibroblasts, in contrast to actin. Although myoepithelial cells were immunopositive for h-CD, neoplastic myoepithelial cells of myoepithelial tumors and mixed tumors of the salivary gland and skin were all negative. These findings indicate that h-CD is a specific marker of both SMC and its neoplasms and that immunohistochemical detection of h-CD may facilitate the differential diagnosis between LMS and other tumors with SMC-like differentiation, including myofibroblastic tumors.

Adolescent↗

PubMed1999

BRCA1 mutation testing for Japanese patients with ovarian cancer in breast cancer screening.

From February 1996 to April 1998, 2967 women received screening for breast cancer in the gynecologic ambulatory practice of the Hokkaido University Hospital. In 116 Japanese women with epithelial ovarian cancer, mutation analysis of BRCA1 exon 11 in genomic DNA was performed by the stop codon (SC) assay and DNA sequence analysis. Clinicopathological factors were also investigated in these patients. The aim of this study was to examine the advantages of performing BRCA1 mutation testing for ovarian cancer patients during breast cancer screening. We achieved a high detection rate (6.0%) of patients with germline mutations in BRCA1. The high frequencies of breast ovarian cancer syndrome, serous adenocarcinoma, high histological grades, advanced FIGO stages, and breast cancer as double cancer were found to be characteristic of ovarian cancer with germline mutations in BRCA1. These characteristics may assist physicians in selecting BRCA1 mutation testing for ovarian cancer patients. The mean age at diagnosis of ovarian cancer was 51.0 and 51.2 years in the groups with and without mutation, respectively, and no difference was found in age at diagnosis. All of the nine living female mutation carriers were offered the options of increased surveillance or prophylactic surgery, and all chose the former. We have performed breast cancer screening and/or ovarian cancer screening every 6 months for these carriers. This may allow another advantage in establishing a relationship of mutual trust with a patient from a series of responsible follow-ups.

Adolescent↗

PubMed1999

Large bursa formation associated with osteochondroma of the scapula: a case report and review of the literature.

Bursitis or large bursa formation associated with osteochondroma has rarely been reported. A 33-year-old male presented with upper back pain, a rapidly developing mass beside the lateral border of his right scapula and snapping elicited by movement of the scapula. Plain radiograms and CT revealed osteochondroma on the ventral surface of the scapula without any unmineralized component and a huge cystic lesion around the osteochondroma. Aspiration of the cystic lesion showed the presence of sero-sanguineous fluid. MRI following the aspiration showed a thin cartilaginous cap with distinct outer margin and no soft tissue mass around the cap. Pathological examinations confirmed the diagnosis of osteochondroma with the large bursa formation. Clinical examination 19 months postoperatively showed an uneventful clinical course.

Adult↗

PubMed1999

Existence of human DAZLA protein in the cytoplasm of human oocytes.

The human deleted in azoospermia-like autosomal (DAZLA) gene is thought to be a candidate gene for azoospermia. cDNA encoding the C-terminal 94 amino acid residues of human DAZLA was used to express a bacterial fusion protein which was then used to raise polyclonal antibodies in rabbits. Immunohistochemical analyses with the human DAZLA antiserum showed that the DAZLA protein is expressed at a cytoplasmic location in female germ cells. Available evidence suggests that the DAZLA gene is a participant in human oogenesis.

Adolescent↗

PubMed1999

Prevention of lung metastasis by intra-tumoral injection of Cepharanthin and staphylococcal enterotoxin B in transplantable rat osteosarcoma.

