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Biomedical subjects

K Tsuji

Publications and source records attributed to K Tsuji.

At least 685 records · Page 38Linked to original sources

Single-cell origin of human mixed hemopoietic colonies expressing various combinations of cell lineages.

We have established single-cell culture for human mixed hemopoietic colonies using a micromanipulator. Mononuclear cells from human umbilical cord blood were cultured at a concentration of 1 X 10(4) cells per milliliter in methylcellulose medium containing medium conditioned by phytohemagglutinin-stimulated leukocytes and erythropoietin. It was possible to identify the single hemopoietic progenitors in situ in methylcellulose culture on the basis of unique morphology and migratory ability after 36 to 60 hours of incubation. Candidate single hemopoietic progenitors from methylcellulose medium were individually micromanipulated to secondary culture dishes and cultured for an additional ten to 14 days. The colonies derived from the single progenitors were individually picked and stained with May-Grünwald-Giemsa for analyses of the cellular composition. A total of 288 single cells were individually transferred to second dishes. Then 186 single cells produced secondary colonies consisting of cells in one to five different lineages. A total of 39 single cells produced mixed hemopoietic colonies consisting of cells in two, three, four, and five different lineages. There were eight types of colonies revealing two different lineages, ie, neutrophil (n)-erythrocyte (E), macrophage (m)-E, m-megakaryocyte (M), eosinophil (e)-basophil (b), eE, bE, bM, and EM lineages. Three types of colonies consisting of cells in three lineages were also seen, ie, nmM, nbE, and ebE. There were six types of colonies consisting of cells in four lineages, ie, nmbM, nmEM, nebE, mebM, and meEM. One type of colony consisted of cells in five different lineages (nmbEM). These results indicate the single-cell origin of human mixed hemopoietic colonies expressing various combinations of cell lineages. It also provides experimental data in support of stochastic mechanisms of stem cell differentiation.

Azure Stains↗

Marked prolongation in disappearance half-time of plasma cholecystokinin-octapeptide in patients with hepatic cirrhosis.

For exploration on the elimination of cholecystokinin from the circulation, the disappearance half-time of cholecystokinin-octapeptide was estimated with cholecystokinin specific radioimmunoassay in normal subjects and patients with chronic renal failure and with hepatic cirrhosis. With a brief infusion of 30.4 ng/kg of cholecystokinin-octapeptide for 2 min, plasma cholecystokinin level rose from 16.1 +/- 3.6 pg/ml (mean +/- SE) to 216.5 +/- 6.1 pg/ml at 3 min after starting infusion, and decreased rapidly in a single exponential fashion for 10 min in hepatic cirrhosis. The disappearance half-time of cholecystokinin-octapeptide in patients with hepatic cirrhosis was 2.45 +/- 0.07 min, and it was significantly longer than that in normal subjects (1.30 +/- 0.07) or patients with chronic renal failure (1.70 +/- 0.11). These findings suggest that the liver plays a major role in cholecystokinin-octapeptide elimination in humans.

Adult↗

Release of vasoactive intestinal peptide by intraduodenal infusion of HCl or fat and intramuscular injection of neostigmine in man.

A highly sensitive radioimmunoassay system for plasma vasoactive intestinal peptide (VIP) was developed to examine the effect of intraduodenal infusion of HCl or fat on the plasma VIP levels in healthy subjects, and the effect of intramuscular injection of neostigmine in patients with irritable bowel syndrome (IBS). Intraduodenal infusion of 100 ml of 0.1 N HCl or 10 g fat caused a significant rise in plasma VIP level. Neostigmine (12.5 micrograms/kg) produced a significant rise in plasma VIP level, and the plasma VIP response to neostigmine was significantly greater in the IBS group than in the normal group. These results suggest that VIP might play a role in the pathophysiology of IBS.

Adult↗

Evaluation of robot automated chromogenic substrate LAL endotoxin assay method for pharmaceutical products testing.

The robot automated chromogenic substrate LAL assay method was evaluated for endotoxin testing using three lots each of 12 pharmaceutical products. As many as 216 assays, including automated standard curve construction and sample preparation, can be performed in a single day of unattended operation. The method is linear (r greater than .99) in the range of 0 to 0.2 EU/ml. The precision of the method determined by assaying a lot of calcium gluconate for four days was 6%, 10%, and 10% for within an assay block, between assay blocks, and between assay days, respectively. Recovery of endotoxin when spiked into products ranged from 81% to 110% and was within the statistical variation (2 sigma limit) of the method. The endotoxin levels detected in a biological raw material by the chromogenic substrate assay method correlated well with that of the gel-clot LAL assay method. The endotoxin content of the majority of the pharmaceutical products tested was well below the sensitivity of both the chromogenic substrate and the gel clot LAL assay methods.

