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Biomedical subjects

M Higuchi

Publications and source records attributed to M Higuchi.

At least 307 records · Page 17Linked to original sources
PubMed1988

A human macrophage hybridoma producing a cytotoxic factor distinct from TNF, LT, and IL-1.

A stable human macrophage hybridoma was established by somatic cell fusion between human peripheral blood monocyte-derived macrophages and an 8-azaguanine resistant clone of a human histiocytic lymphoma cell line U-937 (clone U-937-F9). The hybrid cell line (F9P) exhibited typical macrophage-like morphology and had 30 more chromosomes than U-937-F9 cells. Its macrophage characteristics were confirmed by the manifestation of intracellular nonspecific esterase, the detection of Mo-2 and LEU-M3 antigens on the cell surface, and the demonstration of phagocytic activity. Furthermore, when stimulated with lipopolysaccharide (LPS), this cell line could secrete a considerable amount of a cytotoxic factor (CTF). Distinct from the hybrid cell line, the parental U-937-F9 cells expressed neither Mo-2 nor LEU-M3 antigens on the cell surface, did not show phagocytic activity, and their culture supernatants did not show cytotoxic activity even after LPS stimulation. The activity of CTF in the culture supernatant of the LPS-stimulated hybrid cells could not be neutralized with anti-tumor necrosis factor, anti-interleukin-1, or anti-lymphotoxin antibodies. The CTF had a relative molecular mass of 45-60 x 10(3) daltons as determined by gel filtration on a column of Superose 12, and an isoelectric point of 5.1. The cytotoxic activity was also induced when the hybrid cells were stimulated with the concentrated supernatants of a human T-cell hybridoma containing macrophage activating factor for cytotoxicity or with LP3 tumor cells which were used as target cells.

Antibodies↗
PubMed1988

Prenatal diagnosis of alpha-1-antitrypsin deficiency using oligonucleotide probe analysis.

Prenatal diagnosis of a pregnancy at risk for alpha-1-antitrypsin deficiency was performed by oligonucleotide probe analysis using M- and Z-specific oligonucleotides. The result was confirmed by the alternative approach utilizing restriction fragment length polymorphisms. Application of oligonucleotide analysis requires only fetal tissue if proteinase inhibitor types are accurately determined within the family. Our modified protocol is easy to carry out and is practicable in all laboratories where the Southern blot procedure has been established.

DNA↗
PubMed1988

Haemophilia A: carrier detection by DNA analysis.

From 46 families of predominantly German origin, afflicted with haemophilia A, 178 females were tested for carrier status. Two polymorphic restriction endonuclease sites, the extragenic marker locus DXS 52 (St 14 probe) and the intragenic Bcl I RFLP were investigated in these families. In some cases the results were corroborated by identifying (i) deletions within the factor VIII:C gene and (ii) eliminating a restriction endonuclease site. Two new alleles of the DXS 52 marker locus were found. According to this strategy, 27 women were classified as carriers and 74 as non-carriers. Forty-six women were classified as carriers according to pedigree analysis. Twenty-five females of families with sporadic cases and 6 test persons, who had mothers who where homozygous for the marker alleles, were diagnosed by additional use of conventional carrier detection.

Alleles↗
PubMed1988

Purification of rat cutaneous mast cells with Percoll density centrifugation.

The skin is the major site on anaphylaxis, and cutaneous mast cells have an important role in its reactions. The isolation and purification of rat cutaneous mast cells are described here. Rat abdominal skin was digested with collagenase and hyaluronidase, and centrifuged with Percoll. The buoyant density of cutaneous mast cells was high, and relatively pure mast cells were obtained. The purity of cutaneous mast cells was 74% +/- 2.4% before and 50.0% +/- 6.4% after Percoll density centrifugation; peritoneal mast cells revealed 5.8% +/- 1.3% purity before and 61.0% +/-10.6% purity after the same procedure. The isolated cutaneous cells released 21.3% +/- 3.8% histamine and the peritoneal mast cells released 55.5% +/- 3.8% histamine upon stimulation with 10 micrograms/ml compound 48/80. These findings suggest that there are functional subsets of connective tissue mast cells.

Animals↗
PubMed1988

Blood lactate accumulation during exercise in older endurance runners.