The antitumor effect of intra-tumoral injection of Cepharanthin, a biscoclaurin alkaloid extracted from Stephania cephalanta Hayata, and staphylococcal enterotoxin B was evaluated using F344 male rats bearing transplantable rat osteosarcoma, S-SLM. A macroscopic lung metastatic nodule of tumor was transplanted into the subcutaneous back space, and 0.5 mg of Cepharanthin and 2 pg of staphylococcal enterotoxin B were injected into the tumor on days 12, 13 and 14. On day 28, all animals were killed with an overdose of pentobarbital sodium, and the transplanted tumors and lungs were examined. The wet weight of the lungs of the rats treated with Cepharanthin and staphylococcal enterotoxin B was significantly lower, and apoptosis in the lung metastatic nodules was significantly higher than that of the control or that of rats treated with only Cepharanthin or staphylococcal enterotoxin B. In the transplanted tumors, infiltration of TRAP (tartrate-resistant acid phosphatase)-positive multinucleated giant cells was prominent in the rats treated with Cepharanthin and staphylococcal enterotoxin B. These findings indicate that intra-tumoral injection of Cepharanthin and staphylococcal enterotoxin B induced infiltration of TRAP-positive multinucleated giant cells within the transplanted rat osteosarcoma, and reduced lung metastasis.

Acid Phosphatase↗

PubMed1999

Morphological aspects of ectopia cordis: four case reports and a review of the literature.

Ectopia cordis is a rare congenital anomaly. We present 4 cases of ectopia cordis, 1 of which is the first report of an affected fetus in a triplet pregnancy. The morphological relationship between the types of ectopia cordis and their outcomes were investigated in all 4 cases. In addition, the literature on ectopia cordis in Japan was reviewed and discussed.

Adult↗

PubMed1998

KCR1, a membrane protein that facilitates functional expression of non-inactivating K+ currents associates with rat EAG voltage-dependent K+ channels.

Cerebellar granule neurons possess a non-inactivating K+ current, which controls resting membrane potentials and modulates the firing rate by means of muscarinic agonists. kcr1 was cloned from the cerebellar cDNA library by suppression cloning. KCR1 is a novel protein with 12 putative transmembrane domains and enhances the functional expression of the cerebellar non-inactivating K+ current in Xenopus oocytes. KCR1 also accelerates the activation of rat EAG K+ channels expressed in Xenopus oocytes or in COS-7 cells. Far-Western blotting revealed that KCR1 and EAG proteins interacted with each other by means of their C-terminal regions. These results suggest that KCR1 is the regulatory component of non-inactivating K+ channels.

Amino Acid Sequence↗

PubMed1998

Cloning of PCPTP1-Ce encoding protein tyrosine phosphatase from the rat cerebellum and its restricted expression in Purkinje cells.

Recently, cDNAs encoding brain-specific transmembrane-type protein tyrosine phosphatases (PTPs) with single catalytic domain have been cloned. These include PC12-PTP, PCPTP1, PTPBR7, and PTP-SL, whose cytoplasmic domains had high similarity to STEP, a brain-specific nontransmembrane-type PTP. Based on the high similarity and expression pattern, PCPTP1 seems to be identical with PC12-PTP1 and to be the rat homologue of murine PTPBR7. Here, we report the molecular cloning and expression profile of PCPTP1-Ce, a variant of PCPTP1. Both PCPTP1 mRNA and PCPTP1-Ce mRNA seem to be derived from a single common region gene. Nucleotide and deduced amino acid sequence comparison between PCPTP1-Ce and PCPTP1 revealed that the predicted protein product of PCPTP1-Ce is identical with that translated from the third initiation methionine of the longest ORF of PCPTP1, and that these two clones differ in the 5'-untranslated sequences. Northern blot analyses with specific probes for PCPTP1 and PCPTP1-Ce confirmed our previous observation that PCPTP1-Ce mRNA was almost exclusively expressed in the cerebellum, whereas PCPTP1 was widely expressed in various brain regions dissected including cerebellum. In situ hybridization study demonstrated that PCPTP1-Ce mRNA was exclusively expressed in Purkinje cells of the cerebellum. In contrast, PCPTP1 mRNA was predominantly expressed in granule cells and less in Purkinje cells. Moreover, immunohistochemical analysis using an affinity-purified polyclonal antibody raised against the cytoplasmic region of PCPTP1/PCPTP1-Ce demonstrated that Purkinje cells were strongly immunostained, whereas granule cells were stained only faintly in the cerebellum. These observations clearly demonstrated that PCPTP1-Ce mRNA and its protein products are expressed in Purkinje cells and suggest that PCPTP1-Ce may play an important role in Purkinje cell function in the rat cerebellum.