Automation↗

[Enhancing activity of bacterial preparations on blood flow in tumor tissue, with reference to cancer chemotherapy. Experimental and clinical studies].

The effect of treatment with bacterial preparations on blood flow in normal and malignant tissues was investigated, clinically and experimentally. The time course of the local effect of the preparations was recorded by Laser Doppler Velocimetry (LDV) via a probe on the surface of normal and malignant tissues directly over the injection site. Experimentally, no definite enhancement of blood flow with OK-432, a streptococcal preparation, was observed in nude mice. Clinically, intradermal administration of OK-432 or tuberculin (PPD) resulted in an approximate 11-or 4-fold increase in blood flow, respectively. The injection of OK-432 into malignant tissues, such as dermal cancer and breast cancer with direct extension to the skin, resulted in an approximate 3.5-fold increase. The results suggested that bacterial preparations can act as an adjuvant to enhance drug delivery to tumor tissue in cancer chemotherapy, and that the enhancement of blood supply is induced by immune response.

Adult↗

Peptidyl carbamate esters: a new class of specific elastase inhibitors.

A series of tripeptide carbamate esters were synthesized and tested for inhibitory activity towards porcine pancreatic elastase, trypsin and chymotrypsin. Two of these compounds specifically inhibited elastase [Ki = 4.25 x 10(-5)M and 3.00 x 10(-5)M], and exhibited no effect toward the other two serine proteases. These active tripeptidyl carbamates represent a novel class of specific elastase inhibitors.

Animals↗

High-performance liquid chromatographic analysis of neomycin in petrolatum-based ointments and in veterinary formulations.

A high-performance liquid chromatographic (HPLC) method has been developed for the assay of neomycin in petrolatum-based ophthalmic and topical ointments and in veterinary formulations. Neomycin assay interferences from drugs, such as bacitracin and polymyxin B and inactive components, e.g. wax, were eliminated by a methanol wash and/or a partitioning method. The extracted neomycin was derivatized with 2,4-dinitrofluorobenzene followed by normal-phase HPLC with detection at 254 nm. The average recovery of neomycin from spiked samples was approximately 100% with a relative standard deviation of less than 1%.

Bacitracin↗

Determination of trace levels of fatty acid metal salts by high-performance liquid chromatography with fluorescence prelabeling.

A simple method is described for picomole determinations of fatty acid metal salts. Fatty acid salts are directly labeled with 4-bromomethyl-7-methoxycoumarin in the presence of excess ethylenediaminetetraacetic acid tripotassium salt without any solvent extractions. The fluorescence derivatives of fatty acids are separated by reverse-phase high-performance liquid chromatography followed by fluorometric detection. The response of each fatty acid (C8-C18) calcium salt is linear from 1 to 50 micrograms/ml of samples. The detection limit is about 7 pmol. Good recoveries are obtained for the calcium salts of myrystic acid and soap (C8-C18, C18:1,2). The new method is successfully applied to the study on biodegradation of fatty acids in river water.

Biodegradation, Environmental↗

Reconstruction of photosynthetic, cyclic electron transport system from photoreaction unit, ubiquinone-10 protein, cytochrome c2 and polar lipids purified from Rhodospirillum rubrum.

It was previously reported that in chromatophores of Rhodospirillum rubrum, reaction center, which consists of three kinds of protein (Mm, about 78K), is a small fragment of a large protein complex (PRU; photoreaction unit), which contains six other kinds of protein including light-harvesting bacteriochlorophyll protein, has Mm of about 700K and is free of phospholipid [J. Biochem. 86, 1211-1224 (1979); 94, 1815-1826 (1983(]. In the present study, the photosynthetic, cyclic electron transport system sensitive to antimycin A was effectively reconstructed by incubating 60 nM PRU (which contained 1 mol of reaction center and 2 mol of ubiquinone-10 per mol) with 300 nM each of oxidized ubiquinone-10 protein, reduced cytochrome c2 and lipoamino acid (which were all purified from Rhodospirillum rubrum) in the presence of low concentrations of cholate and deoxycholate (pH 8.0). In the light, the cytochrome was oxidized while the quinone was reduced. The oxidation and reduction each progressed rapidly at first, then slowly, reaching maxima (steady states) 1-2 min after the light had been turned on. At the steady states, 30% of the cytochrome was oxidized while 11% of the total quinone was reduced. When the light was turned off, the original oxidation-reduction states of the cytochrome and quinone were restored at rapid rates initially then at slow rates. Antimycin A stimulated the slow rates in the light-on state and depressed them in the light-off state, but did not influence the fast rates. Ubiquinone-10 protein was required for the antibiotic-sensitive, slow oxidation reactions. This indicates that the slow rates were due to cyclic electron transport. Cytochrome c2 was tightly bound to PRU at a molar ratio of 1:1. This cytochrome as well as the quinone bound to PRU was responsible for the fast rates. PRU had other sites able to bind cytochrome c2 and ubiquinone-10 protein with Km of 0.4 and 0.1 microM, respectively. Of the polar lipids tested, lipoamino acid was the most effective for reconstruction, and its effect was maximal at 300 nM, which is far below its critical micelle concentration.

