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Biomedical subjects

M Yamazaki

Publications and source records attributed to M Yamazaki.

At least 415 records · Page 23Linked to original sources
PubMed1995

Haemostatic and fibrinolytic parameters in septic patients with leukopenia or leukocytosis.

Induction of leukocytopenia by cytotoxic drugs protects against the generalized Shwartzman reaction induced by endotoxin. To elucidate the relationship between leukocyte number and in haemostatic and fibrinolytic disturbances in human sepsis, we studied 32 septic patients with abnormal leukocyte counts. Twenty patients had sepsis in the setting of leukopenia after chemotherapy for haematological malignancies. Twelve patients with leukocytosis developed sepsis associated with benign disorders. Concentrations of thrombin-antithrombin III complex (TAT), plasminogen activator inhibitor-1 (PAI-1) and plasma thrombomodulin (TM) in the leukocytosis group of (12.0 +/- 11.0, 40.2 +/- 27.0 and 5.5 +/- 2.3 ng/ml, respectively) were significantly elevated compared to the leukopenia group of (3.8 +/- 2.3, 18.0 +/- 15.0 and 3.1 +/- 1.0 ng/ml, respectively) and controls (3.3 +/- 0.4, 10.5 +/- 5.3, 3.0 +/- 0.5 ng/ml, respectively). On the other hand, there were no significant differences in these values between leukopenia group and controls. Thus leucocytes may play important roles in thrombin generation, PAI-1 release and injury to endothelial cells.

Adult↗
PubMed1995

The vasodilatory effects of ketamine on isolated rabbit portal veins.

The vasodilation mechanism induced by ketamine was investigated in isolated smooth muscle strips of rabbit portal veins. Ketamine inhibited both the phasic and tonic components of K(+)-induced contraction at concentrations greater than 500 microM and 100 microM, respectively. This effect was reversible and concentration-dependent with concentration-dependent with concentrations up to 1 mM. These effects were similar to those produced by verapamil. In the presence of 60 mM K+, application of Ca2+ (2.5 mM) in the perfusing solution caused tonic contraction of the smooth muscle, and ketamine at concentrations larger than 10 microM strongly inhibited this Ca(2+)-induced contraction. Ketamine (100 microM) also inhibited the K(+)-induced contractions significantly in the absence and presence of guanethidine, tetrodotoxin and propranolol. Ketamine produced similar concentration-dependent relaxations in the tissues with and without endothelium. These results indicate that in rabbit portal vein, vasodilation produced by ketamine is not endothelium-dependent but is likely to be due to blockade of the voltage-gated influx of extracellular Ca2+.

Animals↗
PubMed1995

A case of angiocentric T-cell lymphoma presenting as lethal midline granuloma.

A case of angiocentric T-cell lymphoma with glabellar skin being the only affected site was reported. A 43-year-old woman had a several months' history of glabellar swelling followed by progressive and destructive ulceration of the region. Histopathology of the biopsied specimen showed panniculitis with atypical lymphocytes and degenerative vessels filled with atypical cells. Most of the infiltrated lymphocytes were positive for CD2, CD3, CD4 and CD5. Antibodies to Epstein-Barr virus were detected in the patient serum. Intensive chemotherapy using a protocol of the L17M regimen was partially effective for clinical manifestations. Angiocentric T-cell lymphoma presenting as lethal midline granuloma is a rare but distinct entity with an acute fatal course.

Adult↗
PubMed1995

Pharmacologically active components of Todopon Puok (Fagraea racemosa), a medicinal plant from Borneo.

The lignans of (+)-pinoresinol, (+)-epipinoresinol, (+)-lariciresinol and (+)-isolariciresinol together with phenols such as syringaldehyde and 7,8-dihydro-7-oxy-coniferyl alcohol were isolated from Todopon Puok (Fagraea racemosa Jack ex Wall), a medicinal plant from Borneo, using a bioassay of the relaxation effect on norepinephrine (NE)-induced contraction in rat aortic strips. The plant extract also exhibited analgesic properties in the acetic acid-induced writhing and tail pressure tests in mice, with the activity being concentrated in the lignan fraction. (+)-Pinoresinol showed analgesic effect on writhing symptoms in mice which were dose-dependent, and produced local anesthesia in guinea pigs.

Analgesics↗
PubMed1995

Isolation of some immunosuppressive components from an ascomycete, Gelasinospora multiforis.

Five new components, named multiforisins A, B, C, D, and E, with immunosuppressive activity were isolated from an Ascomycete, Gelasinospora multiforis. Multiforisin A, the main immunosuppressive principle of this fungus, was deduced to be 5-formyl-3-(hydroxymethyl)-4-methoxy-6-(1E-propenyl)-alpha-pyrone. Multiforisins B, C, D, and E were also deduced to be alpha-pyrone derivatives related to multiforisin A. The IC50 values of multiforisins A, B, C, D, E, and dihydro multiforisin A were evaluated against proliferation of mouse spleen lymphocytes stimulated with concanavalin A and lipopolysaccharide.

