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Biomedical subjects

K Kurachi

Publications and source records attributed to K Kurachi.

At least 91 records · Page 5Linked to original sources

Antitumor activity of a highly branched (1----3)-beta-D-glucan, SSG, obtained from Sclerotinia sclerotiorum IFO 9395.

The antitumor activity of a highly branched (1----3)-beta-D-glucan, SSG, purified from the liquid culture filtrate of Sclerotinia sclerotiorum IFO 9395 and its several derivatives were treated in ICR mice bearing Sarcoma 180 cells. SSG was effective by both systemic (intraperitoneal and intravenous) and local (intratumoral) administrations on the solid form of Sarcoma 180 in ICR mice and the mice acquired resistance to subsequent inoculation of Sarcoma 180. However, SSG was not effective on the ascites form Sarcoma 180. The pretreatment of ICR mice with carrageenan suppressed the antitumor activity, suggesting the involvement of macrophages on the antitumor activity. Derivatives prepared from SSG by periodate oxidation/borohydride reduction showed antitumor activity, but those obtained after acetylation, carboxymethylation and hydroxyethylation were less active. From these results, it is suggested that SSG is a useful antitumor glucan which modifies biological responses and can be used as a source for some antitumor derivatives.

Acetylation↗

Possible absence of common polymorphisms in coagulation factor IX gene in Japanese subjects.

Four distinct intragenic polymorphisms in the coagulation factor IX gene which have been reported to be important for family diagnosis of Caucasian hemophilia B were studied in 51 normal Japanese subjects (21 males and 30 females). High-molecular-weight DNA prepared from peripheral blood lymphocytes were digested with endonuclease, Ddel, Mspl, Taql or Xmnl, and were studied by Southern blot analysis with factor IX complementary DNA as a probe. None of the minor fragments produced by these enzymes was found in the normal Japanese DNA samples tested, although the probe detects minor allelic forms in control Caucasian DNA samples. Our data suggest that the frequent polymorphic sites found in Caucasians are possibly absent in the Japanese population.

Asian People↗

[Clinical significance of sialic acid determinations in patients with gynecologic cancer].

Sialic acid (SA) levels were measured in human sera by the enzymatic procedure using neuraminidase. Sera were obtained from healthy controls (70 females), patients with uterine myoma (27 cases), cervical cancer (53 cases), benign ovarian tumor (36 cases) and ovarian cancer (70 cases). The upper normal limit of 72mg/dl was obtained from the mean +2SD for healthy controls. The mean value for serum SA in patients with primary ovarian cancer (71.2 +/- 20.6mg/dl) was statistically higher than those for both uterine myomas (59.0 +/- 12.4mg/dl) and controls. The mean level for SA in patients with ovarian cancer was further elevated and it was statistically higher than that for benign ovarian tumors (58.8 +/- 14.3mg/dl), uterine myomas and cervical cancers. SA levels were not well correlated with tumor histologic types or clinical stages of cancer patients. As to the relationship between SA and the clinical course of cancer patients, changes in SA values were well correlated with the curability of tumor resection. The lack of specificity, however, will require careful interpretation of the SA value to assure that inflammation is not causing changes in the test values, because SA shows a transient increase due to the inflammatory reaction during the postoperative period even in patients with benign tumor. These results indicate that SA determination is highly recommended as an addition to the conventional diagnostic methods.

Adult↗

Gene for human factor X: a blood coagulation factor whose gene organization is essentially identical with that of factor IX and protein C.

Factor X is one of six vitamin K dependent proteins known to be involved in blood coagulation, the others being factor VII, factor IX, prothrombin, protein S, and protein C. In the present studies, recombinant bacteriophage containing overlapping DNA inserts coding for the gene for human factor X have been isolated and characterized. These DNA inserts code for almost the entire gene for factor X, extending from the prepro leader peptide through the 3' noncoding region of the transcription product. The organization of the gene for factor X was established by DNA sequencing to identify the location of the introns and exons in the gene. Seven introns and eight exons were identified and their intron/exon boundaries established. The seven introns interrupt the coding sequence at essentially identical locations in the amino acid sequence as the introns in the genes for human factor IX and protein C. In addition, the introns in the gene for factor X divide the coding sequence into discrete exons that code for potential structural and functional domains of the protein. This information provides strong evidence to support the suggestion that the vitamin K dependent proteins present in plasma have evolved from a single, common gene and that this ancestral gene arose through a process that involved the assembly of small protein coding units of DNA into a single gene.

