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Biomedical subjects

S Sekiguchi

Publications and source records attributed to S Sekiguchi.

At least 109 records · Page 6Linked to original sources
PubMed1996

[Emergent coronary bypass grafting after acute myocardial infarction].

In an attempt to examine various factors affecting the short- and long-term results of emergent coronary bypass graft surgery (ECABG) after an acute myocardial infarction (AMI), all patients undergoing ECABG without associated procedures at our institution from January 1987 to July 1995 were reviewed. Forty eight patients underwent ECABG after AMI. The hospital mortality rate was 20.8%. The charts of these patients were reviewed with regard to sex, age, preoperative shock, location of AMI, type of infarction, coronary anatomy, presence of postinfarction angina, technique of myocardial preservation, use of saphenous vein graft (SVG) alone, time from AMI to operation and short and long-term outcome. Univariate analyses showed that three factors were significantly associated with increased hospital death: preoperative shock (p = 0.001), type of infarction (p = 0.01), use of SVG alone (p = 0.003). Follow-up was 100% complete at a mean time of 36.4 +/- 4.8 months. Of all patients 77.0% were alive at 5 years after operation. Univariate comparison of survival curves and coronary event free curves showed that use of SVG alone was associated with decreased survival (p = 0.0009) and event free (p = 0.02) rates. Patients with non-Q-wave infarction and without cardiogenic shock may undergo ECABG relatively safely at any time. The use of internal thoracic artery at ECABG without cardiogenic shock does not increase hospital mortality and improves both long-term survival and freedom from coronary events.

Adult↗
PubMed1995

Endotoxin antagonism by a synthetic lipid A analogue, DT-5461, with low endotoxicity in human peripheral blood monocytes.

We examined the molecular mechanism of DT-5461-induced LPS antagonism in human peripheral blood monocytes. Dose-response studies revealed that LPS-induced IL-1 and TNF-alpha production was apparently totally suppressed in a competitive manner by a 10-fold excess of DT-5461. A 10-fold excess of DT-5461 significantly blocked the binding of FITC-LPS to the monocytes. DT-5461 suppressed IL-1 and TNF-alpha mRNA expression in LPS-activated monocytes. Western blots showed that DT-5461 suppressed the LPS-induced tyrosine phosphorylation of p42mapk/ERK2. These results suggested that the competitive binding inhibition and repression of early intracellular signaling involved in DT-5461-mediated LPS antagonism.

Adjuvants, Immunologic↗
PubMed1995

Prevalence of Borna disease virus RNA in peripheral blood mononuclear cells from blood donors.

The presence of Borna disease virus (BDV) in peripheral blood mononuclear cells (PBMC) of 100 blood donors from Sapporo and 72 blood donors from Tokyo was examined using nested reverse transcriptase/polymerase chain reaction amplification with specific-primers for BDV p24. Anti-BDV p24 antibodies in the plasma of the 100 blood donors from Sapporo also were studied by enzyme-linked immunosorbent assay and by Western blot. BDV RNA was detected in 3 (4.2%) of the 72 PBMC samples from Tokyo, and in 5 (5%) of the 100 PBMC samples from Sapporo. In contrast, anti-p24 antibodies were found in only 1 (1%) of the donors from Sapporo. These results suggest that BDV infection in humans may be more widespread than previously thought.

Adolescent↗
PubMed1995

Growth-blocking peptide titer during larval development of parasitized and cold-stressed armyworm.