Ascomycota↗
PubMed1995

[Kinetic analysis of hepatobiliary transport of drugs: importance of carrier-mediated transport].

The liver is the major organ involved in the metabolism and elimination of xenobiotics. Evaluating accurately hepatic clearance is very important for predicting the pharmacological effect and/or side-effects of drugs, as well as changes in drug disposition during disease. Recently, for many endogenous and exogenous compounds (including drugs), it has been reported that carrier-mediated transport contributes to hepatic uptake and/or biliary excretion. In particular, primary active transport mechanisms have been shown to be responsible for the biliary excretion of anticancer drugs, endogenous bile acids and organic anions including glutathione and glucuronic acid conjugates. We have found that a rate-limiting step for several drugs in terms of the hepatic clearance was the membrane transport process. For these drugs, such a saturable transport process can be one of the major determinants which influence not only hepatic clearance itself but also disposition (in other words, plasma elimination) in the whole body. We reviewed the carrier-mediated transport mechanisms involved in the hepatic uptake and biliary excretion processes, the multiplicity of transport systems, and further, the physiological meaning of these complex transport systems in the body.

Animals↗
PubMed1995

[Screening of phagocyte activators in plants; enhancement of TNF production by flavonoids].

The tumor necrosis factor (TNF) was first discovered as a substance that induced necrosis of transplanted tumors. Recently, TNF has been recognized as an important and endogenous mediator in host defense mechanisms. To prove the fact that plant foods contain substances which activate the host defense mechanisms, we first examined if the administration of flavonoids could induce TNF production in mice. Some selected flavonoids such as naringin, apiin, poncirin and rutin were shown to amplify TNF release from murine macrophages in vivo in response to OK-432 as a second stimulus. However, their aglycone forms were not effective. The differences in the saccharide-chain of flavonoids induced the variety of TNF production.

Animals↗
PubMed1995

Involvement of raphe-hippocampal serotonergic and septo-hippocampal cholinergic mechanisms in the penile erection induced by FR121196, a putative cognitive enhancer.

FR121196 (N-[4-acetyl-1-piperazinyl]-4-fluorobenzenesulfonamide), a putative cognitive enhancer, induced penile erection in naive rats; the dose-response curve was bell-shaped with the maximum response obtained at the dose of 3.2 mg/kg. The response to FR121196 was abolished in rats treated with intra-raphe injections of 5,7-dihydroxytryptamine or systemic injections of p-chlorphenylalanine (150 mg/kg, i.p. for three consecutive days) as well as in rats with electrolytic medial-septum lesion or surgical fimbria-fornix lesion. In addition, the penile erection induced by FR121196 (3.2 mg/kg) was dose-dependently attenuated by pindolol (0.1-3.2 mg/kg), a serotonin (5-HT)1 antagonist with beta-antagonistic activity, but not by metoprolol, a selective beta=antagonist. The inhibitory activity was shared by ICS205-930, a 5-HT3 antagonist, but not by ketanserin, a 5-HT2 antagonist, or sulpiride, a dopamine D2 antagonist. Scopolamine (0.032-1 mg/kg), but not methyl-scopolamine (0.032-1 mg/kg), also attenuated the penile erection induced by FR121196. Neurochemical analysis revealed that intraperitoneal injection of FR121196 significantly elevated the levels of 5-HT and its major metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the hippocampus and that raphe-lesion significantly reduced both 5-HT and 5-HIAA levels without affecting choline-acetyltransferase activity in all cortical and subcortical regions examined. It is thus postulated that FR121196 facilitates the raphe-hippocampal serotonergic pathway resulting in an activation of the septo-hippocampal cholinergic pathway and finally induces the penile erectile response.

Animals↗
PubMed1995

Urinary excretion rate of ceruloplasmin in non-insulin-dependent diabetic patients with different stages of nephropathy.

The level of ceruloplasmin, which is a more negatively charged protein than albumin, was measured by an immunoradiometric assay in timed overnight urine and serum samples from patients with non-insulin-dependent diabetes mellitus and healthy controls. None of the plasma proteins examined showed any cross-reactivity in this assay. A linear correlation was seen between the ceruloplasmin level and the serial dilution of the sample. Western blot analysis using concentrated urine samples showed that the molecular weight of ceruloplasmin in the urine sample was the same as that of ceruloplasmin in the serum and standard samples. These findings indicated that the substance detected by this assay was truly ceruloplasmin. The urinary ceruloplasmin excretion rate (CER) and clearance of ceruloplasmin increased in parallel with the progression of albuminuria. The highest CER was found in macroalbuminuric patients, followed by micro- and normoalbuminuric patients and the healthy control subjects, the differences between the groups being significant. In view of the fact that the isoelectric point of ceruloplasmin (4.4) is more acidic than that of albumin, the present findings suggested that an enhanced CER was due either to the alteration of charge selectivity in the glomerular basement membrane with unaltered tubular function or to a defect of the non-discriminatory pores (shunt pathway) with unaltered tubular function.

