Search PubMed⌕ Search

Biomedical subjects

J Matsuda

Publications and source records attributed to J Matsuda.

At least 181 records · Page 10Linked to original sources
PubMed1992

[Clinical studies on panipenem/betamipron in pediatrics].

Panipenem/betamipron (PAPM/BP) was given by 30 minutes drip infusion to 15 children with acute bacterial infections including 11 with acute pneumonia, 2 each with staphylococcal scalded skin syndrome and urinary tract infections. Good to excellent clinical responses were obtained in all of the 15 patients and bacterial eradications were obtained for all 12 strains identified in these cases. Urticaria considered to be drug related was observed in 1 patient. Slight elevations of GOT and GPT and eosinophilia were observed in 1 case each. From the above clinical results, it appears that PAPM/BP is a useful antibiotic for treatment of pediatric patients with various bacterial infections.

Acute Disease↗
PubMed1992

[Chronic fatigue syndrome].

Chronic fatigue syndrome (CFS), which is characterized by devastating fatigue, mild fever, lymphadenopathy, headache, myalgia, insomnia and neuropsychiatric disorders, now has drawn much attentions from many physicians, researchers and even peoples in general society world wide. The pathogenesis of CFS is still remains to be clarified and clinico-pathological difference between CFS and mood disorder is controversial. In this paper, CFS would be reviewed in detail.

Adjuvants, Immunologic↗
PubMed1991

Molecular cloning of hyoscyamine 6 beta-hydroxylase, a 2-oxoglutarate-dependent dioxygenase, from cultured roots of Hyoscyamus niger.

Roots of several solanaceous plants produce anticholinergic alkaloids, hyoscyamine and scopolamine. Hyoscyamine 6 beta-hydroxylase, a 2-oxoglutarate-dependent dioxygenase (EC 1.14.11.11), catalyzes hydroxylation of hyoscyamine in the biosynthetic pathway leading to scopolamine. We report here on the isolation of cDNA clones encoding the hydroxylase from a cDNA library made from mRNA of the cultured roots of Hyoscyamus niger. The library was screened with three synthetic oligonucleotides that encode amino acid sequences of internal peptide fragments of the purified hydroxylase. Nucleotide sequence analysis of the cloned cDNA revealed an open reading frame that encodes 344 amino acids (Mr = 38,999). All 12 internal peptide fragments determined in the purified enzyme were found in the amino acid sequence deduced from the cDNA. With computer-aided comparison to other proteins we found that the hydroxylase is homologous to two synthases involved in the biosynthesis of beta-lactam antibiotics in some microorganisms and the gene products of tomato pTOM13 cDNA and maize A2 locus which had been proposed to catalyze oxidative reactions in the biosynthesis of ethylene and anthocyan, respectively. RNA blotting hybridization showed that mRNA of the hydroxylase is abundant in cultured roots and present in plant roots, but absent in leaves, stems, and cultured cells of H. niger.

Amino Acid Sequence↗
PubMed1991

[Novel PCR methods for detection of HIV proviruses using digoxigenin labelled probes--Southern blot and dot blot].

Polymerase chain reaction (PCR) is useful for diagnosis of HIV infection in the silent stage, for HIV transmission from mother to child and for existence of HIV in blood and blood products. We developed a simple, rapid and safe PCR method by using digoxigenin labelled probes. Furthermore, we developed a semi-quantitative dot blot method. These methods will be helpful for diagnosis.

Blotting, Southern↗
PubMed1991

[Study on serum neopterin concentration in hemophiliacs with anti-human immunodeficiency-virus type I antibody].

