Biomedical subjects

M Iijima

Publications and source records attributed to M Iijima.

At least 181 records · Page 10Linked to original sources

PubMed1990

Hypotensive and hemodynamic effects of the new non-sulfhydryl angiotensin converting enzyme inhibitor N-[8-amino-1(S)-carboxyoctyl]-L-alanyl-L-proline.

The hypotensive effects of N-[8-amino-1(S)-carboxyoctyl] -L-alanyl-L-proline (AB-47, CAS 120008-53-9) were examined in normotensive rats and various hypertensive rat models. The hemodynamic effect of AB-47 was also examined in anesthetized spontaneously hypertensive rats (SHR). In 2-kidney, 1-clip renal hypertensive rats (2K, 1C-RHR) and SHR, the single administration of AB-47 (10 mg/kg, p.o.) induced potent and long-lasting hypotensive effects. The repeated administration of AB-47 (1 to 10 mg/kg, p.o.) to SHR for 29 days produced a dose-dependently and sustained hypotensive effect of 20 to 70 mmHg. AB-47 (10 mg/kg, p.o.) had a weak hypotensive effect in DOCA-salt hypertensive rats but no effects in normotensive and 1-kidney, 1-clip renal hypertensive rats (1K, 1C-RHR). AB-47 (3 mg/kg, p.o.) reduced blood pressure in intact SHR but not in bilateral nephrectomized SHR. The single intravenous injection of AB-47 (10 to 100 micrograms/kg) dose-dependently lowered systemic blood pressure, left ventricular systolic pressure (LVSP) and dp/dtmax without affecting heart rate (HR) and these effects of AB-47 were more potent than those of captopril and enalaprilat. These results suggest that AB-47 is a potent and long-lasting hypotensive agent and may be useful for the therapy of both hypertension and congestive heart failure.

Administration, Oral↗

PubMed1990

[Weibull statistical analysis of bending strength data measured either in air or in distilled water for sintered hydroxyapatite ceramics coated on the metal substrate].

To assess the effects of H2O on the fracture stress of sintered hydroxyapatite (HAP) ceramics prepared by procedures similar to those used for HAP coated on the metal substrate, four-point bending tests were carried out at 0.5 mm/min either in air (20 C, R.H. 73%) or in distilled water (37 degrees C). Then, strength data obtained were analyzed using two-parameter weibull statistics. In each condition, the bending strength data gave a good fit to single-mode weibull distribution. Weibull analysis of the data gave weibull parameter m = 7.8, sigma 0 = 26.2 MPa in air and m = 8.1, sigma 0 = 18.5 MPa in distilled water, which were calculated assuming a surface flaw model. The mean value of bending strength was 27.3 MPa in air and 18.2 MPa in distilled water. These results indicated that a corrosive environment such as H2O affects fracture stress when measured at a constant stress rate. This effect is considered to be caused by slow crack growth of cracks, occurring at a loading level lower than those at which specimens will fail. Using the weibull distribution function estimated in this study, the effects of both dimension of specimen and stress distribution in the specimen on the mean fracture stress have been predicted.

Air↗

PubMed1990

[Estimation of fatigue parameter and life-time prediction using SPT diagram for hydroxyapatite coating layer in 37 degrees C distilled water].

Lifetime and survival probability of brittle materials under given conditions of stress distribution, environment and component size can be predicted using an SPT (Strenght-Probability-Time) diagram. The SPT diagram for sintered hydroxyapatite (HAP) coated on the metal substrate via the fused glass was drawn and the safe working stress in 37 degrees C distilled water was estimated. The dynamic fatigue test carried out in 37 degrees C distilled water gave the fatigue parameter n = 19 for sintered HAP. This parameter is constant except that it depends on material and environment, and the greater the value of n, the greater the resistance to fatigue failure. For sintered HAP, therefore, the resistance to fatigue failure under this wet condition is low. To draw the SPT diagram, anchor points were taken from the fracture stress and time-to-failure data measured at 1 mm/min. The SPT diagram obtained suggested that a lifetime of 20 years with survival probability of 99.9% required the safe working stress of less than 3.2 MPa. The effects of accuracy of fatigue parameter on the uncertainty in SPT diagram were estimated.

