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Biomedical subjects

C Hashimoto

Publications and source records attributed to C Hashimoto.

At least 55 records · Page 3Linked to original sources
PubMed1992

Recombinant human erythropoietin for autologous blood donation: effects on perioperative red-blood-cell and serum erythropoietin production.

To speed collection of blood for autologous transfusion during elective surgery, patients may be given recombinant human erythropoietin (r-HuEPO). In a controlled trial, we evaluated the effects of r-HuEPO on perioperative red-blood-cell and serum erythropoietin (s-EPO) production in patients donating blood before elective orthopaedic surgery. Patients were assigned randomly to receive no r-HuEPO (12 patients), or 3000 U (4), 6000 U (5), or 9000 U (4) of r-HuEPO intravenously twice a week from the time of the first blood donation. All patients received iron sulphate. 1200 ml blood was collected from each patient in three weekly donations of 400 ml. The 3000, 6000, and 9000 U treatment groups produced 284, 350, and 383 ml, respectively, of red cells during donation, and the untreated controls produced 211 ml. s-EPO concentrations were within the normal range during donation. After surgery, s-EPO concentrations peaked on postoperative day 1 in untreated patients and on day 7 in treated patients; therefore, r-HuEPO may suppress endogenous erythropoietin secretion. Although administration of r-HuEPO increases production of red blood cells, the preoperative anaemia induced by repeated phlebotomy without r-HuEPO may accelerate the postoperative secretion of endogenous erythropoietin.

Adolescent↗
PubMed1992

Phylogenetic evidence for multiple Alu source genes.

A member of the young PV Alu subfamily is detected in chimpanzee DNA showing that the PV subfamily is not specific to human DNA. This particular Alu is absent from the orthologous loci in both human and gorilla DNAs, indicating that PV subfamily members transposed within the chimpanzee lineage following the divergence of chimpanzee from both gorilla and human. These findings and previous reports describing the transpositional activity of other Alu sequences within the human, gorilla, and chimpanzee lineages provide phylogenetic evidence for the existence of multiple Alu source genes. Sequences surrounding this particular Alu resemble known transcriptional control elements associated with RNA polymerase III, suggesting a mechanism by which cis-acting elements might be acquired upon retrotransposition.

Animals↗
PubMed1992

Degradation of human pancreastatin-52 by human kidney extract.

We examined the in vitro degradation of human pancreastatin-52 (hPST-52) and a larger molecular form (approximate 15 kDa) of human PST by an enzyme extract from human kidney. The PST-degrading activity was determined from the amount of immunoreactive PST remaining after incubation of hPST-52 or the larger molecular form with the enzyme extract. Human PST-52 was degraded to smaller molecular forms within 30 min, but the larger molecule was not degraded within 90 min. Phosphoramidon, an inhibitor of endopeptidase, metal ion chelators (EDTA and 1, 10-phenanthroline) and Cu2+ prevented the degradation of hPST-52. These results indicated that the enzyme in the kidney extract degraded hPST-52 and smaller forms of the peptide, but had no effect on the 15 kDa form.

Chromatography, Gel↗
PubMed1992

Transcription dependence of DNA packaging of bacteriophages T3 and T7.

T3 and T7 phages package homologous DNA more efficiently than heterologous DNA and recombinant plasmids carrying DNA sequences necessary for DNA packaging (pac sequence). The pac sequence contains a promoter for phage RNA polymerase and transcription from the promoter is necessary for DNA packaging. T3 and T7 RNA polymerases are stringently specific for their own promoters. To examine the relationship between DNA packaging and transcription, we constructed a cleared in vitro system for packaging T3 or T7 DNA containing an ammonium sulfate fractionate of a high-speed supernatant of phage-infected cells. In the system, DNA packaging required GTP and was inhibited by the 3'-deoxy analog of GTP, ATP, or CTP. The DNA packaging activity paralleled the transcriptional activity, assayed by incorporation of [32P]UTP into acid-insoluble material. In the system, homologous DNA was packaged more efficiently than heterologous DNA, but heterologous DNA was packaged as efficiently as homologous DNA by the addition of heterologous phage RNA polymerase, demonstrating that the transcriptional specificity determines the DNA packaging specificity of T3 and T7.

Bacteriophage T7↗
PubMed1992

DNA sequences necessary for packaging bacteriophage T3 DNA.