To delineate the possible age-related differences in blood lactate response during exercise and its relations to endurance performance, 34 male runners (aged 21 to 69 years) performed an incremental treadmill running test. There were no significant differences in training distance and relative body fat among younger runners (YR), middle-aged runners (MR), and older runners (OR). The 5-km run time slowed with age, but was ranked at relatively the same level in each age group. OR had a 23% (P less than 0.001) and 12% (P less than 0.01) lower maximal oxygen uptake (VO2max) and a 22% (P less than 0.001) and 11% (P less than 0.001) slower 5-km run time than YR and MR, respectively. However, mean VO2 corresponding to 4 mM of blood lactate (OBLA VO2) was the same among the groups when expressed as %VO2max (YR; 84.3%, MR; 85.9%, OR; 85.9%). Significant correlations were found between OBLA VO2 (ml.kg-1.min-1) and 5-km run time in each group (YR; r = -0.648, P less than 0.05; MR; r = -0.658, P less than 0.01; OR; r = -0.680, P less than 0.05). These results suggest that OR attain a given blood lactate level at almost similar %VO2max to YR and MR and that OBLA VO2 in OR is useful for evaluating an endurance performance as well as in YR and in MR.

Adult↗
PubMed1988

The effects of physical exercise on plasma lipoprotein and apolipoprotein metabolism in elderly men.

The present study was undertaken to evaluate the effects of physical exercise on plasma lipoprotein and apolipoprotein metabolism in elderly men. We measured plasma concentrations of lipids, lipoproteins, and apolipoproteins (apo) in 12 elderly runners (OR), 12 elderly sedentary controls, 16 young runners (YR), and 15 young sedentary controls. Although there were no significant differences in plasma levels of cholesterol (Ch), triglyceride, and phospholipid between two old groups and between two young groups, OR and YR had decreased levels of VLDL-Ch (42% and 59% of respective control) and LDL-Ch (90%, 94%), and increased levels of HDL-Ch (133%, 112%), apo A-I (109%, 101%), and apo A-II (109%, 105%). These data indicate that physical exercise may have favorable effects on plasma concentrations of lipoproteins and apolipoproteins in OR as well as in YR, and affect HDL-lipids, HDL-proteins, and ratio of HDL-proteins/HDL-lipids.

Adult↗
PubMed1988

Plasma lipid and lipoprotein profile in elderly male long-distance runners.

The purpose of this study was to evaluate plasma lipid and lipoprotein profiles in 30 elderly male long-distance runners (aged 66 +/- 5 years, body fat 12 +/- 2%, mean +/- SD) by comparing them with 30 middle-aged untrained men (43 +/- 8 years, 17 +/- 3%), 30 middle-aged endurance-trained men (45 +/- 8 years, 12 +/- 2%) who were matched for training distance to the elderly runners, and 15 elderly sedentary persons (65 +/- 4 years, 16 +/- 4%). Both elderly and middle-aged runners averaged 43 km/week in the latest year. Maximal oxygen uptake in the elderly runners (48 +/- 5 ml/kg/min) was 60% higher than in age-matched untrained men, but 15% lower than in middle-aged runners. Plasma high-density lipoprotein cholesterol (HDLC) was significantly higher in the elderly runners than in their age-matched counterparts (77 vs. 59 mg/dl), but not different from the middle-aged runners. The middle-aged runners had lower plasma low-density lipoprotein cholesterol (LDLC) concentrations than their untrained counterparts (114 vs. 129 mg/dl), whereas LDLC level in the elderly runners was almost identical to that of the age-matched untrained men (127 vs. 119 mg/dl). Total cholesterol concentration in the elderly runners (219 mg/dl) was 11% higher than in the age-matched untrained men, whereas there was no difference between the middle-aged trained and untrained men. The remarkable reduction of the LDLC/HDLC ratio in the elderly runners, therefore, is attributable to the elevated HDLC rather than lowered LDLC compared with the age-matched sedentary men (1.7 vs. 2.2).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Evaluation of random cDNA clones as probes for human restriction fragment length polymorphisms.

We constructed two human cDNA libraries and selected clones hybridizing with more than five fragments of digested genomic DNA. We assume that these cDNAs detect sequences belonging to gene families. Compared with cDNAs derived from mRNAs of other tissues, the cDNAs of lymphocytes contained a higher proportion of these selected species of cDNA. We assume that these extra cDNAs are tissue-specific. In parallel tests, cDNAs belonging to gene families detected more restriction fragment length polymorphisms than did genomic probes, due to the larger number of restriction sites that can be checked using one probe. However, the chromosomal assignment of these polymorphisms often proved to be very difficult. In addition, we noticed that the mean length of EcoRI fragments hybridizing with our cDNAs is greater than the mean length of fragments hybridizing with randomly chosen genomic probes, possibly due to methylation connected with the inactivation of related active gene sequences.

Chromosome Mapping↗
PubMed1988

[Morphological and immunohistochemical study on specimens of trophoblastic diseases in which the presence of a villous formation could not be established].