Corrosion↗

PubMed1990

Synthesis and angiotensin converting enzyme inhibitory activity of N-carboxymethyldipeptides with omega-(4-piperidyl)alkyl group.

The synthesis of a series of novel, potent angiotensin converting enzyme (ACE) inhibitors containing 1(S)-carboxy-omega-(4-piperidyl)alkyl group at the N-terminal of the dipeptide is described. These 1-carboxy-omega-(4-piperidyl)alkyl derivatives possess greater or equivalent in vitro potency and in vivo efficacy than captopril and enalapril. The length (n) of the carbon chain in the omega-(4-piperidyl)alkyl moiety was varied from two to six to investigate the optimal structure for long-acting ACE inhibitors. 1-[N-[1(S)-Carboxy-6-(4- piperidyl)hexyl]-L-alanyl]-(2a,3a beta, 7a beta)-octahydro- 1H-indole-2-carboxylic acid (9b), the most potent member of the series, had an in vivo area under the curve (AUC) of 685, which was calculated by the inhibition of angiotensin I-induced pressor response vs. time curves (0 to 8 h) after p.o. administration.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1990

Pharmacological properties of the new non-sulfhydryl angiotensin converting enzyme inhibitor N-[8-amino-1(S)-carboxyoctyl]-L-alanyl-L-proline.

AB-47 (N-[8-amino-1(S)-carboxyoctyl]-L-alanyl-L-proline) is a non-sulfhydryl angiotensin converting enzyme (ACE) inhibitor with omega-aminoalkyl group. AB-47 was slightly more potent than enalaprilat in inhibiting rabbit lung ACE. The ACE inhibition and bradykinin (BK) potentiation by AB-47 in guinea-pig ileal longitudinal muscle were as potent as with enalaprilat. In conscious rat, AB-47 (i.v.) inhibited angiotensin I (A-I)-induced pressor response and augmented BK-induced depressor response more potently and in a long-lasting manner than enalaprilat. Furthermore, AB-47 exhibited higher selectivity for ACE inhibition than for BK inactivation and higher selectivity than enalaprilat and captopril. The inhibition of A-I-induced pressor response by AB-47 (p.o.) was as potent as that of enalapril. These results suggest that AB-47 is a highly potent, long-lasting and relatively A-I-selective ACE inhibitor.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1990

[A case of inorganic germanium poisoning with peripheral and cranial neuropathy, myopathy and autonomic dysfunction].

A 51-year-old man, taking beverage containing inorganic germanium (Ge), (90-100 mg/day, total 70 g) for two years, developed body weight loss, anemia, renal dysfunction, peripheral neuropathy, myopathy, autonomic dysfunctions and multiple cranial nerve palsies. Serum CK, GOT, LDH, BUN, and creatinine levels were elevated. The cerebrospinal fluid showed albumino-cytologic dissociation. Sural nerve biopsy showed axonal degeneration, and peroneal muscle biopsy showed neurogenic changes including type 2 fiber atrophy and ragged red fibers. High level of Ge content was detected from the hair and nail by inductively coupled plasma atomic emission spectrometry. Despite discontinuation of Ge taking, the peripheral neuropathy and autonomic dysfunction progressed. The symptoms remained unchanged even in the treatment with prednisolone. These findings suggest that inorganic Ge has a serious irreversible multiple system toxicity.

Autonomic Nervous System Diseases↗

PubMed1990

[Cutaneous atypical mycobacteriosis due to Mycobacterium kansasii--a case report and a review of the literature].

