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Biomedical subjects

M Nagashima

Publications and source records attributed to M Nagashima.

At least 271 records · Page 15Linked to original sources

Cardiac arrhythmias in healthy children revealed by 24-hour ambulatory ECG monitoring.

Ambulatory electrocardiographic monitoring was performed on 360 healthy children, from newborn infants to junior high school students. They were divided into five groups by age: group A, 63 newborn infants on the first day of life; group B, 50 infants aged 1-11 months; group C, 53 kindergarten pupils aged 4-6 years; group D, 97 primary school pupils aged 9-12 years; and group E, 97 junior high school students aged 13-15 years. The maximal and minimal heart rates were significantly greater in infants than in older children. Sinus arrhythmia was recorded in every child. One boy in group E had an episode of sinus arrest for three seconds without any symptoms. First-degree and Wenckebach type second-degree atrioventricular blocks were not detected in group A and group B, but were most frequent in group E, especially during sleep. Supraventricular premature contractions (SVPCs) were the most common type of arrhythmia detected in this study. More than half of the children had at least one SVPC per 24-h monitoring period, and there were many children with frequent SVPCs in group E. The incidence of ventricular premature contractions (VPCs) in children of groups A and E was rather higher than in the other groups. Ventricular tachycardia was not recorded in any child except one newborn infant who had a couplet of VPCs without symptoms. Each group had different types and incidences of arrhythmias. There was a rising incidence of arrhythmias with advancing age, except in the neonatal period.

Adolescent↗

High-dose gammaglobulin therapy for Kawasaki disease.

To evaluate the effectiveness of gammaglobulin in decreasing the incidence of coronary artery lesions in Kawasaki disease, a randomized controlled study in 136 patients was conducted using high doses of gammaglobulin 400 mg/kg/d for 3 days plus aspirin 30 mg/kg/d (gammaglobulin group) and aspirin alone at the same dosage (aspirin group). The total febrile period and the duration of fever after treatment were significantly shorter in the gammaglobulin group than in the aspirin group (P less than 0.001). The incidence of coronary artery lesions and of coronary artery aneurysms was significantly lower in the gammaglobulin group than in the aspirin group up to 30 days after the onset of Kawasaki disease (P less than 0.01 and P less than 0.05, respectively). In 16 of 69 patients given gammaglobulin, fever persisted for longer than 3 days, and there was a higher incidence of coronary artery lesions among them. The effectiveness of high doses of gammaglobulin in preventing coronary artery lesions has been demonstrated, but the indications and the optimal dose of gammaglobulin remain to be determined.

Aspirin↗

Induction of cutaneous graft-versus-host disease by allo- or self-Ia-reactive helper T cells in mice.

Recent evidence suggests that Ia+ Langerhans cells may be a primary target for destruction in cutaneous graft-versus-host disease (GVHD). Although it is generally accepted that T lymphocytes with helper/inducer phenotype are essential, the identity of the effector cells is still controversial. We therefore investigated whether a variety of Ia-reactive cloned helper T cells with different cross-reactivities and functions in vitro can induce cutaneous GVHD following intradermal inoculation into the footpad of the appropriate recipients, whose Ia antigens are able to stimulate the T cells to proliferate in vitro. All cloned T cells tested caused significant footpad swelling in their appropriate recipients with a course typical for local cutaneous delayed-type hypersensitivity (DTH) reactions. Two of these cloned T cells, SK 1 and BB5, induced local histologic changes consistent with grades 2-3 of cutaneous GVHD in the appropriate allogeneic or syngeneic recipients at 48-72 hr after their intradermal inoculation. Immunohistochemical studies using monoclonal antibodies demonstrated that not only injected cloned T cells but also Lyt-1+ cells derived from the recipient migrate into the epidermis and are responsible for the destruction seen in cutaneous GVHD. In epidermis in which cutaneous GVHD had been induced, expression of Ia by keratinocytes and the damage of Ia+LC were observed. These results suggest that Ia+LC and Ia+ keratinocytes may play an important role in the infiltration of Ia-reactive T cells responsible for cutaneous GVHD.

