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Biomedical subjects

N Harada

Publications and source records attributed to N Harada.

At least 325 records · Page 18Linked to original sources

Synthesis and biological activity of O-alkyl-3-N-aminoacyloxymethyl-5-fluoro-2'-deoxyuridine derivatives.

In an attempt to improve the effectiveness of action of 5-fluoro-2'-deoxyuridine (FUdR), various kinds of O-alkylated water-soluble analogues were synthesized. Antitumor activities against sarcoma 180 (solid) were also evaluated. Some compounds exhibited potent activities. In particular, 3'-O-p-chlorobenzyl-3-N-aminoacyloxy-methylester derivatives were effective over a very wide range of dose and gave extremely large therapeutic ratios compared with known 5-fluorouracil (5-FU) derivations.

Animals↗

Intraovarian immunolocalization of steroidogenic enzymes in a Hokkaido brown bear, Ursus arctos yesoensis during the mating season.

Immunolocalization for four steroidogenic enzymes was performed on an ovary taken from a Hokkaido brown bear during the mating season. This specimen is considered to be in the follicular phase because of the presence of large follicles. In large follicles, cholesterol side-chain cleavage (P450scc) and 3 beta-hydroxysteroid dehydrogenase (3 beta HSD) were immunolocalized in theca interna cells and granulosa cells. 17 alpha-hydroxylase/C17-C20 lyase cytochrome P450 (P450c 17) was immunolocalized in theca interna cells but not in granulosa cells. Aromatase cytochrome P450 (P450arom) was immunolocalized only in granulosa cells. In medium follicles, however, P450scc and 3 beta HSD were immunolocalized only in theca interna cells, and the immunoreactivity of P450arom was detected in neither theca interna cells nor granulosa cells. Immunoreactivities of P450scc, 3 beta HSD and P450c 17 but not P450arom were detected in interstitial cells. This study suggests that estrogen biosynthesis takes place through interrelation between theca cells and granulosa cells and is explained by the so-called two-cell mechanism. Furthermore, the granulosa cells in large follicles have the capability for pregnenolone and progesterone biosynthesis, and the interstitial cell in the bear ovary is also a steroidogenic site.

3-Hydroxysteroid Dehydrogenases↗

Incomplete testicular feminization syndrome: studies on androgen receptor(AR) function, AR gene analysis, and aromatase activities at puberty and long-term observations of clinical and hormonal features from infancy to puberty.

A female infant with partial androgen insensitivity (PAIS) was first seen at 4 months of age with slight virilization of the genitalia and externally palpable testes. Sex chromosome was 46,XY. She received left orchidectomy and exploratory laparotomy at 2 yr of age. At exploratory laparotomy, neither a uterus nor fallopian tubes were found. The right testis was preserved by fixing it at the external inguinal ring expecting spontaneous pubertal maturation. After discharge, serum levels of LH, FSH, testosterone (T) and estradiol (E2) were measured annually, and the steroid responses to hCG stimulation were examined every two yr. At the age of 10 yr, she developed breasts and a very feminine body habitus. At 12 yr, she received a clitoroplasty and right orchidectomy. The fibroblast cultures were made from the genital skin whereby androgen receptor (AR) binding was assessed by radioreceptor assay using 3H-DHT as the ligand, and thermoinstability of AR was noted despite normal maximum binding (Bmax) and dissociation constant (Kd) at 22 degrees C. But another binding experiment with 3H-Mibolerone resulted in the lack of receptor binding. AR gene analysis with direct sequencing of coding exons of the gene revealed no abnormality of the AR gene. 5 alpha-reductase activity was normal. Aromatase activity appeared to be enhanced in the genital skin fibroblast (GSF) cells as well as in the testicular tissue. The results of these studies indicated that the patient had PAIS with impaired AR functions and increased aromatase activity. After the discharge, the patient has maintained feminine phenotype, receiving estrogen therapy with mestranol 0.02 mg/day po.

Aging↗

Aromatase in human common epithelial ovarian neoplasms.

