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Y Sagara

Publications and source records attributed to Y Sagara.

At least 181 records · Page 10Linked to original sources
PubMed1990

Structural and functional characterization of human aromatase P-450 gene.

The gene encoding aromatase P-450 (CYP XIX) has been isolated from two types of human genomic DNA libraries. It spans at least 70 kb and consists of 10 exons. The translational initiation site and the termination site are located in exon 2 and exon 10, respectively. The promoter region of the gene contains a TATA box, a CAAT box and two putative AP-1 binding sites beginning at -28, -83, -55 and -68 bp, respectively, from the transcriptional initiation site. In addition, a palindromic nucleotide sequence is observed between -209 and -196 and two types of repetitious hexanucleotide (consensus: AATGAA and CCATAAGG) are also present within the regions between -485 and -433 and between -358 and -331. Transient expression studies of chloramphenicol acetyltransferase constructs bearing various lengths of 5'-flanking region of the gene show that the region between -500 and -243 contains negative cis-acting element(s), whereas the region between -242 and -183 is required for efficient transcriptional activity. Northern blot analysis demonstrates that the expression of aromatose P-450 gene is remarkably stimulated by treatment of cells with 12-O-tetradecanoyl-phorbol 13-acetate. By chloramphenicol acetyltransferase assay the region up to nucleotide position -242 relative to the transcriptional initiation site is shown to participate in the transcriptional responsiveness to this phorbol ester.

Amino Acid Sequence↗
PubMed1990

Structural organization of the bovine adrenodoxin gene.

The gene structure of bovine adrenodoxin (Ad), a component of the steroid hydroxylating system in adrenal cortex mitochondria, was determined. This gene seems to be a single copy, but contains a pseudo exon in addition to the genuine gene region. The gene region for the active Ad is divided into 4 exons by 3 introns, and spans at least 27 kb. All the splice donor and acceptor sites follow the GT/AG rule. The transcription initiation site was determined by primer extension analysis, and putative TATA and GC boxes are present in the 5'-flanking region. A 12 base sequence, CCAGGGCCAGGG, is present 95 bases upstream from the transcription initiation site. A similar sequence was also found in the 5'-flanking regions of all genes for the steroid hydroxylating cytochromes P-450: P-450(SCC), P-450(11 beta), P-450(17 alpha), and P-450(C21), in the adrenal cortex. The consensus sequence for these five sequences is CGCAGGGCCATGGGA. The pseudo exon, exon 1', was present about 0.5 kb upstream from exon 1. It encodes the prepeptide region of the minor type Ad mRNA, but has a stop codon (TAA) in the frame. A TATA-box-like sequence and a CAAT-box-like sequence are also present in the 5'-flanking region of exon 1'. The GC content of exon 1 was over 80%, whereas for each of the other four exons, including exon 1', it was about 40%. Our observations suggest that exon 1, which encodes the prepeptide region of the major type Ad mRNA, has intruded into the region between exon 1' and exon 2.

Adrenodoxin↗
PubMed1990

[Study on serotonin metabolism in toxemia of pregnancy].

To evaluate the serotonin (5-HT) metabolism in toxemia of pregnancy, plasma free 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), tryptophan and platelet 5-HT content were determined by high performance liquid chromatography (HPLC) with electrochemical detection. The mean plasma free 5-HT concentrations in the severe preeclamptic group (S) and the mild preeclamptic group (M) were significantly higher than those in the normal group (N). A significant correlation was found between plasma free 5-HT values and Gestosis Index scores. However, there was no significant difference between plasma 5-HIAA level and platelet 5-HT content in the preeclamptic groups and the N. The mean plasma beta-thromboglobulin (beta-TG) concentrations in the preeclamptic groups were significantly higher than those in the N. The mean platelet counts in the S were significantly lower than those in the N. The mean plasma 5-HIAA/5-HT ratio in the preeclamptic groups were significantly lower than those in the N. In conclusion, it is suggested that the higher plasma free 5-HT level in the toxemia of pregnancy seems to be attributed to the excess release of 5-HT from platelets in addition to the lower monoamine oxidase activity.

Blood Platelets↗
PubMed1990

[Serotonin metabolism in normal pregnant women and fetus].