A recombinant plasmid, pUCE1-TR, carrying a target for processing of the concatemer joint (TR) and sequences to the left of the target (E1), is efficiently packaged into transducing particles during T3 phage infection. Using this plasmid packaging/transduction system, the minimal sequences necessary for packaging of T3 DNA were determined. The TR sequence contains the targets for initiation cleavage and termination cleavage of concatemer processing (pacCR and pacCL, respectively). A plasmid lacking pacCL was packaged as efficiently as pUCE1-TR but one deleted for pacCR was packaged at a very low efficiency, showing that pacCR is essential for production of transducers but that pacCL is dispensable. DNA from transducing particles carrying a recombinant plasmid lacking pacCL or pacCR had the same right or left end as T3 DNA, respectively, but its other end was not unique. In the absence of pacCL, packaging is initiated from the DNA end created by cleavage at the pacCR and terminated at any sequence after packaging a headful of DNA. In the absence of pacCR, packaging is initiated from the DNA end created by nonspecific, inefficient cleavage and terminated by cleavage at the pacCL after packaging a headful of DNA. A 23-bp segment flanking the site where the mature right end is formed was found to support efficient formation of transducing particles. A 53-bp sequence, including a consensus sequence for the promoter for T3 RNA polymerase, was a responsible element in the E1 sequence for packaging of plasmid DNA. Deletions of the 5'-upstream sequence of the promoter sequence from the left decreased the promoter and packaging activities in parallel, but with those of the 3'-downstream sequence from the right, the packaging activity was impaired before the promoter activity, indicating that transcription from the promoter is necessary but not sufficient for T3 DNA packaging.

Base Sequence↗
PubMed1991

Heterogenous expression of decay accelerating factor and CD59/membrane attack complex inhibition factor on paroxysmal nocturnal haemoglobinuria (PNH) erythrocytes.

In order to clarify the characterization of phenotypes of paroxysmal nocturnal haemoglobinuria (PNH) erythrocytes (E), we analysed the expression of decay accelerating factor (DAF) and CD59/membrane attack complex inhibition factor (MACIF) on the membrane surface of PNH-E by means of the flow cytometric method using anti-DAF and/or CD59/MACIF monoclonal antibodies in nine PNH-patients. In two-colour analysis, this expression of PNH-E was classified into three fractions; negative, intermediate and positive according to intensity. The negative fraction was classified into two groups; one group an exclusively negative population, and the other a negative population having slightly DAF-positive E. The intermediate fraction was recognized on PNH-E of cases with PNH II-E and extremely heterogenous. In the positive fraction, this expression was almost the same as on normal E except for case 8. In single-colour analysis for DAF or CD59/MACIF, three fractions were classified as well as the definition in two-colour analysis. In single-colour analysis, the expression on PNH-E was also heterogenous in each fraction and among PNH-patients. However, the intermediate fraction for CD59/MACIF was not found on PNH-E of cases without PNH II-E, although intermediate fraction for DAF was recognized on PNH-E of some cases with PNH III-E in addition to those with PNH II-E. The results suggest that expression of CD59/MACIF and DAF on the membrane surface of PNH-E phenotypes is heterogenous and varies among PNH patients.

Adult↗
PubMed1991

Plasma membrane localization of the Toll protein in the syncytial Drosophila embryo: importance of transmembrane signaling for dorsal-ventral pattern formation.

Formation of the Drosophila embryo's dorsal-ventral pattern requires the maternal product of the Toll gene. DNA sequence and genetic analyses together suggested that the Toll gene product is a transmembrane protein which communicates information from an extracytoplasmic compartment to the cytoplasm. Using antibodies as probes, we show that the Toll protein is a 135 x 10(3) Mr glycoprotein which is tightly associated with embryonic membranes. During the syncytial stage when dorsal-ventral polarity is established, the maternal Toll protein is associated with the plasma membrane around the entire embryo. During later embryonic stages, the Toll protein is expressed zygotically on many cell surfaces, possibly to promote cell adhesion. The plasma membrane localization of the Toll protein in the syncytial embryo suggests that transmembrane signaling from the extracellular perivitelline space to the cytoplasm is required for establishment of the embryonic dorsal-ventral pattern.

Animals↗
PubMed1990

In vitro cleavage of the concatemer joint of bacteriophage T3 DNA.