The expression of aromatase was evaluated in 44 ovarian carcinomas, 7 carcinomas of low malignant potential (LMP), and 14 benign adenomas. Aromatase immunoreactivity was observed in stromal cells in 35 of 44 (79.5%) ovarian carcinomas and 3 of 7 carcinomas of LMP. However, no immunoreactivity was pronounced at sites of frank invasion in ovarian carcinoma. To characterize aromatase in ovarian carcinoma, aromatase activity, mRNA expression, and alternative uses of exon 1 were determined. Quantitation of aromatase activity with the tritiated water method demonstrated 41.62 +/- 9.15 pmol/hour/mg protein in 11 ovarian carcinomas. The mean concentration of aromatase mRNA for 14 ovarian carcinomas was 3 +/- 4 amol/ng RNA, which significantly correlated with aromatase immunoreactivity. The alternative use of multiple copies of exon 1 was examined by reverse transcriptase polymerase chain reaction in 11 carcinomas. The transcript, mainly using exons 1c and 1d, was detected in 4 and 5 cases of carcinoma, respectively. Patterns of utilization of exon 1, however, did not significantly correlate with aromatase overexpression. These results suggest that aromatase is expressed in stromal cells of ovarian carcinoma but not in benign ovarian neoplasms. Increased aromatase expression in stromal cells of human ovarian carcinoma is, therefore, considered to play an important role in the biological behavior of these tumors by producing estrogens in situ as in other female sex-steroid-dependent neoplasms.

Adenocarcinoma↗

[The effect of work-related stress with change of working conditions for workers with alcohol drinking habit and liver disorder].

To evaluate the relationship between working conditions and workers' health, particularly the effect of work-related stress with change of working conditions for those with alcohol drinking habit and liver disorder, we analyzed physiological examination data and a questionnaire survey including the Japanese version of Karasek's Job Content Questionnaires (JCQ) on work-related stress, working hours, sleeping hours, alcohol consumption and cigarette smoking among male workers of a car manufacturing plant, who engaged in car sales work temporarily and then returned to manufacturing work. In the physiological examination data, the values of body mass index (BMI), GOT, GPT, gamma-GTP, TG and T-CHO rose and the prevalence of obesity and liver disorder increased during the term of car sales work. Comparing the term of car sales work with the term of car manufacturing work, the number of habitual drinkers and heavy smokers increased during the former and decreased during the latter. Increased alcohol consumption and cigarette smoking were also noted during the term of car sales work. Logistic regression analysis showed that the odds ratio of decreasing 'decision latitude (DL)' as work-related stress was statistically significant for increased alcohol consumption. The increased alcohol consumption probably contributing to the prevalence of liver disorder was assumed to be associated with work-related stress due to change of work conditions. Workers who showed liver disorder strongly complained of work-related stress, and it was assumed that the work-related stress was related to liver disorder. Longitudinal observations which take into account work-related stress, alcohol drinking habit and liver disorder must be well planned and personal traits of work-related stress always be taken into consideration.

Adult↗

[Rorschach response process in schizophrenia].