Adult↗
PubMed1995

A radioimmunometric assay for urinary alpha 2-macroglobulin.

To measure urinary alpha 2-macroglobulin levels, a sensitive radioimmunometric assay was established. The least detectable level of this assay was 225 pg/ml. A linear correlation between alpha 2-macroglobulin levels and serial dilution of urine samples was found. Western blot analysis and study on column chromatography revealed that the molecular weight of alpha 2-macroglobulin in urine was identical to that of serum alpha 2-macroglobulin. The findings suggested that urinary substance detected by the present assay was truly alpha 2-macroglobulin. Timed overnight urine samples from 49 diabetic patients with retinopathy and 20 healthy controls were measured by the present assay. Patients were classified as Albustix-negative and Albustix-positive patients. The highest urinary alpha 2-macroglobulin excretion rates (alpha 2-MER) was found in Albustix-positive patients followed by Albustix-negative patients and the healthy controls. In view of the fact that the stroke radius of alpha 2-macroglobulin (88A) is larger than that of the restrictive pore (56A), the present finding suggests that leakage of alpha 2-macroglobulin in urine may be induced by defect of non-discriminatory pores in the glomerular basement membrane proposed by Deen and colleagues.

Adult↗
PubMed1995

[A case of pure alexia whose writing ability with eyes closed was superior to that with eyes open].

We compared the writing ability between eyes open (looking at one's writing) and eyes closed (without looking) in a case of pure alexia. The patient is a 84-year-old right handed man who developed pure alexia following an infarction in the distribution of the left posterior cerebral artery. He showed right homonymous hemianopsia, slight memory disorder and slight anomia. He could not read any kinds of letters and words at all though he could categorize letters: Kana (phonograms), Kanji (morphograms) and Arabic numbers, and he could distinguish the real letters from false ones. He could achieve almost 60-70% of Kana and Kanji dictation, though it was not perfect. He was often confused and could not continue writing correct letters once interrupted. He wrote poorly when looking at what he was writing. So we compared the ability of dictation with his eyes closed, and that with his eyes open. We found the former way never caused confusion and got better results, which was statistically significant (Fisher's exact test (p < 0.05)). It seemed that his visual feedback of his own writing rather caused trouble in his writing. Thus we concluded that input (reading) process and output (writing) process work simultaneously and bi-directionally. Slight impairment of writing in pure alexia patients might be caused by the effect of impairment of input (reading) process, which is simultaneously connected with the output (writing) process.

Aged↗
PubMed1995

Detection of D1S80 (pMCT118) locus polymorphism using semi-nested polymerase chain reaction in skeletal remains.

We evaluated the usefulness of a semi-nested polymerase chain reaction (PCR) method for detecting D1S80 (pMCT118) locus polymorphisms of DNA extracted from old skeletal remains. The semi-nested PCR has been applied to the amplification of D1S80 nucleic acid sequences. For amplification of the locus D1S80, a pair of oligonucleotide primers have been used widely as described by Kasai et al. We have designed another set of primers for semi-nested PCR. This method resulted in D1S80-VNTR detection from low-titered DNA isolated from old skeletal remains. The first and second step PCR achieved amplification from as little as 10 ng and 10 pg of template DNA, respectively. Specificity and sensitivity of the amplification products was markedly improved by semi-nested PCR. In DNA extracted from biological samples, this method took about 5 hours to amplify the target DNA and 3 hours for electrophoretic separation. We demonstrated that this semi-nested PCR method was superior in sensitivity to conventional 1-step standard amplification for VNTR typing of the D1S80 locus.

Base Sequence↗
PubMed1995

[Comparative study of the efficacy of plasma exchange, immunoadsorption plasmapheresis and corticosteroid administration in the treatment of Guillain-Barré syndrome].