The present study was undertaken to discuss whether measurement of neopterin (NP) released into blood from monocytes/macrophage following activation of lymphocytes were useful tool to predict development of AIDS after HIV-1 infection. The subjects used for this study were eighty one cases of hemophilia, of whom 47 cases were HIV-1 antibody tested positive. Serum NP concentration (15.0 +/- 13.8 nmol/l) in anti-HIV-1 antibody-positive group was higher than in-negative group (5.7 +/- 3.3 nmol/l) (p less than 0.05), in which there was no case whose serum NP level amounted to more than 20 nmol/l. In anti-HIV-1 antibody-positive group, in which CD4/CD8 lymphocyte ratio was less than 0.4, serum NP level was significantly higher than in the group whose lymphocyte ratio was more than 0.5 (p less than 0.05). This result represents that there is a reverse correlation of NP concentration with the developing level of immunodeficiency. Furthermore, in eight cases who developed AIDS, serum NP levels turned to increase from several months or earlier until in all cases the levels were more than 30 nmol/l. In three cases of five who were dead, serum NP concentration had decreased to death since several months through one year. These findings reveal that measurement of serum NP concentration is correlated with clinical outcome after HIV-1 infection and it is useful as the marker for prediction of AIDS development. Also these findings represent that a parallel application of serum NP assay to CD4 lymphocyte counting, detection of anti-HIV-1 antibody, IgA, beta 2-microglobulin assays can predict the outcome of the HIV-1 infection more precisely.

Acquired Immunodeficiency Syndrome↗
PubMed1990

An electron microscopic study of glomerular lesions in hereditary nephrotic mice (ICGN strain).

Glomerular lesions in hereditary nephrotic mice (ICGN strain) were investigated by electron microscopy. The glomeruli of unaffected animals, which appeared normal by light microscopy, had developed an ultrastructural change in the glomerular capillary basement membrane (GCBM). There was a partial thickening of the GCBM with bilaminar splitting of the lamina densa and an electron-dense fibrillar material exhibiting cross-striations. In affected animals, light microscopy revealed a marked thickening of GCBM and an increase of mesangial matrix without cellular proliferation. By electron microscopy, multilaminar splitting of the lamina densa in the thickened GCBMs and fusion of the epithelial foot processes were observed. In some severely affected animals, immune complex deposition was found in GCBM, but little if any was observed in other animals. In the end, the glomeruli were globally sclerosed. Our findings suggest that initial structural abnormalities in GCBM may play an important role in the onset and development of the disease, though subsequent events such as immune complex deposition would modify the disease.

Animals↗
PubMed1990

N-nitrosamines in gastric juice of patients with gastric ulcer before and during treatment with histamine H2-receptor antagonists.

The clinical implications of N-nitrosamines (NAs) were studied by analyzing their concentration in the gastric juice of 72 healthy subjects and 279 patients with gastric ulcer before and during treatment with histamine H2-receptor antagonists. NAs were measured by combined gas chromatography and thermal energy analyzer. The detection ratios of N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) in the patients were 35.3% and 34.6%, respectively, which were significantly higher than the corresponding values in healthy subjects (19.4% and 16.7%, P less than 0.01). Analysis among the patients showed that this trend was mainly due to higher values in patients who were given histamine H2-receptor antagonists, as their detection ratios increased to 40.2% (NDMA) and 39.9% (NDEA). Patients without histamine H2-receptor antagonists showed moderate increases of detection ratios (NDMA; 24.2% NDEA; 22.6%) compared with healthy controls. The differences in these values between those receiving and not receiving histamine H2-receptor antagonists were statistically significant (P less than 0.01). The maximum concentrations of NDMA and NDEA were 7.9 and 9.8 ng/ml in patients, and 1.2 and 1.3 ng/ml in healthy subjects (the difference between the 2 groups P less than 0.02). These results indicated that patients with gastric ulcer had higher detection ratios and concentrations of NDMA and NDEA in gastric juice and that, while significant increases occurred during treatment with histamine H2-receptor antagonists, the extent of increase was below toxic or experimental carcinogenic levels.

Adult↗
PubMed1990

N-nitrosamines in the stomach with special reference to in vitro formation, and kinetics after intragastric or intravenous administration in rats.