A case of cutaneous atypical mycobacteriosis due to Mycobacterium (M.) kansasii is reported. A 41-year-old man, who had lived in Kawasaki city, was seen in April 1988 because of sores on the dorsum of left forefinger which had been present for one month. Physical examination revealed an erythematous, edematous plaque approximately 2 and 4 cm overlying proximal and middle phalanx of left index finger. Otherwise his physical findings were normal. Laboratory studies including X-ray examinations of the chest and left hand were normal. The histopathology revealed a mixed cellular infiltration consists of mononuclear cells and neutrophils with necrosis in the dermis. No granuloma formation was observed. In the deep dermis, some acid fast bacilli (AFB) were demonstrated. The culture for AFB was positive with the following characteristics: Acidfastness (+), Niacin (-), Photochromogenecity (+), Growth at 37 degrees C (+), at 42 degrees C (+), at 45 degrees C (-), Nitrate reduction (+), Catalase (+). These tests were diagnostic of Group I photochromogen, M. kansasii. We reviewed 19 cases of cutaneous atypical mycobacteriosis due to M. kansasii in the world literature including our case and found that there were three types of the disease: (1) Cutaneous chronic granulomatous type, (2) Disseminated acute pyogenic type and (3) Cutaneous pyogenic type.

Adult↗

PubMed1990

[Clinical features of male SLE patients--summary of our 22 cases].

We investigated clinical features of our 22 male SLE patients with main respect to 11 articles of ARA criteria for diagnosis of SLE (1982). As for skin lesions, 14 cases (64%) manifested wide spread discoid lupus erythematosus as their first symptoms, however, rather rare lesions could be seen as follows: 3 cases with nodular cutaneous lupus mucinosis, 1 with vesiculobullous LE. As to visceral manifestations, renal involvements could be seen in 11 cases (50%), among which 6 showed nephrotic syndromes. In immunological examinations, 1 case revealed C4A deficiency. The clinical tendency of male SLE cases has not been settled by now, for the disease is uncommon in men. Each of our 22 cases manifested a variety of features respectively, indicating that rather atypical cases as SLE can be more often seen in males than females. In addition, many of our cases showed remarkable changes clinically during their courses, which suggests that we should follow them carefully from now.

Adolescent↗

PubMed1990

Synthesis and angiotensin converting enzyme inhibitory activity of N-carboxymethyldipeptides with an omega-aminoalkyl group.

A series of novel L-alanyl- and L-lysyl-L-proline derivatives having an omega-amino-1-carboxyalkyl group was prepared, and assayed for their inhibitory activity against angiotensin converting enzyme (ACE). The dicarboxylic acids possesing S,S,S configuration showed potent in vitro ACE inhibitory activity with IC50 values of 0.68-1.4 nmol/l. The length of the carbon chain in the omega-aminoalkyl moiety was varied from 6 to 9 to investigate the optimal structure for long-acting ACE inhibitors. The most prolonged activity in vivo was observed with N-[8-amino-1(s)-carboxyoctyl]-L-alanyl-L-proline upon i.v. and p.o.

Alkylation↗

PubMed1990

[A case of Binswanger disease with numerous diffuse plaques in the neocortex].

A case of Binswanger disease with numerous diffuse plaques in the neocortex was reported. This male patient had a previous history of hypertension and myocardial infarction. From the age of 60, he developed dysarthria, bradykinesia, marche à petit pas and falling down. Neurological examination at his first admission disclosed muscular rigidity and increased jaw and deep tendon reflexes, but dementia was not found. Brain CT showed moderate brain atrophy and EEG consisted of slow wave dysrhythmia. He was diagnosed of Parkinsonism and treatment started without effects. During his second admission for the treatment of myocardial infarction, at the age of 64, delirium developed. Progressive dementia began and finally he was confined to bed. From the age of 69, spontaneous speech became almost lost. Contracture of the extremities, increased deep tendon reflexes and force grasping were noted. Brain CT showed symmetrical low attenuation in the frontal and parietal white matter with moderate dilatation of the lateral ventricles. At the age of 70, he died of general prostration about ten years after the initial symptoms. Neuropathological findings: Macroscopic findings: The brain weighed 1300 g. Atherosclerotic changes of the large arteries at the base of the brain were moderate. Coronal sections of the brain showed moderate enlargement of the lateral ventricles with multiple small lacunes in the basal ganglia. Microscopic findings: Bilateral diffuse demyelination of the white matter with sparing of the U-fibers was noted. Holzer stain revealed fibrillary gliosis in the left parietal and occipital white matter. Marked adventitial fibrosis of the deep white matter arteries and terminal stages of hyalinosis of the perforating arteries were found. Basal ganglia showed status lacunaris. Bilateral pyramidal tracts were atrophic secondly.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1989

Gas chromatographic determination of nicotinamide in meats and meat products as 3-cyanopyridine.