Animals↗

The effect of short-lasting atrial pacing on the release of atrial natriuretic peptide, vasopressin, and methionine enkephalin in man.

In order to study the effect of atrial tachycardia on the release of atrial natriuretic peptide (ANP), AVP, and methionine enkephalin (M-Enk), plasma concentrations of these peptides in the right ventricle were determined in patients with various arrhythmias (N = 10) during cardiac catheterization and incremental atrial pacing. Each pacing (100 per min, the maximum rate for 1:1 atrioventricular conduction, and 200 per min) lasted 4 to 5 min. Plasma ANP was significantly increased from 53.1 +/- 12.2 in the resting condition to 168.9 +/- 59.9 pmol/l at a pacing rate of 200 beats per min (P less than 0.05); plasma AVP tended to decrease, but not significantly, and plasma M-Enk did not change at all. Pulse pressure in the right atrium (PPRA) and mean right atrial pressure (MRAP) tended to increase during the pacing, and at the rate of 200 beats per min PPRA was significantly higher than at the rate of 100 beats per min. Mean arterial blood pressure, plasma osmolality, and plasma sodium and potassium concentrations did not change significantly. There were significant correlations between plasma ANP and PPRA, MRAP and heart rate. These results indicate that atrial pacing stimulates ANP release with a rise in right atrial pressure, but does not influence M-Enk and AVP releases.

Adult↗

Study on congenital complete heart block in children by 24-hour ambulatory electrocardiographic monitoring.

Ambulatory electrocardiographic monitoring was performed in 18 children with a congenital complete heart block (CCHB). They had no cardiac structural anomalies. These patients could be divided into 3 groups according to the pattern of fluctuations in beat-to-beat ventricular rates. Type 1 patients showed rapid and transient fluctuations and demonstrated a high correlation between atrial and ventricular rates. Type 3 patients showed a constant ventricular rate and little variation through the 24 hour period and there was no appreciable correlation between atrial and ventricular rates. Twelve of 18 patients had additional arrhythmias. A few sporadic ventricular premature contractions (VPCs) were found in 9 patients, and bigeminy of VPCs or ventricular tachycardias were seen in 2 patients during exercise. Frequent and sudden prolongation of RR intervals was found during sleep in 3 patients. The longest intervals of ventricular asystoles were 7.2, 3.2 and 3.2 sec, respectively. The mechanism of this phenomenon appeared to be not only an exit block, but also arrest or a lack of automaticity of a subsidiary pacemaker. One of these patients developed frequent Stokes-Adams attacks. Type 3 patients with sudden prolongation of RR intervals and/or frequent ventricular arrhythmias should be under careful observation. Ambulatory electrocardiographic monitoring is recommended for children with CCHB for evaluation of potential risk factors for Stokes-Adams attacks.

Adolescent↗

Lichenoid tissue reaction (LTR) induced by local transfer of Ia-reactive T-cell clones. II. LTR by epidermal invasion of cytotoxic lymphokine-producing autoreactive T cells.

Recent studies have suggested that T lymphocytes with helper phenotype may play an important role in the pathogenesis of lichenoid tissue reactions (LTR). In order to elucidate whether murine self-Ia-specific autoreactive T cells with helper phenotype can induce LTR in naive syngeneic hosts, two clones of autoreactive cloned T cells with both helper and cytotoxic activities, capable of producing the cytotoxic lymphokines gamma interferon and lymphotoxin in response to self-Ia antigens, were examined for their ability to induce LTR. One clone, BB5, when injected into footpads of syngeneic hosts, induced prominent epidermotropic cellular infiltrates that led to basal vacuolar degeneration and Civatte body formation; the other clone, C10, did not. No difference between BB5 and C10 was detected with respect to their ability to induce delayed-type hypersensitivity reactions. Immunohistochemical studies using anti-Lyt monoclonal antibodies showed that BB5-induced LTR was induced by the epidermal invasion of the injected BB5 cells themselves. We further observed that the infusion of BB5 cells not only resulted in Ia antigen expression on keratinocytes, but was also accompanied by a morphologic change in Langerhans cells at 24 h, when the epidermal invasion had not yet developed. However, similar observations were also observed with C10 cells, indicating that Ia expression on keratinocytes may not be a prerequisite for the induction of LTR.