Although H. Rorschach considered the Rorschach test as a perceptual experiment, little research has been done on the experiment. Moreover, the Rorschach signs of perceptual impairment in schizophrenia, which he indicated and many scholars have supported, have never been examined by the perceptual experiments. The purpose of this study is to make clear the relationship between the Rorschach response and the perceptual process in schizophrenia by investigating cognitive activities using eye-mark recorder. Four Rorschach cards were selected, achromatic cards I and V, and chromatic cards II and VIII. Thirty chronic schizophrenic inpatients (who met DSM-III-R for "Residual Type", and whose negative symptoms were evaluated according to SANS) and 20 normals were all administered the Rorschach test in the used manner but they wore an eye-mark recorder. Their eye movements during reporting the initial response to each card were recorded on the VTR connected with the eye-mark recorder. On the response of each card, five eye movement items (1.total response time; 2.number of eye-fixation movements/sec.; 3.mean eye-fixation time; 4.mean eye-fixation tracking length, and 5.eye-fixation frequency on each detail area) were measured and analyzed. By their initial response, subjects were divided into 3 response groups: Popular response group, non-Popular response group and Rejection group. On the achromatic cards I and V, cognitive activities during delivering Popular response in schizophrenia were examined in comparing with those of normals. On the chromatic cards II and VIII, after the eye movements of Popular response group in schizophrenia were compared with those of Normals, scanning activities of the non-Popular group, the Rejection group and the Popular group were investigated in comparing with each other among schizophrenics. On the achromatic cards with the most solid blots; Cards I and V, the schizophrenics could easily give a Popular response the same as normals. However, the visual scanning activity of schizophrenics was limited on a small detail area and inactive compared with normals. The results show the discrepancy between the response and the cognitive activity. On the achromatic cards, this suggests that the Rorschach response process in schizophrenia is different from those of normal's, even if the responses of schizophrenia is the same as those of normals. On the chromatic cards with the most broken blots; Cards II and VIII, most of schizophrenics failed to give any response, hardly gave a Popular response but a non Popular response. Among schizophrenics, the few Popular groups indicated a limited pattern with poor scanning on the blot. Besides in SANS, their negative symptoms showed high attentional impairment. Although the non-Popular group gave many color responses, they avoided looking at the color areas, As for the Rejection group, although eye-fixation shifted and searched all over the blots, the subjects failed to give any response. Particularly on Card II, some of their visual focal points scattered on the white space areas out of the blot. This implies the failure of perception focusing on the appropriate blots as the relative stimulus. This implies the impairment of selective attention in schizophrenia. These results suggest that it didn't reveal in the usual manner of Rorschach test until the observation with eye-mark recorder made it possible to show us the response process in schizophrenia.

Adult↗

[Comparison between monotherapy with imipenem/cilastatin sodium (IPM/CS) and combinations of IPM/CS and other drugs for treating bacterial infections in patients with hematopoietic disorders].

One hundred and nine patients with infections concurrent with hematopoietic disorders were treated with imipenem/cilastatin sodium (IPM/CS) either alone (IPM/CS monotherapy) or in combination with other antimicrobial drugs (IPM/CS combination therapy). The following results were obtained. 1. One hundred and nine patients were allocated at random to two groups: 53 patients to IPM/CS monotherapy and 56 patients to IPM/CS combination therapy. Fourteen patients (6 and 8 in the 2 groups, respectively) were excluded from the clinical evaluation. There were not significant differences between the two groups with respect to the background. 2. The efficacy rates of the 2 treatments against bacterial infections were as follows: in the IPM/CS monotherapy group, 62.5% in 8 patients with sepsis, 75.0% in 23 patients with fever of undetermined origin (FUO), 50.0% in 10 patients with pneumonia, and 68.3% in the 47 patients, and in the IPM/CS combination group, 85.7% in 7 patients with sepsis, 63.6% in 24 patients with FUO, 50.5% in 8 patients with pneumonia, and 67.4% in the 48 patients. The differences between the two groups were not significant. 3. Among the drugs used in combination with IPM/CS, antibiotics other than penicillins, cephalosporins, and aminoglycosides were used in 12 patients and a high efficacy rate of 91.7% was obtained. 4. Bacteriologically, 19 and 17 strains were isolated from the IPM/CS monotherapy and combination therapy groups respectively, and the eradication rates were 100% and 88.9% respectively. 5. Side effects were noted in 2 patients in the IPM/CS monotherapy group and 7 in the combination therapy group, but all of these resolved after discontinuation or completion of the treatment. The efficacies against severe bacterial infections in the presence of hematopoietic disorders were not different between IPM/CS alone and IPM/CS in combination with other antibiotics. Adverse reactions were uncommon with the monotherapy.

Adolescent↗

[Empowerment in support groups for mothers with small children].

The purpose of this study was to describe the experiences of new mothers in peer support groups. The subjects were 14 mothers, each with children under 12 months of age. The mothers were members of one of three support groups either organized by public health nurses in a health center or midwives in two birthing centers. The data was collected through participant observations and interviews. Analysis of the data-the group experiences of mothers-allowed for categorization into three areas of support: 1) reassurance of oneself as a mother, 2) gaining power to form a relationship with the baby, and 3) reconstruction of one's own personal life. Results of the study showed that the support group was a source of empowerment for the new mothers. The elements of empowerment are indicated in the listed categories.

Adult↗

Bond strength to crown and root dentin.