Growth-blocking peptide (GBP) has been isolated for the first time from the haemolymph of the host armyworm Pseudaletia separata whose development was halted in the last larval instar stage by parasitization with the parasitoid wasp Cotesia kariyai. Recent studies demonstrated that GBP not only exists in the plasma (haemolymph without cells) of parasitized last instar larvae, but also in the plasma of nonparasitized penultimate (5th) instar larvae. Monoclonal antibodies were prepared to measure the titers of GBP in nonparasitized and parasitized larval plasma. One of three monoclonal antibodies raised against GBP, which is the most specific for GBP, was used to quantify the concentration of plasma GBP. As this antibody recognized two plasma peptides other than GBP in crude plasma fractions, each plasma peptide fraction was separated by a reversed phase HPLC, and then plasma GBP level was measured by ELISA. The highest level of plasma GBP detected on Day 0 of the penultimate instar larvae was gradually decreased throughout the larval growth except for the temporary increase on Day 0 of last larval instar. After parasitization on Day 0 of last larval instar, two peaks of plasma GBP titer were detected during the last larval instar, one day and six days after parasitization. This characteristic increase and decrease in plasma GBP level was also observed by transferring last instar larvae of the armyworm from 25 to 10 degrees C, as a result of which larvae delayed pupation by more than 15 days. From these results, it is reasonable to propose that plasma GBP in lepidopteran larvae might control certain upstream steps in a cascade of events leading to pupation; thus, an elevated level of plasma GBP interferes with normal metamorphosis from larvae to pupae.

Amino Acid Sequence↗
PubMed1995

Relationship between functional levels and movement in tetraplegic patients. A retrospective study.

The aim of the present study was to set targets for each spinal lesion level after determining the relationship between the spinal lesion level and movement abilities in patients with tetraplegia following injury to the cervical cord. A total of 109 patients, 96 men and 13 women were included in the study. We mainly examined locomotion and transfer capabilities according to Zancolli's classification. The results of this study showed that 50% of the patients classified as C6A, 75% of C6B1 and 96% of the patients classified C6B2 accomplished bed transfer. The number of patients who could manage toilet transfer was 53% in the group classified as C6B1 and 85% in group C6B2. These results suggest that achievement of those classified as C6B2 is a clue to the assumption that the patient will achieve toilet transfer capability and can perform ADL independently.

Activities of Daily Living↗
PubMed1995

Incidence of human parvovirus B19 DNA detection in blood donors.

1000 serum samples from blood donors were tested for human parvovirus B19 (B19) DNA by a nested PCR assay: six samples were positive for B19 DNA. The frequency was 1/167 (0.6%), considerably higher than previous surveys (0.004-0.03%). Five of the six samples were also positive for anti-B19 IgM, indicating an acute phase of infection. It is recommended to screen for B19 DNA in blood products to prevent transfusion mediated viral infection for those susceptible such as immunocompromised patients and pregnant women.

Antibodies, Viral↗
PubMed1995

Human cytomegalovirus DNA is not detectable with nested double polymerase chain reaction in healthy blood donors.

The PCR method was introduced to detect cytomegalovirus (CMV) DNA from 189 peripheral blood samples of volunteer donors. We adopted the nested double PCR method with primers specific for immediate early gene 1 followed by electrophoresis and ethidium bromide staining. This nested double PCR method was sensitive enough to detect approximately a single copy of CMV DNA. However, we failed to obtain positive amplification of CMV DNA from any of these donor samples. In contrast, CMV DNA could be detected in all 3 tested immunocompromised patients who had undergone bone marrow transplantation. These results support our previous report that the frequency of CMV DNA is of an order lower than 1 copy/10(5) leucocytes in the peripheral blood of healthy seropositive individuals.

Adolescent↗
PubMed1995

Molecular basis of CD36 deficiency. Evidence that a 478C-->T substitution (proline90-->serine) in CD36 cDNA accounts for CD36 deficiency.

CD36 deficiency is divided into two subgroups: neither platelets nor monocytes express CD36 (type I deficiency), and monocytes express CD36 in spite of the lack of platelet CD36 (type II deficiency). We have already demonstrated that a 478C-->T substitution (proline90-->serine) in platelet CD36 cDNA predominates in type II deficiency (Kashiwagi, H., S. Honda, Y. Tomiyama, H. Mizutani, H. Take, Y. Honda, S. Kosugi, Y. Kanayama, Y. Kurata, and Y. Matsuzawa. 1993. Thromb. Haemostasis. 69:481-484). In this study, we revealed that monocyte CD36 cDNA from two type II deficient subjects was heterozygous for C478 and T478 form, while platelet CD36 cDNA of these subjects consisted of only T478 form. In a type I deficient subject, both platelet and monocyte CD36 cDNA showed only T478 form. Expression assay using C478 or T478 form of CD36 cDNA transfected cells revealed that there was an 81-kD precursor form of CD36, and that the maturation of the 81-kD precursor form to the 88-kD mature form of CD36 was markedly impaired by the substitution. The mutated precursor form of CD36 was subsequently degraded in the cytoplasm. These results indicate that the 478C-->T substitution directly leads to CD36 deficiency via defects in posttranslational modification, and that this substitution is the major defects underlying CD36 deficiency.