Mature DNA from phage T3 or T7 is a linear duplex DNA with direct repeats at its ends known as "terminally redundant sequences." The DNA of these phages is synthesized as concatemers in which unit length molecules are joined together in a head-to-tail fashion through the terminally redundant sequences and processed to form mature DNA with coupling to DNA packaging. When linearized plasmid DNA carrying a concatemer joint, a terminally redundant sequence and its flanking sequences from the concatemer, was incubated in a defined in vitro system for packaging T3 DNA, composed of purified proheads and packaging proteins (gp 18 and gp 19), DNA was cleaved at the left end of the terminally redundant sequence. The cleavage reaction required all factors necessary for DNA packaging. The DNA fragment with the left end was preferentially protected from DNase I digestion, indicating that the cleavage reaction occurs at the left end of the terminally redundant sequence in the concatemer when DNA is packaged leftward, corresponding to the direction from the right to the left end of the T3 genome. The cleavage reaction was stimulated by high concentrations of NaCl and ATP, a condition in which DNA translocation into the head is slowed down. The cleavage reaction was not specific between T3 and T7. The right end of the concatemer joint was not required for cleavage at the left end. In the absence of ATP, DNA was extensively degraded by gp 19. gp 19 by itself had nonspecific endonuclease activity, making double-stranded breaks. The activity was inhibited by either ATP or gp 18.

DNA, Viral↗
PubMed1990

Studies on synthesis of interleukin-6 and gammaglobulin in peripheral blood mononuclear cells of patients with systemic lupus erythematosus.

Peripheral blood mononuclear cells (PBMC) from patients with systemic lupus erythematosus (SLE) proliferated spontaneously and secreted an elevated level of IgG compared with that of normal controls. However, the levels of interleukin-6 (IL-6) produced by PBMC from patients with SLE with or without pokeweed mitogen (PWM) stimulation showed no significant difference from those of normal controls. The levels of IL-6 secreted spontaneously from PBMC of SLE patients correlated inversely with the percent and the absolute number of CD19 positive cells in PBMC, but not with the levels of IgG and IgM secreted spontaneously from PBMC. There was no significant difference in the levels of IgG produced by PBMC stimulated with IL-6 and also in the levels of IL-6 synthetized by T and B cells between SLE patients and normal controls. These data suggest that IL-6 may not play an important role in the hypergammaglobulinemia in SLE.

Adult↗
PubMed1989

[An autopsy case of a patient with myasthenia gravis who showed various symptoms of collagen diseases and complicated with malignant thymoma].

A 37-year-old man suffered from photosensitivity and urinary casts with serological findings of positive anti-DNA antibody, LE cells and false positive VD reaction in September of 1979. He developed general fatigue, dyspnea and diplopia with ptosis of bilateral eyelids in November of 1979, which were improved by the anti-cholinesterase drugs. In January of 1980, he had an attack of unconsciousness and his chest X-ray film showed several tumorous shadows in the anterior mediastinum and middle and lower lung fields. Treating him with chemotherapy of VEMP, the pulmonary shadows disappeared. However, he developed severe muscle weakness with an elevated CPK (430 mU/ml) and a myogenic EMG pattern along with an increased anti-acetylcholine receptor antibody (243 n Mol/l), dysphagia and eyelid-ptosis. He died in September of 1985 and his autopsy disclosed a malignant thymoma of mixed type in the anterior mediastinum and an atrophy and fibrosis with infiltration of inflammatory cells in the striated muscles.

Adult↗
PubMed1988

The Toll gene of Drosophila, required for dorsal-ventral embryonic polarity, appears to encode a transmembrane protein.

The Toll gene of Drosophila, a maternal effect gene that plays a central role in the establishment of the embryonic dorsal-ventral pattern, has been cloned using P element tagging. A 5.3 kb poly(A)+ ovarian transcript from the cloned region was purified by hybrid selection with the cloned DNA. This purified transcript complements the Toll mutant phenotype when injected into Toll- embryos, which proves that it is the Toll transcript. The sequence of cDNAs suggests that the Toll protein is an integral membrane protein with a cytoplasmic domain and a large extracytoplasmic domain. The putative extracytoplasmic domain contains at least 15 repeats of a 24 amino acid, leucine-rich sequence found in both human and yeast membrane proteins.

Alleles↗
PubMed1988

Developmentally regulated expression of the calcitonin gene related peptide (CGRP) in rat lung endocrine cells.

Calcitonin (CT) and the calcitonin gene-related peptide (CGRP) are generated by alternative RNA processing from a single CT/CGRP gene. Recently, we reported the existence of CGRP-immunoreactivity and CGRP mRNA in endocrine cells or Kulchitsky (K) cells of human and rat lung [Wada et al. 1987b]. In this report, an examination was made of developmental changes in the expression of the CGRP gene in rat lungs by immunohistochemistry, radioimmunoassay (RIA) and Northern hybridization. CGRP-positive K-cells in lung tissue appeared on the 18th day of gestation. Their number was greatest on the 20th day of gestation and then decreased postnatally. The level of CGRP in rat lung was found to be highest in a 1-day-old neonate by RIA. In the Northern hybridization of rat lung using the CGRP 3' non-coding region (exon 6) of the first human CT/CGRP gene as the probe, 1.0 kilobase (kb) CGRP mRNA was found to be abundant on the 20th day of gestation and in a 1 day-old neonate. It thus appears that CGRP in rat lung is essential for pulmonary adaptation at birth and/or from the last intrauterine stage to the early neonatal period.