PURPOSE: To investigate (1) the tensile bond strengths of four commercial dentin bonding systems to bovine crown and root dentin and (2) the structure of the hybrid layers for each system bonded to the two dentin substrates. MATERIALS AND METHODS: Superficial surfaces were exposed in bovine crown and root dentin. The teeth were embedded in plaster and a 3 mm diameter bonding area was demarcated. The four bonding systems used were All-Bond 2, Super-Bond D-Liner Plus, Clearfil Liner Bond II, and ProBond. Bonding procedures followed the manufacturers' instructions with the exception of Super-Bond D-Liner Plus where the primer was left in situ for 60 seconds. Tensile bond strengths were tested after 24-hour storage in 37 degrees C deionized water. Specimens were also prepared for SEM observation of the hybrid layer, after treatment with 10% phosphoric acid, and 10% phosphoric acid and 5% sodium hypochlorite. RESULTS: Statistically lower bond strengths to crown dentin when compared with root dentin were observed for All-Bond 2, whereas Liner Bond II showed the opposite (P < 0.01). Both ProBond and Super-Bond D-Liner Plus showed no statistical differences between crown and root dentin (P > 0.05). Hybrid layers could be observed for All-Bond 2, Liner Bond II and Super-Bond D-Liner Plus, with no apparent differences between the hybrid layers of crown and root dentin. In the case of ProBond, where the smear layer was not removed during the priming stage, it appeared that the primer had infiltrated and caused hybridization of the smear layer. The differences in bond strength were thought to be related to the different bonding mechanisms of each material, as well as possible variations in the crown and root dentin substrates.

Acid Etching, Dental↗

Pre- and post-translational regulation of aromatase by steroidal and non-steroidal aromatase inhibitors.

Treatment of castrated quail with testosterone (T) reliably activates male copulatory behavior and, at the same time, increases the aromatase activity (AA), the number of aromatase-immunoreactive (ARO-ir) cells and the concentration of aromatase mRNA as measured by RT-PCR in the brain. All these effects can be mimicked by estrogens. The behavioral effects of T can be blocked by a variety of aromatase inhibitors and, in parallel, the AA is strongly inhibited in the preoptic area (POA). We showed recently that the steroidal inhibitor, 4-OH-androstenedione (OHA) markedly decreases the immunostaining density of brain ARO-ir cells while the non-steroidal inhibitor, R76713 (racemic Vorozole; VOR) unexpectedly increased the density of this staining, despite the fact that the enzyme activity was completely inhibited. To generalize these findings and try to identify the underlying mechanism, we compared here the effects of two steroidal (OHA and androstatrienedione [ATD]) and two non-steroidal (VOR and Fadrozole [FAD]) aromatase inhibitors on the aromatase immunostaining and aromatase mRNA concentration in the brain of castrated quail concurrently treated with T. The 4 inhibitors significantly blocked the activation by T of male copulation. The two steroidal inhibitors decreased the immunostaining of brain ARO-ir cells but both VOR and FAD markedly enhanced the density of this staining. In parallel, OHA and ATD completely blocked the T-induced increase in aromatase mRNA concentration, while VOR and FAD had no effect on these RNA concentrations in the POA-anterior hypothalamus and they decreased them only slightly in the posterior hypothalamus. Taken together these results suggest that the inhibition of AA by ATD or OHA and the subsequent removal of locally produced estrogens blocks the synthesis of aromatase presumably at the transcriptional level. By contrast, the two non-steroidal inhibitors tested here block AA but in parallel increase the aromatase immunostaining. This effect does not result from an enhanced transcription and it is therefore speculated that these compounds increase either the translation of the aromatase mRNA or the half-life of the protein itself.

Animals↗

Regulation of placenta-specific expression of the aromatase cytochrome P-450 gene. Involvement of the trophoblast-specific element binding protein.