Animals↗

PubMed1998

Endomorphins inhibit high-threshold Ca2+ channel currents in rodent NG108-15 cells overexpressing mu-opioid receptors.

1. Extracellular application of the novel brain peptides endomorphin 1 (EM1) and endomorphin 2 (EM2) inhibited high-threshold Ca2+ channel currents in NGMO-251 cells, a daughter clone of NG108-15 mouse neuroblastoma x rat glioma hybrid cells, in which mu-opioid receptors are overexpressed. 2. In contrast, EM1 and EM2 did not induce this inhibition in the parental NG108-15 cells that predominantly express endogenous delta-receptors. 3. The IC50 for EM1 and EM2 was 7.7 and 23.1 nM, respectively. 4. EM-induced Ca2+ channel current inhibition was blocked by treatment or pretreatment of the cells with 100 microM N-methylmaleimide or 100 ng ml-1 pertussis toxin. 5. These results show that a decrease in conductance of Ca2+ channels results following interaction of EMs with cloned mu-receptors, which couple via Gi/Go-type G proteins, and that EMs fulfill one of the necessary synaptic conditions for them to be identified as neurotransmitters.

Animals↗

PubMed1998

Prenatal identification of mos 45,X/46,X,+mar in a normal male baby by cytogenetic and molecular analysis.

We report a case of mos 45,X/46,X,+mar, diagnosed prenatally by amniocentesis, whose physical examination, including external and internal organs, along with serum testosterone values were normal five years after delivery. The mosaic karyotype was seen in 146 of 240 cells examined (amniotic fluid cells, 110/65; placental chorionic villi: 5/4; cord blood, 21/81; cultured skin fibroblasts, 10/90) from 386 metaphases, and the marker chromosome appeared as a small non-fluorescent acrocentric chromosome. All autosomes appeared normal, and no normal Y chromosome could be demonstrated. Analysis of 26 Y-chromosome loci by molecular techniques such as PCR, Southern analysis using multiple Y-specific DNA probes, and Hae III restriction endonuclease assessment of male-specific repeated DNA in the heterochromatic region of the Y chromosome, and fluorescence in situ hybridization (FISH), revealed the marker was derived from a Y chromosome including p terminal to q11.23, and paracentric inversion in the remaining Y long arm. The formation of testes can be considered as existence of SRY (sex-determining region of Y) as a testis-determining factor. The present report illustrates the importance of FISH and molecular techniques as a complement to cytogenetic methods for accurate identification and characterization of chromosome rearrangements in prenatal diagnosis.

Adult↗

PubMed1998

Hematopoietic cytokine levels and in vitro colony formation assay in fetal anemia.

Fetal anemia causes hydrops fetalis and fetal ascites/hydrothorax, and in severe cases the prognosis is poor. Little other than alloimmunity and viral infections are known as mechanisms causing fetal anemia. The aim of this study was to elucidate any pathogenesis in fetal anemia due to otherwise idiopathic etiology. The levels of three hematopoietic cytokines, IL-3, erythropoietin (EPO), and granulocyte colony-stimulating factor (G-CSF) were measured in blood samples obtained by cordocentesis from six fetuses with anemia (Hb <10.0 g/dl) and 34 fetuses without anemia. Cordocentesis was performed prior to the onset of labor or uterine contractions in all pregnant women. The concentration of IL-3 in fetuses with anemia [M+/-(SD), 8.3 (10.1) pg/ml] was significantly lower than that in fetuses without anemia [59.9 (71.0) pg/ml]. EPO and G-CSF levels were not different between the two groups. In addition, through in vitro colony formation assay, using blood stem cells from two fetuses with severe anemia and three fetuses without anemia, it was found that colony forming unit-erythroid, burst forming unit-erythroid and granulocyte macrophage-colony forming unit were significantly suppressed in blood stem cells from the two fetuses with severe anemia. Thus, the malfunction of differentiation and proliferation of blood stem cells and the decrease of hematopoietic cytokine levels in the fetal circulation may be responsible for the occurrence of fetal anemia.

Colony-Forming Units Assay↗