Amino Acid Sequence↗

Nucleotide sequence of the cDNA coding for human complement C1r.

C1r is a zymogen of a serine protease that is involved in the activation of the first component of the classical pathway of the complement system. cDNAs coding for human C1r have been isolated from libraries prepared from poly(A) RNA from human liver and Hep G2 cells. From DNA sequence analysis, the overlapping cDNA inserts were shown to span 2493 nucleotides of the C1r mRNA, not including the poly(A) tail. The cDNA sequence coding for C1r contained a 5' noncoding region, 2115 nucleotides coding for a polypeptide precursor of 705 amino acids, and a 3' noncoding region. Some variability in the length of the 3' noncoding sequence was observed with the cDNA inserts, although most contained a polyadenylation signal followed by a poly(A) tail. The A or noncatalytic chain of C-1r, which originates from the amino-terminal end of the precursor molecule, contains a potential growth factor domain and two different pairs of internal repeats. One pair of these internal repeats is closely related to the amino-terminal sequence of C1s, while the other pair of repeats is homologous to the tandem repeats present in beta 2-glycoprotein I, complement factor B, the b subunit of factor XIII, and a single region present in the alpha 1 chain of haptoglobin. The B chain of C-1r contains the catalytic portion of the enzyme and is homologous to the trypsin family of serine proteases.

Amino Acid Sequence↗

Human liver fibronectin complementary DNAs: identification of two different messenger RNAs possibly encoding the alpha and beta subunits of plasma fibronectin.

Human fibronectin polymorphism arises from variation in the C-terminal region [e.g., Sekiguchi, K., Siri, A., Zardi, L., & Hakomori, S. (1985) J. Biol. Chem. 260, 5105-5114]. In order to verify the chemical basis of the fibronectin polymorphism, cDNAs encoding the C-terminal region of human liver fibronectin have been isolated, sequenced, and compared with cDNAs encoding so-called "cellular fibronectin" (i.e., fibronectin produced by cultured cells in vitro). Among the five independent cDNAs thus isolated, two cDNAs, named pLF2 and pLF4, differed in the nucleotide sequence at the "type III connecting segment" (IIIcs) region. pLF4 contained 192 bases in this region whereas pLF2 completely lacked these bases. S1 mapping analysis indicated that both cDNAs with and without the 192 bases are faithful copies of two fibronectin mRNA species abundantly present in human liver. Comparison of the liver cDNAs with those coding for cellular fibronectin indicates that the latter cDNAs contain the 75-base and/or 93-base extra segments at the 5' and 3' boundaries of the 192-base IIIcs region. These extra segments have the consensus sequences for the 3' splice sites at their 3' ends, suggesting that fibronectin mRNAs with partial or complete deletion of the IIIcs sequence result from alternative splicing of a primary RNA transcript. Liver fibronectin cDNAs also lacked the 270-based "extra domain" (ED) segment present in some, but not all, cDNAs encoding cellular fibronectin. Thus, cellular fibronectin appears to have three extra peptide segments, encoded by the 75-base and 93-base segments in the IIIcs region and by the 270-base ED region, that are mostly absent in the liver fibronectin.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

Characterization of a cDNA coding for human factor VII.

Factor VII is a precursor to a serine protease that is present in mammalian plasma. In its activated form, it participates in blood coagulation by activating factor X and/or factor IX in the presence of tissue factor and calcium. Clones coding for factor VII were obtained from two cDNA libraries prepared from poly(A) RNA from human liver and Hep G2 cells. The amino acid sequence deduced from the cDNAs indicates that factor VII is synthesized with a prepro-leader sequence of 60 or 38 amino acids. The mature protein that circulates in plasma is a single-chain polypeptide composed of 406 amino acids. The amino acid sequence analysis of the protein and the amino acid sequence deduced from the cDNAs indicate that factor VII is converted to factor VIIa by the cleavage of a single internal bond between arginine and isoleucine. This results in the formation of a light chain (152 amino acids) and a heavy chain (254 amino acids) that are held together by a disulfide bond. The light chain contains a gamma-carboxyglutamic acid (Gla) domain and two potential epidermal growth factor domains, while the heavy chain contains the serine protease portion of the molecule. Factor VII shows a high degree of amino acid sequence homology with the other vitamin K-dependent plasma proteins.