The histopathological discrimination between malignant trophoblastic diseases and benign trophoblastic diseases depends on the presence or absence of a villous structure. However, molar extravillous trophoblasts and cells in some placental site trophoblastic tumors (PSTT) of a benign nature, lack a villous structure. We therefore observed the morphology of trophoblastic cells which do not constitute a villous structure, including choriocarcinoma cells, and analyzed the location of placental proteins in these cells immunohistochemically. The results were as follows: 1. Molar extravillous trophoblasts were composed of large mononuclear cells and multinuclear cells. Most of them were positive for hPL and negative for hCG and SP1. 2. Choriocarcinoma consisted of cytotrophoblast-like cells, syncytiotrophoblast-like cells, large mononuclear cells and multinuclear cells resembling large mononuclear cells. HCG was noted in syncytiotrophoblast-like cells and large mononuclear cells, while hPL and SP1 were found only in syncytiotrophoblast-like cells. 3. PSTT was made up of large mononuclear cells and multinuclear cells which contained abundant hPL and very little hCG and SP1 or none at all. Molar extravillous trophoblasts were clearly distinguishable from choriocarcinoma cells in terms of their morphology and the location of placental proteins. In contrast, it seemed difficult to distinguish cells of PSTT from molar extravillous trophoblasts on a cell level.

Chorionic Gonadotropin↗
PubMed1988

A somatic mosaic for haemophilia A detected at the DNA level.

A partial gene deletion of about 1700 to 2000 bases spanning exon 3 and part of IVS-3 was identified in one patient with severe haemophilia A. Extensive DNA analysis of his family members revealed that the mother of the proband is a somatic mosaic for an abnormal factor VIII gene, because the defective gene could be identified in a considerable fraction of the leucocytes as well as of the cultured fibroblasts of the mother. This observation is important in estimating the recurrence risk in families of sporadic cases.

Cells, Cultured↗
PubMed1988

[Lateral approach to the anterior foramen magnum tumor: report of two cases].

A procedure for lateral approach to the ventral portion of the foramen magnum and the upper cervical canal is described. The patient was placed in the lateral position and a curvilinear skin incision was made from the retoroauricular area down to the lateral neck across the sternocleidomastoid muscle, and underlying muscle layers were divided. A suboccipital hemicraniotomy and hemilaminectomies were performed with an air drill. Because the medulla and the cervical cord are displaced posteriorly by the tumor, there is no need to retract those structures and all the tumors can be removed under direct vision. This procedure was applied on the two patients with ventrally situated foramen magnum tumors; a neurenteric cyst and neurofibroma, and both of the tumors were successfully removed under direct vision. Major advantages of this approach are that there is no need for retraction of the spinal cord, and there is excellent exposure of an anteriorly located tumor, no postoperative cervical spine instability, no risk for CSF leak and infection, which effects are often found after the anterior approach. The procedure, like the posterior approach, is relatively simple.

Adult↗
PubMed1988

Tumoricidal activity of lymphotoxin (tumor necrosis factor beta) in vivo: its effects on macrophages.

We investigated the cytotoxic activity of recombinant human lymphotoxin (rHuLT) against Meth A sarcoma in vitro and in vivo. In direct cytotoxic assay, Meth A cells showed very low, if any, sensitivity to rHuLT. However, rHuLT was found to be strongly cytotoxic for subcutaneously implanted Meth A cells. In order to explain this discrepancy, we examined the indirect effects of rHuLT on Meth A cells particularly through macrophages. rHuLT showed macrophage chemotactic activity in vitro and also in vivo. Thus, injection of rHuLT into the mouse peritoneal cavity caused migration of macrophages to the peritoneal cavity. In addition, histologic analysis revealed that 6 h after intratumor injection of rHuLT, nonspecific esterase-positive cells started to migrate into Meth A tumor tissues, and after a further 24 h, a larger number of nonspecific esterase-positive cells had migrated into the Meth A tumor tissues. Moreover, peritoneal exudate cells induced by rHuLT showed considerably higher cytotoxic activity against Meth A cells than proteose peptone- or phosphate-buffered saline-induced peritoneal exudate cells. Furthermore, the cytotoxic activity of peritoneal exudate cells was found to reside in macrophages. Investigation of the mechanism of macrophage activation by rHuLT revealed that rHuLT can activate macrophages for cytotoxicity synergistically with mouse interferon-gamma. These results strongly suggest that rHuLT, when injected into the tumor, can induce the migration of macrophages into the tumor and activate macrophages in situ to kill tumor cells.

Animals↗