The aromatase (cytochrome P-450AROM) gene contains multiple untranslated exons I that are differentially transcribed in a tissue-specific manner. DNA sequences within the initial -301 upstream of placenta-specific exon I (exon Ia) are sufficient for placenta-specific expression of aromatase. In gel mobility shift assay, three separate domains in this region form specific binding complexes with proteins extracted from choriocarcinoma JEG-3 nuclei. A fragment containing these domains activates transcription driven by a heterologous promoter in a cell type-specific manner. Two of the binding domains that form major complexes in gel shift assay compete with each other and with a DNA fragment containing the trophoblast-specific element (TSE), which is derived from the enhancer region of the human chorionic gonadotropin alpha-subunit gene and is believed to confer placenta-specific expression of the gene. The core sequence RNCCTNNRG is sufficient for recognition of the TSE-binding protein, which is detected only in nuclear extracts prepared from placenta and choriocarcinoma. A mutation introduced in the distal TSE core in aromatase promoter resulted in marked reduction of transcriptional activity, although TSE region by itself did not show enhancer activity as that in human chorionic gonadotropin alpha-subunit gene.

Aromatase↗

Fluid flow and osmotic stress induce tyrosine phosphorylation of an endothelial cell 128 kDa surface glycoprotein.

To investigate the flow sensing and the early signaling events in vascular endothelial cells (ECs), we surveyed changes in phosphotyrosine levels of glycoproteins using immunoblot analyses. Cultured bovine arterial ECs were exposed to steady laminar flow by using a coneplate type flow apparatus and glycoprotein fractions were partially purified by lectin affinity column chromatography. A 128 kDa protein band in the Ricinus-communis-agglutinin-bound fraction showed a rapid and consistent augmentation of tyrosine phosphorylation by flow. Cell surface domain-restricted biotinylation revealed that the 128 kDa glycoprotein has extracellular domain(s). Tyrosine phosphorylation of the 128 kDa protein was also observed in ECs subjected to hyper- or hypo-osmotic shock but not in ECs stimulated by Ca2+ mobilizing agents.

Animals↗

Interleukin 2 and erythropoietin activate STAT5/MGF via distinct pathways.

Signal transducers and activators of transcription (STAT) proteins play an important role in cytokine signal transduction in conjunction with Janus kinases (JAKs). MGF/STAT5 is known as prolactin regulated STAT. Here we demonstrate that interleukin 2 (IL-2) as well as erythropoietin (EPO) stimulate STAT5 and induce tyrosine phosphorylation of STAT5. These IL-2- and EPO-induced STATs have an identical DNA binding specificity and immunoreactivity. We also show that IL-4 induces a DNA binding factor which possesses similar, but distinct, DNA binding specificity from that of STAT5 and is immunologically different from STAT5. Analysis of two EPO receptor (EPOR) transfected CTLL-2 cell lines discloses that IL-2 activates JAK1 and JAK3 as well as STAT5, while EPO stimulates STAT5 and JAK2 in EPO-responsive CTLL-2 cells (ERT/E2). On the contrary, EPO activates neither JAK2 nor STAT5 in other cell lines that failed to respond to EPO (ERT cells). EPOR and JAK2 associate with each other regardless of EPO presence in ERT/E2 cells, however, such an interaction is not present in ERT cells. Thus, EPOR and JAK2 association seems to be important for EPO responsiveness in CTLL-2 cells.

Animals↗

Stimulation of DNA replication by truncated Fos and Jun proteins in a cell-free extract of Xenopus eggs.

The effects of truncated Fos (residue 116-211) and/or Jun (residue 224-334) proteins on the DNA replication of plasmid with or without an AP-1 binding site were examined in a cell-free extract of Xenopus eggs. These truncated proteins, which are depleted of the domains necessary for transcriptional activation, stimulated semiconservative DNA replication only in combination and in the presence of plasmid with an AP-1 binding site. These results suggest that truncated Fos and Jun proteins act together to stimulate DNA replication and that activation depends on the presence of an AP-1 binding site in the Xenopus cell-free DNA replication system.

Animals↗

Co-localization of aromatase enzyme and estrogen receptor immunoreactivity in the preoptic area during reproductive aging.

