Biomedical subjects

Y Horiguchi

Publications and source records attributed to Y Horiguchi.

At least 127 records · Page 7Linked to original sources

PubMed1993

A case of pretibial dystrophic epidermolysis bullosa: decreased expression of the non-helical domain of type VII collagen molecule.

A 27-year-old man with an ataxic gait due to infantile cerebral paralysis exhibited recurrent blistering caused by mechanical stimuli on the pretibial area of both legs from the age of 20. His parents were not consanguineous, and he had no relatives who suffered from blistering. The histology showed a subepidermal bulla due to dermolytic epidermal-dermal separation. The anchoring fibrils were sparse and rudimentary in the predilection area. An LH 7:2 monoclonal antibody against the non-helical domain of the type VII collagen molecule stained the basement membrane zone of the patient's skin at a weaker intensity than the staining of normal human skin, but at a distinctively stronger intensity than the staining of skin from a patient with recessive dystrophic epidermolysis bullosa. Immunoelectron microscopy revealed that LH 7:2-immunoreactants were distributed irregularly within the lamina densa and sparsely in the sublamina densa region. The patient was diagnosed with pretibial dystrophic epidermolysis bullosa.

Adult↗

PubMed1993

Epidermolysis bullosa acquisita (EBA) with nonclassical distribution of eruptions.

The skin lesions in epidermolysis bullosa acquisita (EBA), a mechanobullous disease, often show acral distribution. Recently, we experienced a case of EBA in which most of the skin lesions were located on the trunk. We reviewed the distribution of the skin eruptions in 58 reported cases of EBA. Although the extensor surfaces of the extremities are the most common site, there were some cases with non-acral distribution. These "nonclassical" cases should also be considered in the clinical diagnosis of EBA and other bullous diseases.

Adult↗

PubMed1993

Stimulation of DNA synthesis in osteoblast-like MC3T3-E1 cells by Bordetella bronchiseptica dermonecrotic toxin.

We investigated the effects of Bordetella bronchiseptica dermonecrotic toxin on DNA synthesis in MC3T3-E1 cells. The rate of [methyl-3H]thymidine incorporation increased in the toxin-treated cells more than 24 h after addition of the toxin under the serum-starved conditions. This effect was dependent on the toxin concentration ranging from 0.3 to 3 ng/ml and was eliminated by aphidicolin and hydroxyurea, inhibitors for DNA replication. In the toxin-treated culture, the number of cells did not increase but polynucleated cells appeared and their number increased to ca. 50% of the total number of cells 6 days after the toxin addition. From these results, we concluded that the toxin stimulates DNA replication in MC3T3-E1 cells without cell proliferation.

Animals↗

PubMed1993

Contribution of plasmin to sex differences in platelet aggregation in the rat.

Platelet aggregation was induced more strongly in male than in female 5, 12, and 45 week-old rats by both collagen and arachidonic acid. This is in agreement with our previous reports which suggested that the sex differences in platelet aggregation may be a primary characteristic of rat platelets. In plasma, plasmin-like activity was higher in male than in female rats. Plasmin alone induced aggregation, and low concentrations of plasmin synergistically enhanced collagen-induced aggregation in both male and female rats. Platelets potentiated plasmin generation by plasminogen activator at various Ca2+ concentrations in both male and female rats. Platelets from males displayed more efficient plasmin generation in 2 mM extracellular Ca2+ than those from females. If platelets were activated by abnormal causes in plasma, generated plasmin could make a greater contribution to the potentiated effect of platelet aggregation in male than in female rats. This study suggests that plasmin may be a partial cofactor in sex differences in platelet aggregation in the rat.

Animals↗

PubMed1993

[Patient-controlled analgesia with epidural pethidine or buprenorphine plus bupivacaine for postoperative analgesia].