Amino Acid Sequence↗

[Significance of immunosuppressive acidic protein in the diagnosis and follow-up of patients with ovarian cancer, in particular as a marker for chemotherapeutic effects].

Serum immunosuppressive acidic protein (IAP) was determined in patients with ovarian cancer and was examined as a marker for ovarian cancer when, chemotherapy in particular, was applied. Samples were sera obtained from 68 ovarian cancers, 74 benign ovarian tumors, 54 cervical cancers, 57 uterine myomas and 88 healthy controls. Elevated levels of IAP were found in 89.5% of patients with ovarian cancer and this high positive ratio was not affected by tumor histologic features. The measurement of the serum IAP level is useful for the initial diagnosis of ovarian cancer because of low false positive rates (8.1%) in benign ovarian tumors and high positive rates even in the early stage of ovarian cancer. Serial determinations of serum IAP levels were well correlated with the response to the treatment (chemotherapy in particular) and the prognosis of cancer patients, even in the case of patients with leucocytopenia induced by the intensive chemotherapy. In case of recurrent patients (whose lesions were observed in the intraperitoneal space), IAP values tended to increase earlier than other conventional tumor-derived markers. Therefore, IAP may also be a useful follow-up marker for patients with ovarian cancer (particularly, for the early detection of recurrence).

Antineoplastic Combined Chemotherapy Protocols↗

Sequence of the cDNA and gene for angiogenin, a human angiogenesis factor.

Human cDNAs coding for angiogenin, a human tumor derived angiogenesis factor, were isolated from a cDNA library prepared from human liver poly(A) mRNA employing a synthetic oligonucleotide as a hybridization probe. The largest cDNA insert (697 base pairs) contained a short 5'-noncoding sequence followed by a sequence coding for a signal peptide of 24 (or 22) amino acids, 369 nucleotides coding for the mature protein of 123 amino acids, a stop codon, a 3'-noncoding sequence of 175 nucleotides, and a poly(A) tail. The gene coding for human angiogenin was then isolated from a genomic lambda Charon 4A bacteriophage library employing the cDNA as a probe. The nucleotide sequence of the gene and the adjacent 5'- and 3'-flanking regions (4688 base pairs) was then determined. The coding and 3'-noncoding regions of the gene for human angiogenin were found to be free of introns, and the DNA sequence for the gene agreed well with that of the cDNA. The gene contained a potential TATA box in the 5' end in addition to two Alu repetitive sequences immediately flanking the 5' and 3' ends of the gene. The third Alu sequence was also found about 500 nucleotides downstream from the Alu sequence at the 3' end of the gene. The amino acid sequence of human angiogenin as predicted from the gene sequence was in complete agreement with that determined by amino acid sequence analysis. It is about 35% homologous with human pancreatic ribonuclease, and the amino acid residues that are essential for the activity of ribonuclease are also conserved in angiogenin. This provocative finding is thought to have important physiological implications.

Amino Acid Sequence↗

Nucleotide sequence of the gene for human factor IX (antihemophilic factor B).

Two different human genomic DNA libraries were screened for the gene for blood coagulation factor IX by employing a cDNA for the human protein as a hybridization probe. Five overlapping lambda phages were identified that contained the gene for factor IX. The complete DNA sequence of about 38 kilobases for the gene and the adjacent 5' and 3' flanking regions was established by the dideoxy chain termination and chemical degradation methods. The gene contained about 33.5 kilobases of DNA, including seven introns and eight exons within the coding and 3' noncoding regions of the gene. The eight exons code for a prepro leader sequence and 415 amino acids that make up the mature protein circulating in plasma. The intervening sequences range in size from 188 to 9473 nucleotides and contain four Alu repetitive sequences, including one in intron A and three in intron F. A fifth Alu repetitive sequence was found immediately flanking the 3' end of the gene. A 50 base pair insert in intron A was found in a clone from one of the genomic libraries but was absent in clones from the other library. Intron A as well as the 3' noncoding region of the gene also contained alternating purine-pyrimidine sequences that provide potential left-handed helical DNA or Z-DNA structures for the gene. KpnI repetitive sequences were identified in intron D and the region flanking the 5' end of the gene. The 5' flanking region also contained a 1.9-kb HindIII subfamily repeat. The seven introns in the gene for factor IX were located in essentially the same position as the seven introns in the gene for human protein C, while the first three were found in positions identical with those in the gene for human prothrombin.