To evaluate serotonin (5-HT) metabolism in normal pregnant women and their fetuses, plasma free 5-HT, 5-hydroxyindoleacetic acid (5-HIAA). Tryptophan (TRP) and platelet free 5-HT content were determined by HPLC with electrochemical detection. Plasma free 5-HT and TRP concentrations and platelet 5-HT content in pregnant women did not change during pregnancy. In contrast, plasma free 5-HIAA increased after 30 weeks of gestation and reached its peak at 37 weeks. 5-HT, 5-HIAA and TRP concentrations in umbilical cord plasma were significantly higher than in maternal plasma. However, platelet 5-HT content in the fetus was significantly lower than in the mother. No significant correlation was found between 5-HT concentrations in maternal and cord plasma. However, a significant correlation was found between 5-HIAA, concentrations in maternal and cord plasma. The total 5-HT/TRP ratio in cord blood was significantly lower than in the maternal vein. The 5-HIAA/5-HT ratio in cord plasma was markedly higher than in maternal plasma. In conclusion, we demonstrated the patterns of plasma free 5-HT, 5-HIAA, TRP and platelet 5-HT concentrations in normal pregnant women and their fetuses. Furthermore, rapid 5-HT metabolism in the fetus was suggested.

Female↗
PubMed1990

[Correlation between slopes of pulmonary blood flow-driving pressure curve and routine pulmonary function].

In 91 preoperative cases of lung cancer, an attempt was made to correlate the slopes of pulmonary blood flow-driving pressure curve (delta DP/delta CI), as constructed from unilateral pulmonary arterial occlusion (UPAO) test values and pulmonary blood flow fraction values as measured by scintigraphy, with total pulmonary vascular resistance index (TPVRI) and pulmonary vascular resistance index (PVRI) and routine pulmonary function. FVC and FEV per unit body surface (BSA) were found to correlate, to same degree, with delta DP/delta CI, TPVRI and PVRI (p less than 0.05). delta DP/delta CI correlated significantly with FRC/BSA, whereas TPVRI and PVRI did not. 3) The inverse of the cardiac index (1/cardiac index) was shown to significantly correlate with TPVRI and PVRI (r = 0.64, 0.48), but poorly with delta DP/delta CI (r = 0.32). These results suggest that delta DP/delta CI might possibly provide a more useful quantitative index for the pulmonary vascular bed than TPVRI and PVRI.

Adult↗
PubMed1989

[Assay of activated form of progesterone receptor with ATP-sepharose column chromatography].

Biological actions of progesterone are correlated with the ability of the progesterone receptor(PR) to bind to nuclear acceptor sites. Measurement of not only the presence of PR in a tissue but also the amount of that receptor which is able to bind to nuclear acceptor sites is important in predicting tissue response to progesterone. Activation of PR is required for effective binding to chromatin. Since the dextrancoated charcoal assay does not distinguish between an activated and a non-activated receptor, a rapid, relatively simple assay is needed which can account for an activated form of PR. Therefore, ATP-Sepharose column chromatography was tested to identify an activated form of PR. PR in crude uterine cytosol from estrogen-primed immature rabbits was labeled with 3H-progesterone at 0 degree C. The labeled PR was then incubated at 4 degrees C with uterine chromatin from ovariectomized mature rabbits. The freshly prepared PR had little capacity to bind to the chromatin. After activation manipulation at low temperature, low ionic strength and neutral pH, this PR was able to bind to chromatin approximately fourfold more than that activated by heating at 25 degrees C. The affinity of the activated and the non-activated PR for ATP was evaluated on ATP-Sepharose column chromatography. The activated PR was selectively adsorbed onto columns of ATP-Sepharose, and the binding ability of the activated PR to ATP paralleled that of the rabbit uterine chromatin. These results suggest that ATP-Sepharose column chromatography could be useful to identify an activated PR as a substitute for chromatin binding assay.

Adenosine Triphosphate↗
PubMed1989

Alternative usage of different poly(A) addition signals for two major species of mRNA encoding human aromatase P-450.

Two cDNA clones for human placental aromatase P-450 (P-450AROM) have been isolated and sequenced. The insert of one clone (2894 bp) contains an open reading frame encoding a protein consisting of 503 amino acid residues together with a 49 bp 5'-untranslated stretch and a 1336 bp 3'-noncoding region to which a poly(A) tract is attached. Three potential poly(A) addition signals are detected in this 3'-noncoding region. The other clone contains a shorter cDNA insert, the nucleotide sequence of which overlaps with most of the sequence of the longer cDNA insert (nucleotides 36-2355) except for one nucleotide substitution. The 3'-noncoding region of this shorter cDNA is only 846 bp in length but a poly(A) tract is also attached to its 3'-terminus. Northern blot analysis of human placental RNA reveals the presence of two major mRNA species of 3.4 and 2.9 kb when probes excised from the overlapping region of these two cDNAs are employed. The 2.9 kb mRNA is not detected, however, when a fragment of the non-overlapping region of the longer cDNA is used as a probe. It is therefore concluded that the two major species of P-450AROM mRNA are formed as a consequence of alternative processing of precursor mRNA(s).