We evaluated the efficacy of epidural patient-controlled analgesia (PCA) with pethidine or buprenorphine plus 0.25% bupivacaine for postoperative analgesia after laparotomy with a midline incision under general anesthesia. Twenty patients were randomly allocated to two groups. In one group (PCEA-P group; n = 10), epidural pethidine plus 0.25% bupivacaine by PCA with 5 mg of pethidine and 2.5 ml of 0.25% bupivacaine bolus with a lockout interval of 20 min was added to a continuous epidural infusion of 0.25% bupivacaine (2 ml.h-1) plus pethidine (100 mg.24h-1) for 72 h. In the other group (PCEA-B group; n = 10), epidural buprenorphine plus 0.25% bupivacaine by PCA with 0.03 mg of buprenorphine and 2.5 ml of 0.25% bupivacaine bolus with a lockout interval of 20 min was added to a continuous epidural infusion of 0.25% bupivacaine (2 ml.h-1) and buprenorphine (0.6 mg.24 h-1) for 72 h. Analgesia was evaluated by 100 mm visual analog scale and verbal descriptor scale. In PCEA-B group, 90% of the patients did not complain of pain at rest, and in PCEA-P group, all the patients did not complain of pain at rest for 72 h. There were no significantly different analgesic effects between PCEA-P and PCEA-B for 48 h. The average doses of epidural PCA were 1.9 mg.kg-1.24 h-1 of pethidine, and 0.012 mg.kg-1.24 h-1 of buprenorphine, respectively. We conclude that PCEA-P and PCEA-B were effective for postoperative pain to the same degree for the first 48 h, but PCEA-P was superior to PCEA-B for the last 24 h.

Abdomen↗

PubMed1993

[Spread of spinal anesthesia with 0.5% isobaric bupivacaine].

The effects of age, weight, height, weight.height ratio, and body mass index on the spread of spinal anesthesia with 3.0 ml of 0.5% isobaric bupivacaine was examined in 185 patients. No significant correlation was found between the spread of analgesia and the age, weight, height, weight.height ratio, or body mass index. A significant correlation was found between the decrease in mean arterial pressure and the height of sensory analgesia (rho = -0.21, P < 0.05) as well as the aging (rho = -0.35, P < 0.001).

Adolescent↗

PubMed1993

[Serum nitroglycerin concentrations during extracorporeal circulation with a membrane oxygenator incorporated with a cardiopulmonary bypass circuit].

The effect of a cardiopulmonary bypass circuit (CPB) on serum nitroglycerin (TNG) concentrations was studied in eight patients scheduled for cardiac surgery. The CPB consisted of polyvinyl chloride tubes and polypropyrene membrane oxygenator. TNG was administered intravenously at a rate of 1 microgram.kg-1.min-1 after induction of anesthesia. Blood samples were obtained from the radial artery, central vein, venous inlet of the CPB, and arterial outlet of the CPB. No significant difference in serum TNG concentration was found between the venous inlet of the CPB and arterial outlet of the CPB. Serum TNG concentration tended to increase during complete extracorporeal circulation. This suggests that the hypothermic inhibition of TNG metabolism may be greater than the adsorption of TNG by the CPB.

Adolescent↗

PubMed1993

[Evaluation of the efficacy of a leukocyte depletion filter].

We evaluated the efficacy of a leukocyte depletion filter (Pall RC 100) during operation. Clinically necessary blood was transfused to replace blood loss during the operation. Kinds of transfused blood and speed of transfusion were selected by clinical need. One leukocyte depletion filter was used at most for 4 units of transfused pack (200 ml). Blood samples were taken before and after the filtration to measure white blood cell (WBC), red blood cell (RBC), platelet and hematocrit. Blood samples before filtration and after filtration with white blood cell excluded, were examined by automated hematology analyzer (Coulter counter). White blood cell after filtration was counted by the hemacytometer method using Hauser chamber. The method of multiple linear regression was applied in order to estimate the removal rate of WBC and recovery rate of RBC. The independent variables were categorized in the following 3 sets: the age of transfused blood (day), duration of transfusion (min) and transfused volume (ml). Removal rates of WBC when 1, 2, 3 or 4 units were passed per filter, were 99.99% +/- 0.028%, 99.89% +/- 0.224%, 99.12% +/- 1.519% and 97.81% +/- 2. 866%, respectively. Removal rate of WBC when 4 units were passed per filter, was significantly lower compared with the rate when fewer units were passed. Recovery rates of RBC when 1, 2, 3, or 4 units were passed per filter, were over 99.5%, and there were no significant differences among 4 examined points. Only three variables, the age of transfused blood, duration of transfusion and transfused volume, showed a significant correlation with the removal rate of WBC.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation Studies as Topic↗

PubMed1992

Bordetella bronchiseptica dermonecrotizing toxin suppresses in vivo antibody responses in mice.