Amino Acid Sequence↗

The effect of lisuride hydrogen maleate on anterior pituitary hormones, oestradiol and cortisol in normal and hyperprolactinaemic women.

The effects of single oral doses of 0.1 mg lisuride hydrogen maleate (lisuride), a semisynthetic ergot derivative given at 09.00 h, on the serum levels of prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), growth hormone (GH), thyroid-stimulating hormone (TSH), oestradiol and cortisol were studied in six normally cycling women and six patients with hyperprolactinaemic amenorrhoea. The same subjects received placebo and the results were compared with those of lisuride. Within 1 h after oral administration of lisuride, PRL levels decreased significantly (P less than 0.05) and reached the lowest level at 4 h after ingestion and stayed low until 8 h in both normal women and hyperprolactinaemic patients. LH levels slightly but not significantly decreased after lisuride administration in hyperprolactinaemic patients. Serum cortisol levels increased at 13.00 h, probably due to the effect of meal. No significant differences between the lisuride group and placebo group were observed in GH, TSH, FSH and oestradiol levels. These results suggest that lisuride acts as a long-acting prolactin suppressor and that it has little effects on the secretion of other pituitary hormones. Therefore, this drug could be useful for treatment of hyperprolactinaemic patients.

Adult↗

Results of HMG (Humegon)-HCG therapy in 6096 treatment cycles of 2166 Japanese women with anovulatory infertility.

The effects of HMG (Humegon)-HCG therapy in 6096 cycles in 2166 Japanese women with anovulatory infertility were examined. The rates of ovulation, pregnancy, the ovarian hyperstimulation syndrome, multiple pregnancy, abortion, and malformations in the newborn were recorded, and the possible factors of multiple pregnancies were analyzed. Ovulation occurred in 73.2% of the cases and 64.5% of the treatment cycles. Pregnancy occurred in 23.0% of the cases and 8.6% of the cycles. Ovarian hyperstimulation syndrome with grade I of WHO definition or more was observed in 10.3% of the cases and 5.3% of the cycles. The incidence of the ovarian hyperstimulation syndrome was high in amenorrheic patients, who respond to progestin with bleeding. The multiple pregnancy rate was 20.5%, of which 13.0% was twins and 7.5% triplets or more. The abortion rate was 22.0%, and the abortion rate in multiple pregnancy was significantly higher (P less than 0.05) than that in singleton pregnancy. The external malformation rate was 1.68% in the 594 newborn who could be examined. No significant differences were found in maternal factors, the treatment schedule, or the ovarian response to treatment in singleton and multiple pregnancy groups. This survey revealed that the efficacy and the incidence of adverse effects of Humegon-HCG therapy in a large number of Japanese women were not different from those in Caucasians except for a lower rate of multiple pregnancy, and no special causative factors for multiple pregnancy were found.

Abnormalities, Drug-Induced↗

Cloning of cDNAs for human aldehyde dehydrogenases 1 and 2.

Partial cDNA clones encoding human cytosolic aldehyde dehydrogenase (ALDH1) and mitochondrial aldehyde dehydrogenase (ALDH2) were isolated from a human liver cDNA library constructed in phage lambda gt11. The expression library was screened by using rabbit antibodies against ALDH1 and ALDH2. Positive clones thus obtained were subsequently screened with mixed synthetic oligonucleotides compatible with peptide sequences of ALDH1 and ALDH2. One of the positive clones for ALDH1 contained an insertion of 1.6 kilobase pairs (kbp). The insert encoded 340 amino acid residues and had a 3' noncoding region of 538 bp and a poly(A) segment. The amino acid sequence deduced from the cDNA sequence coincided with the reported amino acid sequence of human ALDH1 [Hempel, J., von Bahr-Lindström, H. & Jörnvall, H. (1984) Eur. J. Biochem. 141, 21-35], except that valine at position 161 in the previous amino acid sequence study was found to be isoleucine in the deduced sequence. Since the amino acid sequence of ALDH2 was unknown, 33 tryptic peptides of human ALDH2 were isolated and sequenced. Based on the amino acid sequence data thus obtained, a mixed oligonucleotide probe was prepared. Two positive clones, lambda ALDH2-21 and lambda ALDH2-36, contained the same insert of 1.2 kbp. Another clone, lambda ALDH2-22, contained an insert of 1.3 kbp. These two inserts contained an overlap region of 0.9 kbp. The combined cDNA contained a sequence that encodes 399 amino acid residues, a chain-termination codon, a 3' untranslated region of 403 bp, and a poly(A) segment. The deduced amino acid sequence was compatible with the amino acid sequences of the tryptic peptides. The degree of homology between human ALDH1 and ALDH2 is 66% for the coding regions of their cDNAs and 69% at the protein level. No significant homology was found in their 3' untranslated regions.