Amino Acid Sequence↗
PubMed1989

Immunocytochemical localization of adrenodoxin in bovine adrenal cortex by protein A-gold technique.

To investigate the intracellular localization of the enzymes that are involved in steroid hormone synthesis, an immunocytochemical study of the distribution of adrenodoxin in cells of the bovine adrenal cortex was carried out by the post-embedding immunostaining method and by immuno-cryoultramicrotomy in combination with the protein A-gold technique. Gold particles were seen on the matrix and the inner membrane of all the mitochondria examined, which have typical vesicular or tubulo-vesicular cristae, in parenchymal cells of the zona fasciculata and the zona reticularis. Gold particles were distributed homogeneously among the mitochondria. The density of gold particles on mitochondria in the parenchymal cells of the zona glomerulosa was lower than that of the zona fasciculata, which was similar to that of the zona reticularis. Gold particles were also seen on round, electron-dense intramitochondrial bodies in the parenchymal cells. The intramitochondrial bodies were abundant in the zona glomerulosa and the outer region of the zona fasciculata.

Adrenal Cortex↗
PubMed1989

A case of ovarian leiomyoma.

A case of ovarian leiomyoma is reported, together with histologic, immunohistologic and electron microscopic findings. A solid firm tumor, measuring 6.5 X 5 X 5 cm, was found in the right ovary of a 65-year-old woman. The tumor had an obvious whorled pattern on the cut-surface. Well-differentiated, long spindle-shaped neoplastic cells revealed positive immunoreactivity for anti-desmin. Ultrastructural observations included numerous microfilaments with dense patches in the cytoplasm, micropinocytotic vesicles beneath plasma membranes and continuous basal laminae around neoplastic cells. These findings were compatible with leiomyoma. The possible histogenesis of ovarian leiomyoma was discussed.

Actin Cytoskeleton↗
PubMed1989

[Respiratory regulations of pulmonary vagal nerves under hypercapnic conditions; effects of J-receptor].

We studied ventilatory responses under hypercapnic condition in 9 lightly anesthetized dogs, using a vagal nerve cooling technique. One side of the cervical vagosympathetic trunks of dogs were previously severed, and a copper cooler was attached to the other side. When the cervical nerve was cooled below 7 degrees C, the Hering-Breuer inflation reflex ceased. We found that when the vagal nerve was not cooled or cooled to 7 degrees C, the respiratory frequency increased significantly in relation to hypercapnic gas inhalation. However, the increment of respiratory frequency was reduced by bilateral cervical vagotomy. We concluded that the J-receptor is responsible for the increase in respiratory frequency under hypercapnic gas inhalation.

Animals↗
PubMed1989

[Pulmonary hemodynamics during mild exercise in COPD].

The effects of mild exercise on pulmonary hemodynamics and ventilatory responses in COPD were studied. Six patients with FEV1% less than 70% received 20 watt exercise tests by cycle ergometers for 5 minutes. Changes in hemodynamics and ventilation were observed before and during exercise. Nine patients with an FEV1% of more than 70% also received exercise tests as controls. There were no different in changes in respiratory frequency, tidal volume and minute ventilation between control and COPD group. However, the mean pulmonary arterial pressure were higher in the COPD group than in the control group before exercise. Moreover increments of mean pulmonary arterial pressure by exercise were also greater in COPD group. It was concluded that hemodynamics in COPD are much more influenced by mild exercise than in healthy subjects.

Adult↗
PubMed1989

[Pulmonary fibrosis after endotoxin-induced permeability edema].

To know the pathogenesis of the lung fibrosis after ARDS, we investigated the role of PMN-elastase after endotoxin-induced pulmonary edema in awake sheep with chronic lung lymph fistulas. The permeability of the pulmonary circulation increased 2 hours after endotoxin injection. Four hours after endotoxin injection, WBC migrated to the lung interstitium and the number of WBC in BALF increased. Endotoxin increased PMN-elastase in plasma and lymph whereas the level of alpha-1-protease inhibitor (alpha-1-PI) did not change. The activity of alpha-1-PI measured by trypsin inhibitory capacity was zero in the exudative phase. The level of PMN-elastase in lymph was significantly higher 1 week after endotoxin injection than baseline levels. Histologically, pulmonary fibrosis developed 1 week after endotoxin injection. These results suggest that inflammatory mediators released from PMN play an important part in progress to the fibrotic phase after ARDS.

Animals↗