The effects of Bordetella bronchiseptica dermonecrotic toxin (DNT) on the in vivo antibody response of mice were investigated. Intravenous injection of DNT at doses of 0.5 and 2.0 ng resulted in a significant suppression of the antibody response both to sheep red blood cells and to Escherichia coli lipopolysaccharide as measured by plaque-forming cell and hemagglutination assays. Spleen weights of mice given the same doses of DNT were significantly reduced, while the weights of thymuses and mesenteric lymph nodes were not. Numbers of Thy-1,2+ T lymphocytes, L3T4+ T lymphocytes, Lyt-2+ T lymphocytes and surface-immunoglobulin-positive lymphocytes decreased in spleens of the DNT-treated mice. Since the ratio of each lymphocyte population to the total number of splenic lymphocytes was not significantly different between the DNT-treated and non-treated mice, it is unlikely that DNT has a cytotoxic activity or a mitogen activity to some specific population of lymphocytes. Thus, we considered that the immunosuppression was attributable to a dysfunction of the spleen atrophied by the DNT.

Animals↗

PubMed1992

Anti-IgM antibody-induced cell death in a human B lymphoma cell line, B104, represents a novel programmed cell death.

We investigated the mechanisms of anti-IgM antibody-induced cell death in a recently established human surface IgM+ IgD+ B lymphoma cell line, B104, the growth of which is irreversibly inhibited by anti-IgM antibody but not by anti-IgD antibody, and compared it with the cell death of T cells via TCR/CD3 complex and with the cell death of a murine anti-IgM antibody-sensitive B lymphoma cell line, WEHI-231. The rapid time course of B104 cell death and its requirements for de novo macromolecular synthesis and Ca2+ influx suggest that anti-IgM antibody-induced B104 cell death is an active Ca(2+)-dependent programmed cell death. Moreover, cyclosporin A rescued B104 cells from this lethal signal, via surface IgM, suggesting that the intracellular mechanisms involved are quite similar to those of T cell death. DNA fragmentation, which has been reported in TCR/CD3 complex-mediated T cell death, apoptosis, was not involved in the B104 cell death process, but the possible involvement of DNA single-strand breaks was suggested. Observations under light microscopy and transmission electron microscopy indicated that the morphologic features of dying B104 cells resembled necrosis rather than apoptosis. B104 cell death was shown to be quite distinct from that of WEHI-231 in cell death kinetics, the mode of cell death, and the response to cyclosporin A. These data collectively indicate that the death of B104 cells resulting from surface IgM cross-linking represents a hitherto undefined mode of programmed cell death.

Antibodies, Anti-Idiotypic↗

PubMed1992

Amyloidosis cutis dyschromica. DNA repair reduction in the cellular response to UV light.

BACKGROUND: Amyloidosis cutis dyschromica, a special type of primary cutaneous amyloidosis, is assumed to be a congenital disorder and sun exposure is thought to be the major causal factor. Herein we report a case of this rare disease and DNA repair characteristics of UV damages in the fibroblasts derived from the patient. OBSERVATIONS: A 24-year-old Japanese woman showed hyperpigmented and hypopigmented xerotic lesions in sun-exposed skin since she was 10 years old; deposits of amyloid material were detected in the papillary dermis. The fibroblasts were hypersensitive to UV-B, but not so sensitive to UV-C. Unscheduled DNA synthesis of the patient's cells after UV-C exposure was lower than that of normal cells at 3 hours and both reached the same level at 6 hours. After UV-B exposure, unscheduled DNA synthesis of the patient's cells was lower than that of normal cells at least until 6 hours after UV exposure. CONCLUSION: Although the origin of amyloidosis cutis dyschromica is unknown, hypersensitivity to UV-B with possible DNA repair defects is suggested to be the cause of this disease.

Adult↗

PubMed1992

Expression of cadherin cell adhesion molecules during human skin development: morphogenesis of epidermis, hair follicles and eccrine sweat ducts.

Expression of E (epithelia) and P (placental) cadherin cell adhesion molecules was examined immunohistochemically using human developing skin. In adult skin, E-cadherin was expressed on cell surfaces of whole epidermal layers including skin appendages, whereas P-cadherin was expressed only on those of basal layers and the outer layers of skin appendages, which was consistent with the compartment of proliferating cells. In fetal skin, while the patterns of E- and P-cadherin expression were generally similar to those in the adult, P-cadherin temporarily showed a unique spatiotemporal expression pattern in developing sweat ducts. During this stage, the expression of P-cadherin accumulated in the epidermal ridges and showed a discrepancy with the compartment of proliferating cells. These results suggest that the expression of P-cadherin is spatiotemporally controlled, and may be closely related to the segregation of basal layers as well as to the arrangement of epidermal cells into eccrine sweat ducts, but is not closely related to cell proliferation.

Adult↗

PubMed1992

Assessment of chemoembolization therapy for primary liver cancer using a stabilized adriamycin-lipiodol suspension.