Amino Acid Sequence↗
PubMed1995

Pulmonary paragonimiasis with pleural effusion containing paragonimus ova: sonographical appearance of pleural effusion.

In the pleural effusion of a 46-year-old man with pulmonary paragonimiasis, numerous floating particles containing parasitic ova and granulation tissue were observed. The floating particles appeared as diffuse hyperechoic foci in the anechoic pleural effusion on ultrasonography. We concluded that rupture of the intrapulmonary paragonimiasis lesion into the pleural cavity caused the formation of these floating particles.

Humans↗
PubMed1995

Interferon-alpha-induced apoptosis in human erythroid progenitors.

Recombinant human interferon-alpha (rIFN-alpha) inhibits erythropoiesis, in vivo and in vitro. In an attempt to clarify mechanisms related to this inhibition, effects of rIFN-alpha on highly purified human peripheral blood burst-forming units-erythroid (BFU-E) (20-60% purity) were compared with effects on erythroid progenitors in various stages of development. Day-1 and -7 cultured cells were equivalent to primitive BFU-E and colony-forming units-erythroid (CFU-E), respectively. Day-1 BFU-E supported by recombinant human erythropoietin (rEpo) and interleukin-3 (rIL-3) was inhibited by rIFN-alpha in a dose-dependent manner, and a significant inhibition occurred at 2000 U/mL rIFN-alpha. Limiting dilution analysis demonstrated that rIFN-alpha directly inhibits BFU-E rIFN-alpha inhibited the proliferative capacity or the colony expression of erythroid progenitors, with no relation to the stage of development, but inhibition of differentiation was not apparent. This evidence suggested that apoptosis of erythroid progenitors was induced by IFN-alpha. When day-7 cells were incubated with IFN-alpha in the presence of rEpo, there was an increased breakdown of total cellular DNA into DNA fragments of less than 5 kb; hence, the inhibitory effect of IFN-alpha on erythroid progenitors may mediate apoptosis.

Adult↗
PubMed1995

[Coronary artery disease in patients with abdominal aortic aneurysm].

To evaluate the influence of coronary artery disease (CAD), we reviewed 102 patients who underwent elective repair of abdominal aortic aneurysm (AAA) between 1982 and 1992. Prior to surgery, all patients underwent clinical evaluation for the presence of CAD including dipyridamole thallium scintigraphy. They were classified into the following groups: Group I (n = 66), no clinical evidence of CAD; Group II (n = 26), clinical evidence of stable CAD; Group III (n = 10), unstable CAD. Coronary angiography (CAG) was performed in group II and group III patients only. All patients in group I and group II underwent elective repair of their AAA without coronary revascularization. Eight patients in group III underwent CABG followed by elective AAA repair within two months. One of two patients who had impending ruptured AAA underwent combined CABG and AAA repair as a single operation and the other underwent AAA repair followed by CABG. One case of perioperative myocardial infarction occurred in group II, but there was no early postoperative death related to cardiac disease in group I and II. In group III, however one patient who underwent combined surgery died of low-output syndrome in the early postoperative period, no death or myocardial infarction occurred following staged operation in the other nine patients. This present results support the contention that CAG is not necessary in all AAA patients, and that they can be managed according to appropriate risk by a selective approach based upon clinical assessment of their CAD. It is also apparent that a staged operation can be performed very safely in patients with unstable CAD.

Adult↗
PubMed1994

Production of human granulocyte colony stimulating factor by various kinds of stromal cells in vitro detected by enzyme immunoassay and in situ hybridization.