Animals↗

Production of interleukin-2 and interleukin-2 inhibitor in patients with palmoplantar pustulosis.

We studied production of interleukin-2 (IL-2) and IL-2 inhibitor from peripheral blood of patients with palmoplantar pustulosis (PPP). Nineteen patients were divided into two groups: those with and those without arthro-osteitis. Although IL-2 production in both groups of patients was within normal limits, those with arthro-osteitis showed greater fluctuation in relation to the disease activity. The IL-2 production of five PPP patients with arthro-osteitis was greatly enhanced in the inactive stage compared with the active stage. Sera from two patients treated with a combination of etretinate and colchicine contained extremely low levels of IL-2 inhibitory activity. The increased IL-2 production in the inactive stage may be due in part to the depletion of IL-2 inhibitor-producing cells by the treatment.

Adult↗

[Application of digital subtraction angiography (DSA) in the neurosurgical field].

Intraarterial digital subtraction angiography (DSA) was applied 44 times to 39 neurosurgical cases. We emphasize the advantage of DSA in relation to conventional angiography. The examination consisted of 25 aortography and 19 selective arteriography. By single small dose injection of contrast medium using DSA, aortic arch and thoracic major vessels were well visualized, so that we could obtain useful information for catheterization to the selective artery. High time resolution of DSA made possible to recognize dynamics of circulation in very short interval, especially in the case of subclavian steal syndrome and right aortic arch. Major four vessels in the cervical region could be visualized by single injection of contrast medium using DSA. Stenosis of carotid artery was recognized by DSA as well as conventional angiography. By aortic injection using DSA, circulatory dynamics of intracranial vessels including collateral circulation were recognized especially in the case of moyamoya disease. Gradual injection of small dose contrast medium reduced jet-effect of the catheter tip and enabled the selective arteriography. Real time display of DSA reduced the time required for examination and enabled repeated angiography to recognize the change of hemodynamics under the different limb position in the case of thoracic outlet syndrome.

Cerebral Angiography↗

[Diagnostic value of digital subtraction angiography (DSA) using Toshiba Digiformer X in the cerebrospinal vascular diseases].

Using TOSHIBA Digiformer X, digital subtraction angiography (DSA) was performed in 286 patients, in whom 229 patients of cerebro-spinal vascular disease was included. The authors emphasize the usefulness of DSA in cerebro-spinal vascular disease in relation to conventional angiography. DSA taken by single small dose injection of contrast medium into the ascending aorta clearly demonstrates not only aortic arch and thoracic major vessels, but also cervical vessels and all intracranial vessels. Therefore, we could rapidly understand gross dynamics of the circulation and obtain useful informations prior to catheterization to the selective artery. This advantage of DSA was particularly useful for occlusive vascular diseases. Gradual injection of small dose of contrast medium obviously reduced recoiling of the catheter tip, which enabled the selective angiography with setting of the tip of the catheter at the entrance of cervical major vessels without its sufficient insertion into the selective vessels. This advantage is particularly beneficial for the patients with severe arteriosclerosis who was found to be difficult for selective catheterization. In our experience, demonstration of a presence of aneurysm by DSA was possible in almost all cases of subarachnoid hemorrhage, although spatial resolution of DSA is said to be inferior to the conventional angiography. Real time display of DSA decreased the time required for examination and enabled repeated angiography. This advantage of DSA is especially useful for the patients with spinal arterio-venous malformation and thoracic outlet syndrome.

Cerebral Angiography↗

[Extramedullary plasmacytoma forming a mass in the epidural space of the spinal cord: report of a case].