To study the implications of nitrosation in the stomach, the formation of N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA) from nitrite and secondary amines was examined in vitro under conditions simulating gastric juice. Kinetics of NDMA were investigated after intragastric or intravenous administration of 0.2 mg/kg of NDMA in rats. NDMA and NDEA were measured using combined gas chromatography and thermal energy analyzer. Nitrite levels in human gastric juice were less than 10 micrograms/ml. Optimal pH for nitrosation was between 2.0 to 3.5. Nitrosamine formation reached maximum concentration at 3 to 6 hours. The maximum ratios of nitrosation were 0.15 and 0.11% in NDMA/nitrite and NDEA/nitrite, respectively. In the kinetic study, the highest blood levels of NDMA were observed at 5 min, reaching 174 +/- 40 and 374 +/- 40 ng/ml after administration into the stomach and duodenum, respectively. Then they decreased exponentially and were not detectable after 4 hours. Tissue levels of NDMA in the liver, spleen, kidney, lung and brain showed 70% of the blood levels. Urinary excretion of intravenously administered NDMA during the first 4 hours was less than 0.2%. These results supported the hypothesis that nitrosation occurred in gastric juice under optimal conditions, and indicated that nitrite levels were the limiting factor for nitrosation. Quick disappearance from the gastrointestinal tract suggested that the pathologic implication of nitrosamines formed in the stomach could be important for other organs.

Animals↗
PubMed1990

Efficacy of recombinant human granulocyte colony-stimulating factor on neutropenia in patients with AIDS.

The efficacy of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on neutropenia was evaluated in 14 patients with AIDS and AIDS-related complex (ARC). In all patients, including 11 neutropenic patients, 100 or 200 micrograms/m2 of rhG-CSF significantly increased the neutrophil counts. The response was greater in patients with higher neutrophil counts before the treatment, and was also dose-dependent. Although the effect seemed to be less potent, the agent also increased the neutrophil counts even when zidovudine (azidothymidine, AZT) and other myelosuppressive antiviral agents were administered simultaneously. These observations indicate that rhG-CSF may be beneficial in preventing and treating some secondary infections, and will make it easier to continue therapy with antiviral agents in patients with AIDS or ARC.

AIDS-Related Complex↗
PubMed1990

Basolateral K+ channels in airway epithelia. I. Regulation by Ca2+ and block by charybdotoxin.

In airway epithelia, adenosine 3',5'-cyclic monophosphate (cAMP) stimulates Cl- secretion by activating apical membrane Cl- channels and basolateral membrane K+ channels. Cl- channels are regulated by cAMP-dependent phosphorylation, whereas K+ channels are regulated by the cytosolic Ca2+ concentration, [Ca2+]c. Our recent observation that cAMP increases [Ca2+]c suggested that cAMP might indirectly regulate K+ channels by increasing [Ca2+]c. To study regulation of K+ channels we measured 86Rb efflux, single K+ channels in membrane patches, and [Ca2+]c with the fluorescent indicator fura-2. Isoproterenol and Ca2+ ionophore, A23187, transiently increased [Ca2+]c and transiently stimulated 86Rb efflux. Stimulation of 86Rb efflux resulted from release of intracellular Ca2+ stores. 86Rb efflux was blocked by Ba2+ or charybdotoxin, but not by tetraethylammonium. Charybdotoxin prevented all of the 86Rb efflux that was stimulated by A23187 or by forskolin. Charybdotoxin also blocked the low-conductance inwardly rectifying K+ channel (KCLIC) in membrane patches. These results indicate that the KCLIC channel is responsible for the Ca2(+)-dependent increase in K+ permeability in airway epithelial cells. They also indicate that cAMP-induced release of intracellular Ca2+ is sufficient to activate K+ channels.

Animals↗
PubMed1990

Participation of ovarian 20 alpha-hydroxysteroid dehydrogenase in luteotrophic and luteolytic processes during rat pseudopregnancy.

In normal rats, before Day 12 of pseudopregnancy, minimal levels of 20 alpha-HSD activity were detected in functional CL whereas those in the residue were 3-5 times higher. When ovulation was blocked for more than 2 weeks by placing rats in a continuously lit environment before the induction of pseudopregnancy, only minimal levels of 20 alpha-HSD activity were detectable in the functional CL and residue before Day 12. In normal pseudopregnant rats, there was a linear increase in 20 alpha-HSD activity from Day 12 to 15 in the functional CL and residue, but the rate of elevation was much higher in functional CL. This tendency was much more clear-cut in rats in the continuous lighting. In immature rats in which pseudopregnancy was induced by PMSG and hCG treatment, 20 alpha-HSD activity peaked twice. The first small peak was attributed to the early regression of some of the large number of corpora lutea, and the changes in 20 alpha-HSD activity in most of the corpora lutea paralleled those in rats in continuous lighting. Bromocriptine abolished the prolactin surges, and in normal pseudopregnant rats an increase in 20 alpha-HSD activity in functional CL started from 12 h and the rate of the increase was accelerated from 36 h afterwards, while a relatively small increase was observed in the residue at 18 h and later.(ABSTRACT TRUNCATED AT 250 WORDS)

20-alpha-Dihydroprogesterone↗
PubMed1990

[Diagnosis of HIV by clinical pathological methods].