Production of human granulocyte colony stimulating factor (G-CSF) by stromal cells was studied in vitro. Induction of G-CSF by interleukin 1 (IL-1) and lipopolysaccharide (LPS) was compared using enzyme immunoassay in various kinds of stromal cells. Primary human bone marrow stromal cells, a human bone marrow-derived stromal cell line (KM-102), and peripheral blood monocytes secreted small amounts of G-CSF without stimulation, while vascular endothelial cells and skin fibroblasts secreted G-CSF only when induced by IL-1 or LPS. The production of G-CSF by monocytes was stimulated predominantly by LPS, whereas that by KM-102 cells, endothelial cells, and fibroblasts was induced by IL-1 but much less so by LPS. IL-1 and LPS stimulated similar levels of G-CSF production by primary bone marrow stromal cells which consisted of various types of cells. In situ hybridization for G-CSF mRNA showed that only a small proportion of primary bone marrow stromal cells expressed a large amount of G-CSF mRNA upon stimulation. The positive cells were round or oval in shape, while most of the spindle-shaped stromal cells were negative for specific grains. Although further characterization of positive cells is needed, the results suggest that bone marrow stromal cells are heterogeneous in terms of their capacity for G-CSF production.

3T3 Cells↗
PubMed1994

Recombinant human interleukin-4 inhibits the production of granulocyte-macrophage colony stimulating factor by blood mononuclear cells.

The effect of recombinant human (rh) interleukin-4 (rIL-4) on human blood BFU-E was investigated using two populations of cells: platelet-depleted low-density mononuclear cells (FH,Pl- cells), as unpurified cells, and highly purified BFU-E. When FH,Pl- cells were cultured with rh-erythropoietin (rEp), rIL-4 inhibited BFU-E growth in a dose-dependent manner. However, the addition of rIL-4 did not affect rh-interleukin-3 (rIL-3) supported BFU-E growth. Limiting dilution analysis (LDA) of FH,Pl- cells showed that rIL-4 suppressed endogenous production of burst-promoting activity (BPA) by accessory cells. Highly purified BFU-E were used as target cells to measure BPA in the conditioned medium (CM) that was prepared by FH,Pl- cells. When 100 purified BFU-E were cultured in 0.5 ml clots with 20% (vol/vol) of the CM, the number of BFU-E colonies was increased by the CM. The increase was significantly reduced by the addition of the CM prepared in the presence of rIL-4, but anti-IL-4 blocked the effect of rIL-4. The concentration of IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF) in CM was determined by an enzyme-linked immunoadsorbent assay (ELISA). The spontaneous production of GM-CSF but not IL-3 was detected, and this was significantly decreased in the presence of rIL-4. Anti-GM-CSF but not anti-IL-3 inhibited CM supported BFU-E growth, indicating that the main BPA in the CM is GM-CSF and that rIL-4 suppresses the spontaneous production of GM-CSF by accessory cells. From these studies, we conclude that rIL-4 has a unique mechanism as a negative regulator on erythropoiesis through the inhibition of BPA production by blood mononuclear accessory cells.

Adult↗
PubMed1994

A human monoclonal antibody to high-frequency red cell antigen Jra.

A human-mouse heterohybridoma (HMR0921) secreting human monoclonal IgG3, lambda antibody was produced from peripheral blood lymphocytes of a healthy blood donor with serum antibody to Jra, by EBV transformation and hybridization with mouse myeloma cell line P3X63Ag8.653. The reactivity of HMR0921 antibody was assessed by antiglobulin test with a panel of red cells including 14 different rare blood types. Only Jr(a-) red cells were negative. The strict specificity of this antibody to Jra antigen was further confirmed by absorption test with fluorescence flow cytometry. On screening of 28,744 blood donor samples by HMR0921 antibody, we detected 19 agglutination-negative samples, which were confirmed as Jr(a-) by conventional anti-Jra antisera. Therefore, our HMR0921 antibody is extremely useful for detecting rare Jr(a-) blood.

Animals↗