Immunoreactive aromatase enzyme (AROM-IR) was studied in the preoptic and septal ares of the male Japanese quail brain relative to the age-related decline in endocrine and behavioral components of reproduction. Additional analyses were conducted to determine if the co-localization of AROM-IR and estrogen receptor immunoreactivity (ER-IR) in the medial preoptic area change during aging. Young, sexually active, male quail (6 months of age) were compared to aged sexually active or inactive, male quail (36 months of age). Testis size decreased in old, sexually inactive males, similar to our previous observations. The numbers of AROM-IR neurons in the medial preoptic area (POM) and the lateral septum (LS) decreased significantly with aging and sexual activity. The number of cells that co-localized both AROM-IR and ER-IR did not differ with age. As a consequence of the age-related change in AROM-IR cells, the relative percentage of dual labelled (AROM-IR and ER-IR) and single labelled cells (AROM-IR) increased in aged males. These data provide histochemical evidence that alterations in the aromatase enzyme system in the medial preoptic area may underlie behavioral and endocrine events associated with reproductive aging.

Aging↗

Interleukin-3, granulocyte-macrophage colony stimulating factor and interleukin-5 transduce signals through two STAT5 homologs.

Interleukin-3 (IL-3) is an important regulator of hemopoiesis and considerable effort has been directed towards the study of its mechanism of signal transduction. In this paper, we describe the first molecular identification of a STAT transcription factor that is activated by IL-3. STATs exist in a cytoplasmic, transcriptionally inactive form which, in response to extracellular signals, become tyrosine phosphorylated and translocate to the nucleus where they bind to specific DNA elements. Several of these DNA elements were found which bind proteins in an IL-3-responsive manner. Analysis of these bandshift complexes with available antibodies to the known STATs suggests that IL-3 activates the DNA-binding ability of STAT5, a protein which was originally characterized as a prolactin-responsive transcription factor in sheep. IL-5 and granulocyte-macrophage colony stimulating factor (GM-CSF), which share a common signaling receptor subunit with IL-3, also activate STAT5. Unexpectedly, two murine STAT5 homologs, 96% identical to each other at the amino acid level, were isolated and IL-3-dependent GAS binding could be reconstituted in COS cells transfected with IL-3 receptor and either STAT5 cDNA. In IL-3-dependent hemopoietic cells, both forms of STAT5 are expressed and activated in response to IL-3.

Amino Acid Sequence↗

Purification and characterization of a newly identified isoform of cytochrome P450 responsible for 3-hydroxylation of 2,5,2',5'-tetrachlorobiphenyl in hamster liver.

In the hamster liver, 2,5,2',5'-tetrachlorobiphenyl (TCB) is metabolized to 3-hydroxy- and 4-hydroxy-2,5,2',5'-TCB to a similar extent, and formation of the former metabolite is stimulated by phenobarbital pretreatment of the animals, while that of the latter metabolite is stimulated by 3-methylcholanthrene pretreatment. In the present study, we identified a new isoform (designated P450HPB-1) of cytochrome P450 which proved to be phenobarbital-inducible and responsible for 3-hydroxylation of this TCB isomer. This isoform was purified from liver microsomes of phenobarbital-treated hamsters and characterized. P450HPB-1 has a molecular mass of 50 kDa, determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the absorption maxima of the oxidized form at 417 nm and of the reduced CO-complex form at 450 nm. The sequence of 28 amino acids of P450HPB-1 at the amino-terminal has a 68% similarity with those of rat P450 2B1 and mouse P450 2b10, 57% similarity with that of guinea pig P450GP-1, and 54% similarity with that of guinea pig P450GP-1, and 54% similarity with those of rabbit P450 2B4 and dog P450 2B11. P450HPB-1 in the reconstituted system catalyzed the 3- but not 4-hydroxylation of 2,5,2',5'-TCB, at a rate of 19.0 pmol/min/nmol P450. The isoform also has high catalytic activity for 17-oxidation of testosterone but low activity for the N-demethylation of benzphetamine and 16 alpha- and 16 beta-hydroxylations of testosterone. In microsomal metabolism of 2,5,2',5'-TCB, rabbit antiserum against P450HPB-1 almost completely inhibited 3- but not 4-hydroxylation. Immunoblot analysis of hamster liver microsomes revealed that P450HPB-1 was constitutive and phenobarbital-inducible but was decreased by pretreatment with 3-methylcholanthrene or 3,4,5,3',4'-pentachlorobiphenyl. These results suggest that P450HPB-1 belongs in the P450 2B subfamily and apparently plays a major role in the 3-hydroxylation of 2,5,2',5'-TCB, in hamster liver.

Amino Acid Sequence↗