HIV (human immunodeficiency virus)-I infection can be detected by the presence of HIV antigen, antibody to HIV, or gene of HIV itself in patient's blood. There are a considerable number of such antibody detecting methods (first generation) commercially available, but even the first was introduced in only mid-1985. These tests detect antibody in more than 90% of patients with confirmed AIDS. Recently, new antibody detecting methods (second generation) was produced using a single antigen (e.g. p 24, gp 41) of HIV-I by recombinant DNA or synthetic peptide. Furthermore, detection methods for DNA or RNA of HIV were developed and these methods are introduced in clinical use in near future.

AIDS Serodiagnosis↗
PubMed1990

[Treatment of paroxysmal nocturnal hemoglobinuria with danazol].

Glucocorticoid and androgen therapy have been used with moderate success in paroxysmal nocturnal hemoglobinuria (PNH). However, both are poorly tolerated, especially in women, although the side effects of glucocorticoid can be diminished by alternate day therapy. We have treated two patients with PNH with danazol. One of patient is man, 64 years old age with stomach cancer, and the other patient is 34-year-old man. Their disease has existed for 6-14 years. They required many blood transfusions, their hemoglobins ranging between 7.1 and 9.9 grams per deciliter. When treated with danazol by mouth, the hemoglobin level increased approximately 2 to 5 grams in each patient within 3 week, and clinical hemoglobinuria improved. None of the patients has had any side effects.

Adult↗
PubMed1989

Prediction of the effect of immunoglobulin therapy in ITP.

The correlation between the response to high-dose immunoglobulin therapy (IVIg) and the sequestration pattern of Indium-labeled platelets (In-PLT) in the body was studied in 9 patients with chronic idiopathic thrombocytopenic purpura (ITP). Patients that has prominent platelet sequestration in the spleen responded to IVIg. In these patients, splenic sequestration decreased by 20-30% after IVIg without significant changes in hepatic sequestration. This finding suggests that the blocking of splenic Fc receptors with immunoglobulin minimized the destruction of sensitized platelets. However, patients who had almost equal platelet sequestration in the liver and spleen did not respond to IVIg. In these patients, hepatic sequestration decreased after IVIg, whereas splenic sequestration increased. Thus, it appears that estimating the platelet sequestration pattern using In-PLT is useful for predicting the effects of IVIg.

Autoimmune Diseases↗
PubMed1989

Effects of tissue geometry on initiation of a cardiac action potential.

We used rabbit ventricular papillary muscles and isolated rabbit ventricular muscle cells to compare the effects of a decrease in cardiac excitability. For the papillary muscles, we defined tissue excitability as the inverse of the current required to initiate a propagated action potential from a local stimulus. For the isolated cells, we defined cellular excitability as the inverse of the current required to initiate a membrane action potential. For papillary muscles, lidocaine with elevated extracellular K+ concentration ([K+]o) decreased maximum rate of rise of membrane potential (Vmax), decreased conduction velocity, and strongly decreased tissue excitability. For the isolated cells, lidocaine with elevated [K+]o decreased Vmax but had little effect on cellular excitability. We interpret our results on the differences of effect on tissue excitability vs. cellular excitability as a consequence of the syncytial nature of the papillary muscle. The cell-to-cell electrical connections produce an electrical load on the locally stimulated region. This electrical load makes the tissue excitability dependent on the amount of inward current that the locally excited cells and the surrounding cells can generate. We simulated these phenomena with numerical solutions of action potential initiation in an isopotential cell compared with a two-dimensional disk of excitable tissue. The simulation results recreate the basic experimental observation that the sensitivity of the current threshold to agents that lower inward current is markedly larger for multidimensional current flow from a source compared with an isopotential system.

Action Potentials↗