Plasmacytoma often forms an intramedullary mass in the vertebrae with absorption of trabecula and cortex of the bone. However, occasionally, it forms a mass in the extramedullary space of the vertebrae. The authors report such a rare case with plasmacytoma which formed a mass in the thoracic epidural space without evidence of involvement of the adjacent vertebra. On May 22, 1985, a 80-year-old man was admitted to our clinic with chief complaints of gait disturbance and hypesthesia below the umbilical level. Difficulty of walking developed approximately four months prior to admission with gradual aggravation and hypesthesia added thereafter. Neurological examinations at admission showed paraparesis with positive Babinski's and Chaddock's reflexes, hypesthesia and disturbances of vibration and position senses below the 9th thoracic nerve level. Myelography and CT scan using metrizamide indicated a presence of epidural mass at the 8th to 9th thoracic vertebrae. There was no abnormal bony change in the spine on plain X-ray and CT scan. On May 30, 1985, total removal of epidural tumor was performed by removing the laminae from the 7th to 10th vertebrae. Histological examinations including immunological stainings showed a plasmacytoma which produced monoclonal immunoglobulin of IgG-lambda type. Radiation therapy was not carried out. The serum protein fraction, immunoglobulin, immunoelectrophoresis, Bence-Jones protein and CSF immunoglobulin examined after operation, supported a histological diagnosis of plasmacytoma. Also, slight proliferation of plasma cells was noted in the bone marrow and peripheral blood.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Cloned auto-Ia-reactive T cells elicit lichen planus-like lesion in the skin of syngeneic mice.

To explore the physiologic or pathologic roles of autoreactive T cells, we examined immunological functions of several autoreactive mouse T cell clones in vitro and in vivo. All of the T cell clones were Lyt-2-, L3T4+ and showed self-I region-restricted proliferative responses (one clone was self-I-E restricted, the other clones were self-I-A restricted). One clone derived from C57BL/6 mouse and reactive to the self-I-Ab product (clone bb1-2) showed cross-reactivity to the I-Ak product. Among four such auto-Ia-reactive T cell clones examined, one clone produced fairly large amounts of interleukin 2 (IL 2) in response to syngeneic stimulator cells, and mediated help for the in vitro cytotoxic T cell (CTL) responses of syngeneic thymocytes, whereas this clone did not mediate in vitro antibody responses of syngeneic B cells. The other three clones were producers of small amounts of IL 2 and did not mediate the in vitro CTL responses. Among the three clones, clone bb1-2 showed strong regulatory function, and clone kk-1 (B10.BR origin and self-I-Ak reactive) showed weak regulatory function in vitro antibody responses of syngeneic B cells. The physiologic or pathologic roles of autoreactive T cells in vivo were explored by injecting subcutaneously clone kk-1 T cells or clone bb1-2 T cells into the footpads of the respective syngeneic mice. Clone kk-1 T cells injected into syngeneic mice elicited swelling of the footpad and marked accumulation of mononuclear cells in the dermis, leaving the epidermis intact, as in the delayed-type hypersensitivity reaction. As a notable finding, clone bb1-2 T cells injected into syngeneic mice elicited marked swelling of the footpad and lichen planus-like skin lesions, i.e., infiltration of lymphocytes in the epidermis and epidermal cell damage. The lymphocytes infiltrating in the epidermis were evaluated, as were the injected clone bb1-2 T cells expressing the Lyt-1.2 phenotype, by examination of the skin lesions elicited in C3H/He mice (H-2k, Lyt-1.1, 2.1) by the clone T cells. Clone bb1-2 T cells exerted in vitro cytotoxicity against H-2b and H-2k target cells, whereas clone kk-1 T cells did not show any cytotoxic activity, indicating a correlation between the cytotoxic activity of clone bb1-2 T cells and their ability to elicit lichen planus-like lesions.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

In-vitro antibacterial activity of BO-1165, a new monobactam antibiotic.

BO-1165 has excellent antibacterial activity against Gram-negative bacteria but it is almost inactive against Gram-positive and anaerobic bacteria. BO-1165 was more active than the four reference drugs against Escherichia coli, Salmonella spp., Shigella spp., Klebsiella pneumoniae, Serratia marcescens, indole-positive and indole-negative Proteus. Also, BO-1165 exhibited high antibacterial activity against strains of Pseudomonas aeruginosa (MIC50, 3.12 mg/l) and P. cepacia (MIC50, 1.56 mg/l), but did not against Ps. maltophilia strains. BO-1165 had good stability to plasmid-mediated and chromosome-mediated beta-lactamases. However, the compound was slightly hydrolyzed by the beta-lactamases isolated from Proteus vulgaris, Ps. cepacia, Klebsiella oxytoca and Ps. maltophilia, which were capable of hydrolyzing aztreonam.