The determination of nicotinamide as 3-cyanopyridine after dehydration by heptafluorobutyric anhydride (HFB) was performed by gas-liquid chromatography (GLC) with flame ionization detection (GLC-FID) and a column of 5% OV-17 on Chromosorb W AW DMCS at 130 degrees C. Determination was possible with 3-100 micrograms of the dehydrated reaction mixture. The procedure for determining nicotinamide in various meats and meat products involves direct analysis by GLC-FID without a clean-up stage; the detection limit is 5 ppm and the recovery ranged from 93.4 to 104.6% (average 98.0%). Various possible interferents in the samples did not interfere in the production or determination of 3-cyanopyridine. The procedure is suitable for routine use. The dehydrated derivative of nicotinamide was confirmed as 3-cyanopyridine by combined gas chromatography-mass spectrometry and infrared spectrometry.

Chromatography, Gas↗

PubMed1989

The effect of ultraviolet B irradiation on delayed-type hypersensitivity, cytotoxic T lymphocyte activity, and skin graft rejection.

The influence of ultraviolet B irradiation on the induction of delayed-type hypersensitivity reactions to alloantigens by epidermal cells (EC), on the generation of cytotoxic T lymphocyte activity to alloantigens, and on skin graft rejection was studied. After the skin was irradiated with UVB in vitro, EC were obtained. The EC were injected subcutaneously, and the DTH reaction was compared with that induced by non-UVB-irradiated EC. A reduction in the DTH reaction was observed (from 62% to 99.1%). CTL activity in these mice was assessed after in vitro stimulation. CTL activity in mice sensitized with UVB-irradiated EC was significantly reduced. Furthermore, mice sensitized with UVB-irradiated EC did not reject a subsequent skin allograft in an accelerated fashion, whereas mice sensitized with non-UVB-irradiated EC did. The mechanism(s) of these reactions and the clinical application of the UVB irradiation prior to grafting are discussed.

Animals↗

PubMed1989

Small angle X-ray scattering study on Lingula unguis shell.

Lingula unguis shell yields a diffuse small angle X-ray scattering which is caused mainly by the scattering from particles of apatite. In this study, the distribution of particles smaller than 500A was analyzed using the small angle X-ray scattering technique. The non-linear Guinier plot indicates that the shell contains various sizes of apatite particles ranging about 20-460A. The small granules with size about 20-160A in diameter are located in the marginal part of the shell and progressively larger granules are observed internally towards the central part. The scattering is anisotropic in the lateral and central part, where the apatite crystals highly ordered. The combined analysis of wide and small angle diffraction indicates that the particles are elongated in the c-axis direction and, furthermore, their long axes are arranged almost parallel to the direction of growth in these parts. This suggests that small and isotropic particles are formed in the early stage of mineralization and larger ellipsoidal shaped particles are formed in the later stage of mineralization.

Animals↗

PubMed1989

Biological activities of IC201 ((3S,8E)-1,3-dihydroxy-8-decen-5-one), a low molecular weight immunomodulator produced by Streptomyces.

IC201 was found in cultured broth of Streptomyces cirratus as an antitumor antibiotic which was effective in retarding growth of the established solid tumor of Ehrlich carcinoma by treatment starting 8 days after tumor inoculation. It retarded growth of the established solid tumor of IMC carcinoma but had no cytotoxicity at 100 micrograms/ml. IC201 treatment kept NK cell activity of tumor-bearing mice at normal level and stimulated cytostatic activity of peritoneal macrophages. It stimulated phagocytosis of yeast and phorbol myristate acetate-elicited superoxide production by peritoneal macrophages. The addition of IC201 to P388D1 cell cultures enhanced release of interleukin 1 (IL-1) into cultured supernatant but it affected lipopolysaccharide-induced IL-1 production. Although the addition to macrophage-depleted cultures did not show any stimulatory effect, mixed lymphocyte culture reaction was augmented in cultures using spleen cells as stimulator cells taken from mice given IC201. Results indicate that IC201 primarily activates macrophages and the activation may cause modulation of immune responses.