We formulated a new lipiodol-Adriamycin suspension (ADM/lipiodol, 50 mg/10 ml) that remained stable for 48 h (half-life, 25 +/- 3 days). In five cases of hepatocellular carcinoma (HCC) resected after intra-arterial infusion of this agent, the ADM concentration in the tumor was quite high and the tumor necrosis rate was more than 80% on histological examination. Over a 5-year period, 180 patients with unresectable HCC underwent transcatheter arterial embolization therapy (TAE) in the presence or absence of this agent. The regimens consisted of suspension injection alone (A, n = 54), suspension injection + TAE using gelatin sponge (B, n = 29), TAE followed by suspension injection (C, n = 34), and TAE alone (D, n = 63). The estimated 1-year survival values determined for patients treated with these regimens were 70%, 73%, 43%, and 39% respectively, and the corresponding 3-year survival values were 27%, 31%, 15%, and 10%. The survival achieved using suspension injection was thus superior to that obtained using conventional TAE, and combined therapy with suspension injection followed by TAE seemed to enhance survival, although there were some biases in tumor size and in the stage of tumor progression. For patients with tumors measuring 5 cm or more in diameter, the survival obtained using regimen A was lower than that achieved using regimen D, but the combination of TAE and suspension injection improved the 1-year survival value obtained using regimen D from 34% to 52%. For patients with tumors measuring less than 5 cm in diameter, the survival achieved using regimen A was markedly better than that obtained using regimen D, although no difference was found between the survival value achieved using regimen A and that obtained using regimens B and C. On the basis of these results, our newly formulated ADM-lipiodol suspension was surmised to be effective by itself against relatively small HCC tumors, whereas it enhanced the efficacy of conventional TAE in large lesions.

Aged↗

PubMed1992

Inhibition of neuromuscular transmission in isolated mouse phrenic nerve-diaphragm by the enterotoxin of Clostridium perfringens type A.

The enterotoxin of Clostridium perfringens type A, a channel forming protein toxin, inhibited neuromuscular transmission under conditions of low calcium. Twitch tension of isolated phrenic nerve-diaphragm preparations elicited by electrical stimulations to the phrenic nerve was recorded isometrically, and the preparations were exposed to the purified enterotoxin. In Krebs solution containing 0.5 mM calcium, the enterotoxin (20 micrograms/ml) reduced within 10 min the amplitude of the twitch tension to 34 +/- 7% (mean +/- S.D., n = 11) of that recorded before the treatment. The effects of the enterotoxin on the twitch tension were irreversible and proceeded independently of stimulation. The reduction of the twitch tension by the enterotoxin was apparent in Krebs solution containing less than 0.6 mM calcium and the degree of reduction was inversely related to the concentration of calcium. The reduction of the twitch tension by the enterotoxin was also dependent on temperature and concentration of the toxin. At temperatures below 20 degrees C, no obvious reduction of twitch tension was observed with 20 micrograms/ml of the enterotoxin. Enterotoxin at a concentration of 0.4 micrograms/ml caused 16 +/- 2% (mean +/- S.D., n = 4) reduction of twitch tension, and the degree of the reduction in twitch tension increased with toxin concentration, reaching a plateau of 65 +/- 4% (mean +/- S.D., n = 7) at 6.5 micrograms/ml of the enterotoxin. The effects of the enterotoxin were antagonized by 2 microM physostigmine. Unlike curare, pretreatment of the preparation with enterotoxin did not antagonize the neuromuscular block by decamethonium. Neither the tension of muscular twitch elicited by direct electrical stimulation to the muscle nor the resting membrane potentials of muscle fibers recorded intracellularly were affected by the enterotoxin. The enterotoxin (2.2 micrograms/ml) reduced the frequency, but not mean amplitude or amplitude distribution, of miniature end-plate potentials, from 0.91 +/- 0.07/sec to 0.72 +/- 0.07 (mean +/- S.E., n = 5). The results suggest that the enterotoxin will provide a novel tool for the studies on the mechanism of the neuromuscular transmission because of the unique characteristics of the inhibition and of the known mechanism of its action on the cell membrane.

Animals↗

PubMed1992

Altered distribution of 1-2B7B antigen in basal cell carcinoma, squamous cell carcinoma and Bowen's disease.