Aztreonam↗

Lichenoid tissue reaction induced by local transfer of Ia-reactive T-cell clones.

Epidermal basal cell damage in lichenoid tissue reactions (LTR) is considered to be the result of immunologic injury. In this study, we propose that LTR may be caused by local activation of Ia-reactive T cells. We have established allo-Iak-reactive helper T-cell clones and examined their behavior after adoptive transfer. We show that local transfer of 3 allo-Iak-reactive helper T-cell clones with different cross-reactivities and functions in vitro can cause delayed type hypersensitivity (DTH) reactions in vivo with antigen specificities identical to those demonstrated in vitro. Clone SK.1, when injected into appropriate recipients, caused massive dermal infiltrates of neutrophils and mononuclear cells. The latter were attracted to the epidermis and induced LTR-like basal cell degeneration which peaked at 72 h. Appropriate recipients were those strains of mice whose spleen cells were able to stimulate SK.1 cells to proliferate in vitro. Two other clones, SK.2.18 and SK.2.16, evoked significant DTH responses in their appropriate recipients, but the massive cellular infiltrates induced by either clone never invaded the epidermis or produced an LTR. The degeneration of epidermal cells caused by SK.1 cells did not correlate with the tested functions of this clone in vitro. The finding that only 1 of the 3 allo-Ia-reactive helper T-cell clones induced epidermotropic cellular infiltrates indicates that the infiltrative pattern of leukocytes in skin may depend on the particular T-cell clone that is activated.

Animals↗

Intrauterine supraventricular tachyarrhythmias and transplacental digitalisation.

Six newborn infants with intrauterine supraventricular tachyarrhythmias (five cases of atrial flutter and one of supraventricular tachycardia) are described. Transplacental digitalisation was attempted in three cases. Supraventricular tachycardia associated with hydrops fetalis, detected in a fetus at a gestation of 31 weeks, was successfully converted to normal sinus rhythm eight days after the mother began treatment with digoxin. The serum concentration of digoxin in cord blood almost equalled the maternal concentration in three cases. In the remaining three cases treatment with digitalis was effective in converting tachyarrhythmias to sinus rhythm after delivery. With maintenance digoxin therapy, the prognosis of fetal tachyarrhythmias seems to be good, once conversion to sinus rhythm has been accomplished.

Atrial Flutter↗

Amino acid sequence of rat apolipoprotein A-II deduced from the nucleotide sequence of cloned cDNA.

A rat apolipoprotein A-II cDNA clone was isolated from a rat liver cDNA library by in situ hybridization of bacteriophage plaques using a 32P-labeled human apoA-II cDNA as a probe. The cDNA insert from this clone was characterized by DNA sequencing. The amino acid composition derived from the DNA sequence data matched well with that of rat apoA-II reported earlier (Herbert et al. 1974. J. Biol Chem. 249: 5718-5724), indicating that the cDNA insert coded for rat apoA-II. Further evidence was provided by a comparison of the amino acid sequence of rat apoA-II obtained here with that of human apoA-II (Brewer et al. 1972. Proc. Natl. Acad. Sci. USA. 69: 1304-1308). While the rat apoA-II cDNA insert did not code for the entire presegment, it had the same COOH-terminal residues of the presegment as well as the same prosegment (Ala-Leu-Val-Arg-Arg) as in human preproapoA-II, suggesting that rat apoA-II was also synthesized initially as preproapoA-II. Mature rat apoA-II contains 79 amino acids. Residue 6 of mature rat apoA-II is Asp, while it is Cys in human apoA-II, and this would account for the absence of dimeric forms of rat apoA-II in plasma. While the overall amino acid sequence homology between rat and human apoA-II is about 50%, the amphipathic alpha-helical structures, which are responsible for lipid-binding, seem to be conserved in the two proteins. The size of rat apoA-II mRNA was estimated to be about 600 nucleotides.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