Bacterial Proteins↗

Migration of acetylated hemicellulose from capillary hemodialyzer to blood, causing scleritis and/or iritis.

From November 1981 to early March 1982, an outbreak of scleritis and/or iritis occurred among patients treated with a Nipro brand NAC series cellulose acetate capillary dialyzer. The rate of incidence with dialyzers produced in 1982 was significantly higher than that with dialyzers produced in 1981. An extract obtained from the dialyzers caused iritis in rabbits after its infusion into an auricula vein. Glycerol, acetylated carbohydrate (AC) derivatives, urethane derivatives, and polypropyleneglycol were found in the extract. AC derivatives caused iritis in rabbits, whereas they caused hyperemia of the bulbar conjunctiva in dogs. The AC derivatives contained xylose and glucose units in a ratio of 1.6-2.3:1. The amounts of AC derivatives were significantly larger in the extracts from 1982 than from 1981 devices. Moreover, another brand, but the same type, of dialyzer, the Cordis Dow 4000, contained a slight amount of them. These facts show that AC derivatives derived from hemicellulose played a primary role in the outbreak.

Acetylation↗

Automation of chromogenic substrate Limulus amebocyte lysate assay method for endotoxin by robotic system.

The chromogenic substrate Limulus amebocyte lysate (LAL) assay method for the detection of endotoxin was automated by a Zymate robotic system. The software developed enables the robot to automatically dilute a stock reference endotoxin standard (20,000 endotoxin units per ml) for the construction of a five-point standard curve, make sample dilutions to the proper testing concentration, and perform chromogenic substrate LAL assays in duplicate. The linearity of the standard curve and the endotoxin concentration in each sample are calculated and results are printed automatically. In 48 min the automated system assays three samples and a reference standard in duplicate along with a water blank. Sensitivity of the assay is a function of incubation time. The assay is linear (r greater than 0.99) in the region of 0 to 1.0 endotoxin units per ml or 0 to 0.2 endotoxin units per ml with incubation times of 10 or 16 min, respectively. The method can be made very sensitive, detecting as low as 0.003 endotoxin units per ml with 30 min of incubation. The precision of the assay method, determined by assaying an endotoxin reference solution eight times, is ca. 6%. The LAL reagent designed for gel-clot assay was modified for the chromogenic substrate assay. We describe the optimum conditions for the performance of the chromogenic substrate LAL assay and stability of the LAL reagent.

Automation↗

IgA nephropathy associated with HLA-DR4 antigen.

This report describes 2 siblings with IgA nephropathy. Patient No. 1 was a 38-year-old woman with hematuria and proteinuria of 19 years duration. Her blood ABO type was A and Rh positive. She was found to have HLA-A2,Aw24; Bw54 , Bw48 ;Cwl,C-;DR1,DR4. Her renal specimen was diagnosed as the advanced stage of IgA nephropathy histologically. Patient No. 2 was a 41-year-old man who was a brother of patient No. 1. His blood ABO type was O and Rh positive. His serotype for the HLA was found to be HLA-Aw24,A-;Bw35, Bw54 ;Cw1,Cw3;DR4, DRw9 . His renal histology showed the advanced stage of IgA nephropathy. It is suggested that an abnormal immune response linked to gene coding for HLA-DR4 antigen might be involved in the development of IgA nephropathy.

Adult↗

Strong association of idiopathic membranous nephropathy with HLA-DR2 and MT1 in Japanese.

HLA-A, B, DR, and MT antigens were examined in 50 patients with idiopathic membranous nephropathy (IMN) by the standard microlymphocytotoxicity technique. The frequency of HLA-DR2 was significantly increased in the patients in comparison to the controls. Significant decreases in the frequencies were seen for HLA-DR4, DRw8 and DRw9 in the patients. The linkage disequilibrium between HLA-Bw52 and DR2 was noted in the controls, but it was significantly weaker in the patients. The frequency of MT1 was significantly higher, and that of MT3 was significantly lower in the patients as compared with the controls. The findings suggest that an immunological disturbance under the influence of genetic factors may confer a susceptibility to IMN.

Adult↗