Skin lesions of basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and Bowen's disease were immunohistochemically examined using the 1-2B7B monoclonal antibody, which recognizes a 120 kDa polypeptide component found in hemidesmosomes of normal human epidermis and hemidesmosome-like adhesion junction of vascular endothelial cells, to disclose altered characteristics of the interface between the tumor cell aggregate and stromal tissues of the epidermal neoplasms. In BCC, 1-2B7B antigen was rarely expressed at the tumor cell aggregate-stromal tissue interface, where poorly developed hemidesmosometonofibril complexes and a normal-looking lamina densa were detectable. In SCC and Bowen's disease, 1-2B7B antigen was expressed not only along the interface of the tumor nest and stromal tissue, but also in the intercellular space of the desmosomes and other adhesion junction structures that lack associating tonofibrils. In the invading front of SCC, 1-2B7B antigen had partly disappeared from the tumor cell aggregate-stromal tissue interface, where neither hemidesmosomes nor lamina densa were noted. The altered distribution of this hemidesmosomal component in the epidermal neoplasms seems to reflect aberrant interaction of neoplasmic cells and surrounding stromal tissue.

Antibodies, Monoclonal↗

PubMed1992

Incidence and natural course of trabecular ventricular septal defect: two-dimensional echocardiography and color Doppler flow imaging study.

This study was designed to determine the prevalence of trabecular ventricular septal defect (t-VSD) in neonates and to evaluate the effects of its location, morphologic features, and size on its natural course during infancy. One thousand twenty-eight term newborn infants were examined by color Doppler flow imaging with orthogonal ultrasonographic views. Ten girls and 11 boys (2.0%) were found to have t-VSD. The natural course of the defect was examined in 42 consecutive cases, consisting of this group of 21 neonates and another group of 21 neonates with t-VSD. The morphologic features of the defect within the trabecular septum were classified as one or two defects (36 cases) and as a mesh-like defect (six cases). Reduction in size began from the right ventricular side or from within the trabecular septum. Spontaneous closure occurred most commonly during the first 6 months of life and was observed in 32 cases (76%) by 12 months of age: the frequency of closure was not related to the morphologic features and the initial size of the defect, but apical defects tended to have higher persistent patency than did defects in other locations (p less than 0.05). We conclude that the frequency of t-VSD in neonates and the frequency of spontaneous closure during early infancy are higher than previously believed. This information is important for predicting the natural course of t-VSD and deciding on its proper management.

Blood Flow Velocity↗

PubMed1992

Lamina densa malformation involved in histogenesis of primary localized cutaneous amyloidosis.

Skin lesions of lichenoid amyloidosis and macular amyloidosis were immunohistochemically investigated using five monoclonal antibodies against basement membrane zone (BMZ) components. A hemidesmosomal component did not contribute to amyloid deposits, but components of the lamina densa and anchoring fibrils were associated with amyloid deposits in the uppermost dermis. Immunoelectron microscopy revealed that these BMZ components were not only aggregated in the BMZ and dermis, but were also involved in the individual amyloid islets. The lamina densa was disrupted in the interface areas just above the amyloid deposits, where cytoplasm of the basal cells directly faced the aggregate of amyloid filaments. Aggregates of some BMZ components were continuous to the amyloid islets from the lamina densa area. These findings suggest that a lamina densa malformation is involved in amyloid production in the interface of the BMZ, and support the secretion theory rather than the fibrillar body theory of amyloidogenesis in these types of primary localized cutaneous amyloidosis.

Amyloid↗

PubMed1992

The ultrastructural histopathology of eosinophilic pustular folliculitis.

The follicular skin lesions of a patient with eosinophilic pustular folliculitis were investigated by electron microscopy. Pustules in the outer root sheath contained acantholytic keratinocytes with numerous microvilli and features of desmosomal cleavage. The infiltrating eosinophils and neutrophils exhibited autolytic or degenerative changes rather than degranulation. The aggregated tubulo-vesicular structures were associated with the debris of autolytic eosinophils. Multiple, tiny, bubble-like structures enclosed within a membrane were frequently seen in the intercellular space. The intercellular space of the outer root sheath was widened with decreased desmosomal adhesion between the keratinocytes, but no intracellular edema was detectable. The infiltrating lymphocytes, predominantly T-cells with convoluted nuclei, extended cytoplasmic processes to adjacent keratinocytes. Apposition of T-lymphocytes and Langerhans cells was noted. Some keratinocytes in the outer root sheath contained large, sebaceous lipid droplets. No obvious virus particles or other pathogenic agents were detected. It is possible that T-lymphocytes and other immunosurveillance cells are involved in the pathomechanism of eosinophilic pustular folliculitis.

Adult↗