We have retrospectively compared the efficacy of plasma exchange (PE), immunoadsorption plasmapheresis therapy (IAPP), corticosteroid administration and no treatment in the treatment of the Guillain-Barré Syndrome (GBS). Forty-two patients with GBS and clinical functional grades of more than Hughes 3 were admitted to Shinshu University Hospital, Nagano Red-cross Hospital and Saku General Hospital between 1978 and 1994. These patients were treated with either PE, IAPP, corticosteroids or no therapy. Eight were treated with PE, eleven with IAPP, twelve with corticosteroids and eleven were untreated. None of the patients were received combined therapy. The four groups of patients were compared on the following points; duration of the deteliocation in symptoms, duration of the worst symptoms, period of the ability to walk after onset, minimum motor nerve conduction velocity (MCV) over the course, maximum cerebrospinal fluid (CSF) protein concentration over the course, and CSF protein concentration improvement 6 weeks after onset as compared with 2 weeks after onset. The results revealed that the duration of the worst symptoms was shortened more in the IAPP-treated and PE-treated groups than in the other groups. Decreases in CSF protein concentration were more significant in the IAPP-treated and PE-treated groups than in the other groups. There were no significant differences in the other parameters among the groups. Furthermore the clinical symptoms of GBS improved more rapidly with PE and IAPP than with supportive care alone or corticosteroid therapy, especially in the early phase of the disease. IAPP and PE are equally effective.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

[Effects of bupivacaine on Na+ and Ca2+ currents in single canine ventricular cells].

The effects of bupivacaine on Na+ and Ca2+ currents in single canine isolated left ventricular cells were examined using whole-cell voltage clamp technique to reveal the mechanism of its negative inotropism. The cells were isolated by enzymatic dispersion and superfused in an oxygenated Tyrode's solution. Bupivacaine 10(-6) M decreased the amplitude of INa and delayed the peak time. These effects were dose and frequency dependent. At a concentration of 10(-3) M, bupivacaine abolished INa. Meanwhile, bupivacaine did not modify ICa at a concentration of 10(-6) M. At 10(-5) M bupivacaine, the amplitude of ICa was depressed by 22% and the depression was dose dependent. These results suggest that low concentration (10(-6) M) of bupivacaine depresses contraction, by reducing intracellular Ca2+ secondary to reduction in intracellular Na+ activity and the Na+-Ca2+ exchange mechanism. At higher concentrations, the reduction in contraction caused by bupivacaine may result partly from a reduced influx of Ca2+.

Animals↗
PubMed1995

FR121196, a potential antidementia drug, ameliorates the impaired memory of rat in the Morris water maze.

We investigated the effects of FR121196 N-(4-acetyl-1-piperazinyl)-4-fluorobenzenesulfonamide on the performance of rats in the Morris water maze using a two-trial-per-day regimen. Escape latency to find the platform was significantly prolonged in young rats subjected to scopolamine (1 mg/kg) treatment or to nucleus basalis magnocellularis (NBM) or fimbria-fornix (FF) lesioning compared with the respective control animals. Similar memory deficit was observed in aged rats (24-26 months old) compared with young rats. Daily treatment with FR121196 (0.1-1.0 mg/kg i.p.) ameliorated all the memory deficits except in the FF-lesioned rats, whereas physostigmine (0.032-0.32 mg/kg) ameliorated the memory deficits in scopolamine-treated rats but not in the NBM-lesioned, FF-lesioned or aged rats. Methamphetamine (0.32-3.2 mg/kg) hardly ameliorated the memory deficits and, rather, aggravated those in the scopolamine-treated, NBM-lesioned and aged rats. Neurochemical analysis of the brain showed that dopamine, norepinephrine and serotonin levels were significantly reduced in the hippocampus of the FF-lesioned rats compared with the sham control, and a significant reduction of dopamine level in the cortex was also observed in the aged rats compared with young rats. None of these parameters were changed after NBM lesioning. We concluded that FR121196 ameliorates the memory deficits of rats with cholinergic dysfunction through the action on the hippocampal monoaminergic (possibly serotonergic) neurons.

Age Factors↗
PubMed1995

[Allergy histories of Brazilian residents of Japanese descent in Japan].

A questionnaire written in Portuguese was administered from December 1993 to February 1994 to study the frequency of allergic symptoms among Brazilians of Japanese descent in Japan. The results obtained were as follows. 1) The frequencies of allergy histories were 18% for allergic rhinitis, 14% for atopic dermatitis, 12% for alimentary allergy, 10% for allergic conjunctivitis, 9% for allergy to metals, 8% for drug allergy, 7% each for urticaria and pollinosis, and 5% for asthma. 2) The frequencies of allergic rhinitis, allergic conjunctivitis, pollinosis, urticaria and drug allergy were higher among those who came from metropolitan districts in Brazil with severe environmental pollution compared to those who came from rural districts. 3) The characteristics of persons who had subjective symptoms of pollinosis in early spring during their stay in Japan were as follows: The districts they resided in while in Japan were in the Kanto area where the frequencies of Japanese-cedar pollen-specific IgE antibodies positives were high and also where the frequencies of Japanese cedar pollinosis were high among Japanese living in Japan. The districts they originally came from were the metropolitan areas in Brazil, and they were resident in Japan for more than one year.

Adult↗