A lymphocyte chemotactic peptide released from immunoglobulin G by neutrophil neutral thiol protease.

A thermostable and dialyzable peptide, released from rabbit IgG by rabbit neutrophil neutral thiol protease, exhibited a distinct chemotactic activity for rat lymphocytes; it was assumed to be derived from the Fc fragment (but not from the Fab fragment) by the enzyme. This substance seemed to be effective for adherent cells (B cells) from rat spleen, but not for nonadherent cells (T cells). The chemotactic peptide was purified by gel filtration on Sephadex G-50 and G-15 and then by high-voltage paper electrophoresis. As previously described, the IgG residue after release of dialyzable peptide(s) exhibited chemotactic activity for neutrophils but not for macrophages.     

Histochemical Demonstration of Enzyme Activities in Plastic and Paraffin Embedded Tissue Sections

Histochemical staining for enzymes is usually performed on frozen sections. This report lists the longer incubation times required to demonstrate esterase, acid phosphatase, β-galactosidase, and cytochrome oxidase in plastic embedded and routine paraffin embedded tissues. The sections embedded in plastic, i.e. water soluble methacrylate (Polyscience's JB-4) and cut at 2 μm, were far superior to frozen Sections and paraffin embedded sections both in tissue detail and in the localization of the histochemical reaction product.     

Simplified determination of lorazepam and oxazepam in biological fluids by gas chromatography—mass spectrometry

Lorazepam and oxazepam in plasma and urine were measued by gas chromatography—mass spectrometry. Oxazepam was used as an internal standard in the assay of lorazepam and vice versa. After removal of interfering substances with n-hexane, the drugs were extracted with benzene and converted to N₁,O₃-bistrimethylsilyl derivatives. Glucuronide forms of the drugs were extracted after hydrolysis with β-glucuronidase. A common fragment ion at m/e 429 was used to monitor the two drugs. The sensitivity was 2 ng/ml for both drugs, which was sufficient to determine plasma and urine concentrations after therapeutic doses to humans.     

Synthesis of methyl α- and β-maltotriosides and aryl β-maltotriosides

Reaction of β-maltotriose hendecaacetate with phosphorus pentachloride gave 2′,2″,3,3′,3″,4″,6,6′,6″,-nona-O-acetyl-(2)-O-trichloroacetyl-β-maltotriosyl chloride (2) which was isomerized into the corresponding α anomer (8). Selective ammonolysis of 2 and 8 afforded the 2-hydroxy derivatives 3 and 9, respectively; 3 was isomerized into the α anomer 9. Methanolysis of 2 and 3 in the presence of pyridine and silver nitrate and subsequent deacetylation gave methyl α-maltotrioside. Likewise, methanolysis and O-deacetylation of 9 gave methyl β-maltotrioside which was identical with the compound prepared by the Koenigs—Knorr reaction of 2,2′,2″,3,3′,3″,4″,6,6′,6″-deca-O-acetyl-α-maltotriosyl bromide (12) with methanol followed by O-deacetylation. Several substituted phenyl β-glycosides of maltotriose were also obtained by condensation of phenols with 12 in an alkaline medium. Alkaline degradation of the o-chlorophenyl β-glycoside decaacetate readily gave a high yield of 1,6-anhydro-β-maltotriose.     

Heterogeneous profile in thermal denaturation of DNA preparation from the non-sulfur purple photosynthetic bacterium Rhodopseudomonas spheroides

Thermal denaturation profiles of DNA preparations from fourstrains of Rhodopseudomonas spheroides were comparatively studied.All the melting curves in 0.1 ? SSC displayed Tm at 82 ?0.5?and a faint bimodal transition near 78?. The differential meltingrates as a function of temperature exhibited several peaks,suggesting that inter- or intra-molecular structural heterogeneitymay be present in R. spheroides DNA. ¹ Present address: Biological Institute, Faculty of Science,Tohoku University, Sendai, Japan. (Received February 15, 1975; )     

Incorporation of tritium into cell materials of Rhodopseudomonas spheroides from tritiated water in the medium under aerobic conditions.

When Rhodopseudomonas spheroides cells grown aerobically in the dark were incubated in medium containing tritiated water (THO), incorporation of T into the bacterial cell materials occurred under growth and no-growth conditions. The overall T incorporation under no-growth conditions was stimulated by vigorous aeration and was suppressed strongly in the presence of either 10(-3) M KCN or 0.3% HgCl2, indicating that the bulk of the incorporation might depend upon bacterial cell metabolism or respiration. 10 mug/ml chloramphenicol and 20 mug/ml rifamipicin slightly suppressed the T incorporation. The extent of T incorporation was proportional to the concentration of T in the medium. Accordingly, regardless of differences in the concentration of T in the medium, the maximum ratio of T content per hydrogen atom in the cell materials to that of THO in the medium was approximately 0.2 in non-growing cells and 0.5 in growing cells, whereas the value was 0.02-0.03 in cells incubated in medium containing KCN or HgCl2. The non-growing cells aerated in THO medium were lyophilized and fractionated by the modified method of Schneider. More than 40% of the total T incorporated into the cell materials was recovered in the cold PCA-soluble fraction, whereas the distribution of T into fractions solbule in ether-ethanol, hot PCA and alkali was 10 to 20% each. More than 75% of the T extracted in the cold PCA-soluble fraction was volatile. While the amounts of RNA and protein in the non-growing cells decreased on adding chloramphenicol or rifampicin, the distribution of T in these fractions did not change much. Our results on T incorporation into non-growing cells indicate that the major T incorporation into bacterial cell materials is independent of biosynthetic reactions using labeled precursors produced by the assimilation of T into metabolites, but presumably depends on energy-linked conformational changes of macromolecules.     

Transient characteristics of universal cells on human‐induced pluripotent stem cells and their differentiated cells derived from foetal stem cells with mixed donor sources

IntroductionIt is important to prepare ‘hypoimmunogenic’ or ‘universal’ human pluripotent stem cells (hPSCs) with gene‐editing technology by knocking out or in immune‐related genes, because only a few hypoimmunogenic or universal hPSC lines would be sufficient to store for their off‐the‐shelf use. However, these hypoimmunogenic or universal hPSCs prepared previously were all genetically edited, which makes laborious processes to check and evaluate no abnormal gene editing of hPSCs.MethodsUniversal human‐induced pluripotent stem cells (hiPSCs) were generated without gene editing, which were reprogrammed from foetal stem cells (human amniotic fluid stem cells) with mixing 2‐5 allogenic donors but not with single donor. We evaluated human leucocyte antigen (HLA)‐expressing class Ia and class II of our hiPSCs and their differentiated cells into embryoid bodies, cardiomyocytes and mesenchymal stem cells. We further evaluated immunogenic response of transient universal hiPSCs with allogenic mononuclear cells from survival rate and cytokine production, which were generated by the cells due to immunogenic reactions.ResultsOur universal hiPSCs during passages 10‐25 did not have immunogenic reaction from allogenic mononuclear cells even after differentiation into cardiomyocytes, embryoid bodies and mesenchymal stem cells. Furthermore, the cells including the differentiated cells did not express HLA class Ia and class II. Cardiomyocytes differentiated from transient universal hiPSCs at passage 21‐22 survived and continued beating even after treatment with allogenic mononuclear cells.