Adjuvants, Immunologic↗

PubMed1989

[Selection error of upper anterior artificial teeth].

Seventy two cases of selection error of upper anterior artificial teeth due to the esthetic factors were investigated out of the 1,507 cases of removable dentures, which were made at the Prosthodontics department of Nihon University school of dentistry at Matsudo for 17 years from November, 1971 to November, 1988. The following were the results of the investigation. 1. Frequency of the selection errors amounted to 4.8% of the total selected cases as broken down in 1.6% by Shade and 4.0% by Mould, the rate of selection errors of the Mould being significantly high. 2. By Mould, selection errors in Ovoid type occupied a significantly high rate. 3. Regarding frequency of Mould after re-selection ST and TO occupied a high rate of 45.9%. 4. Mould of re-selection were almost uniformly small, showing a trend of intumescence becoming emphatically.

Denture, Partial, Removable↗

PubMed1989

Synthesis and angiotension converting enzyme inhibitory activity of L-lysyl-N-substituted glycine derivatives.

The synthesis and biological activity of novel L-lysyl-N-substituted glycine derivatives which exhibit in vitro and in vivo angiotensin converting enzyme (ACE) inhibition, are described. Particularly, N-[N alpha-(1-carboxy-3-phenylpropyl)-L-lysyl]-N-(4-phenylcyclohexyl)glycine (11e), N-[N alpha-(1-carboxy-3-cyclopentylpropyl)-N epsilon-carbobenzoxy-L- lysyl]-N-cyclopentyl glycine (9h) and N-[N alpha-[1(S)-carboxy-3-cyclohexylpropyl]-L-lysyl]-N-cyclopentyl glycine (19a) showed a strong inhibitory activity at IC50 as low as 0.65, 0.64 and 0.11 nmol/l, respectively. The most potent activity in vivo was observed with the compound 19a after i.v. administration in the rat.

Angiotensin I↗

PubMed1989

[The functional maturation of Langerhans cells in CTL induction during tissue culture].

In the previous report, we investigated the effects of tissue culture on the APC function of murine epidermal Langerhans cells (LC) in the induction of allo-CTL in vitro, and found that (1) cultured ear LC expressed increased amounts of Ia antigens on their cell surface, and (2) they induced extremely enhanced levels of CTL over those produced by freshly prepared ear LC and also (3) cultured tail LC were proved to be able to induce CTL for the first time. It seemed that tissue culture decreased the functional heterogeneity among the murine ear LC and tail LC in addition to that among Ia+ APC in spleen and in epidermis. In this study, we investigated the culture conditions that increase the APC function of LC. Our data indicate that LC cultured with dermal components exhibited more enhanced APC function than LC cultured in single cell suspension with only epidermal cells. Recent studies indicate that IL-1 and GM-CSF, which keratinocytes release, are essential for freshly prepared LC to mature into highly efficient APC that resemble splenic dendritic cells. We found dermal factors are more important than epidermal ones for LC to mature in tissue culture.

Animals↗

PubMed1989

[Graft-versus-host disease-like syndrome following blood transfusion in a patient with duodenal ulcer].

Graft-versus-host disease (GVDH)-like syndrome occurred in a 45 year-old man with duodenal ulcer who had received a transfusion of 8 units of packed red blood cells. Clinical features included high fever, macropapular rash, hepatic dysfunction, pancytopenia and, finally, fatal septicemia. A skin biopsy obtained from the chest revealed satellite cell necrosis of epidermal cells, mononuclear cell infiltrate of the upper dermis and epidermis, and vacuolar degeneration of basal cells. Autopsy bone marrow was aplastic. The occurrence of GVHD in immunologically normal individuals following blood transfusion is extremely rare.

Bone Marrow↗