Aldehyde Dehydrogenase↗

Molecular cloning of a full-length cDNA for human alcohol dehydrogenase.

We have cloned a full-length cDNA coding for human alcohol dehydrogenase (ADH; alcohol:NAD+ oxidoreductase, EC 1.1.1.1) from a human liver cDNA library constructed in phage lambda gt11. The library was screened by using a rabbit antibody against human ADH as a first probe, by the modified method of Young and Davis [Young, R. A. & Davis, R. W. (1983) Proc. Natl. Acad. Sci. USA 80, 1194-1198]. Mixed 14-mer synthetic oligonucleotides encoding Asp-Asp-His-Val-Val and Gln-Cys-Gly-Lys-Cys were used as a second probe. These amino acid sequences are considered to be common in all three subunits (alpha, beta, and gamma) controlled by the ADH1, ADH2, and ADH3 loci. Ten lambda gt11 recombinants of 35 positive plaques obtained by antibody screening contained inserted cDNAs of 1.5-2.4 kilobase pairs and were found to exhibit positive signals by hybridization with synthetic probes. One of them, with an inserted cDNA of 1631 base pairs, contained a sequence that encodes 374 amino acid residues of the human beta 1 subunit, a chain initiation codon, a chain termination codon, and additional 3' and 5' untranslated regions. A complete amino acid sequence of the human beta 1 subunit was deduced from the cDNA.

Alcohol Dehydrogenase↗

An intragenic deletion of the factor IX gene in a family with hemophilia B.

A family of seven patients severely afflicted with hemophilia B has been studied for their factor IX genes through the use of factor IX cDNA and genomic DNA probes. The patients had detectable (less than 10% of normal) factor IX antigen in urine and no detectable inhibitors in sera to factor IX protein. Based on the DNA hybridization analysis, these patients showed a partial intragenic deletion in their factor IX gene. The deletion included two exons (exons V and VI) coding for the amino acid sequence from number 85 to 195 of the factor IX protein. The deleted portion of the gene contained the entire factor IX activation peptide. The length of the deletion was estimated to be 10 +/- 0.3 kilobase pairs. This specific gene has been named FIXSeattle. In this family both the deletion and a Taq 1 restriction fragment length polymorphism can be used as a useful marker for accurate detection of female carriers of the deficient factor IX gene.

Chromosome Deletion↗

Suppressive effect of prolactin on oestrogen-induced secretion of LH by sequentially perifused rat hypothalamus-pituitary.

The effect of prolactin (Prl) on oestrogen-induced gonadotrophin secretion was examined in vitro in a sequential double chamber perfusion system. As control groups, mediobasal hypothalamus (MBH)-pituitary pairs or pituitaries without the MBHs were perifused with Medium 199. As an experimental group, MBH-pituitary pairs were perifused with Medium 199 containing 1 micrograms/ml of rat Prl. These groups were stimulated with 10(-7) M oestradiol-17 beta (E2) for 30 min, and luteinizing hormone (LH) in the serial fractions of effluent was measured. In the control group of MBH-pituitary pairs perifused with medium without Prl, secretion of LH began to rise within 30 min after the beginning of stimulation, reached a peak 30 min after the end of stimulation and then remained at a plateau for the rest of the experimental period, whereas in the control group of pituitaries alone no significant response was observed. In the experimental group perifused with medium containing Prl, LH-secretion showed peaks 20 and 80 min after the end of E2-stimulation, respectively, and the first peak was significantly (P less than 0.01) less than the level in the control group. These data demonstrate that Prl at this concentration suppressed the rapid LH release induced by E2. Its site of action is suggested to be at the hypothalamic level, and its possible mechanism of action is discussed.

Animals↗