Animals↗
PubMed1988

Packaging and transduction of non-T3 DNA by bacteriophage T3.

A defined in vitro system for packaging T3 DNA also packaged other linear DNAs, including T4, lambda, and plasmid DNAs. The packaging capacity was determined to be 40 kb (kilobase pairs) by measuring the packaged length of T4 DNA. Packaged lambda and plasmid DNAs were injected into host cells to form plaques and transductants, respectively. The yield of transducers increased by using artificially ligated plasmid oligomers. The T3 mutant in gene 3 endonuclease (T3 3-) packaged plasmid DNA during abortive infection and transduced it into the recipient. Transduction of recombinant plasmids was not affected by the presence of the terminally redundant sequence (TR sequence) but increased by 4 orders of magnitudes when the genetic right-end 2.7-kb sequences, containing gene 19 (E1) but lacking TR, were present and by 7 orders when both E1 and TR sequences were present. However, these sequences did not increase transduction of these plasmids by T7 3-. Analysis of the structure of transduced plasmid DNAs indicates that transducing particles carry head-to-tail oligomers of plasmid DNA with the same termini as those of T3 genomic DNA. The mechanism of formation of transducing particles is discussed.

Bacteriophage lambda↗
PubMed1986

A small nuclear ribonucleoprotein associates with the AAUAAA polyadenylation signal in vitro.

RNAs containing the polyadenylation sites for adenovirus L3 or E2a mRNA or for SV40 early or late mRNA are substrates for cleavage and poly(A) addition in an extract of HeLa cell nuclei. When polyadenylation reactions are probed with ribonuclease T1 and antibodies directed against either the Sm protein determinant or the trimethylguanosine cap structure at the 5' end of U RNAs in small nuclear ribonucleoproteins, RNA fragments containing the AAUAAA polyadenylation signal are immunoprecipitated. The RNA cleavage step that occurs prior to poly(A) addition is inhibited by micrococcal nuclease digestion of the nuclear extract. The immunoprecipitation of fragments containing the AAUAAA sequence can be altered, but not always abolished, by pretreatment with micrococcal nuclease. We discuss the involvement of small nuclear ribonucleoproteins in the cleavage and poly(A) addition reactions that form the 3' ends of most eukaryotic mRNAs.

Adenoviridae↗
PubMed1984

U4 and U6 RNAs coexist in a single small nuclear ribonucleoprotein particle.

U4 and U6 RNAs of mammalian cells possess extensive intermolecular sequence complementarity and hence have the potential to base pair. A U4/U6 RNA complex, detectable in nondenaturing polyacrylamide gels, is released when human small nuclear ribonucleoproteins (snRNPs) containing U1, U2, U4, U5, and U6 RNAs are dissociated with proteinase K in the presence of sodium dodecyl sulfate. The released RNA/RNA complex dissociates with increasing temperature, consistent with the existence of specific base-pairing between the two RNAs. Since U6 RNA is selectively released from intact snRNPs under the same conditions required to dissociate the U4/U6 RNA complex, the RNA-RNA interaction may be sufficient to maintain U4 and U6 RNAs in the same snRNP particle. The biological implications of these findings are discussed.

Base Composition↗
PubMed1983

Sequential association of nucleolar 7-2 RNA with two different autoantigens.

Anti-Th serum from a patient with systemic lupus erythematosus immunoprecipitates from both human and mouse cell extracts small ribonucleoproteins containing 7-2 RNA, 8-2 RNA, and the Ro RNAs. Human 7-2 RNA, which must be complexed with protein to be antigenic, is about 300 nucleotides long and has mostly pG at its 5' end. A related 7-2 RNA, precipitated by anti-La antibody, gives identical Tl and pancreatic RNase fingerprints, but has more pppG at its 5' end. La 7-2 RNA is, therefore, likely to be a precursor of Th 7-2 RNA. The synthesis of 7-2 RNA in isolated nuclei exhibits a pattern of sensitivity to alpha-amanitin that is characteristic for RNA polymerase III transcription. Thus, 7-2 RNA can be added to the list of mammalian RNA polymerase III transcripts that initially bind the La protein and then become incorporated into other types of antigenic RNP particles.

Animals↗