Molecular cloning of P-type ATPases on intracellular membranes of the marine alga Heterosigma akashiwo

Two cDNA clones (HAA13 and HAA1) which include conserved regions of genes of P-type ATPases were isolated from the marine alga Heterosigma akashiwo by a method that included the polymerase chain reaction. The longer cDNA (3286 bp), HAA13, consisted of an open reading frame that encoded a 106 kDa polypeptide of 977 amino acids with several possible transmembrane domains and conserved regions of eukaryotic P-type ATPases. One transmembrane domain had a leucine zipper structure. HAA1 was not a full-length gene (2054 bp) and lacked the 5' region, but it also included the conserved regions and putative transmembrane domains. Antibodies against the regions and putative transmembrane domains. Antibodies against the polypeptides encoded by HAA13 and HAA1 that have been expressed in Escherichia coli reacted with 100 kDa and 95 kDa polypeptides, respectively, on intracellular membranes of H. akashiwo cells. Immunostaining of H. akashiwo cells revealed that the HAA13 antigen was distributed on membranes around chloroplasts and the HAA1 antigen was located on small vesicles.

Effects of vesnarinone (OPC-8212) on Ca(2+)-activated K channels and cytosolic Ca2+ in cultured smooth muscle cells from porcine coronary artery

Vesnarinone is a new, non vasodilating cardiotonic agent. This study compared the effects of vesnarinone and amrinone, a phosphodiesterase (PDE) inhibitors with vasodilating actions, on cultured smooth muscle cells from the porcine coronary artery. Application of vesnarinone (10(-4) M) or amrinone (10(-4) M) to the bath solution in cell-attached patches activated the KCa channel having a conductance of 133 pS (bath 2.7 mM K, pipette 140 mM K). Application of vesnarinone to the cytosolic side had no direct effect on KCa channel activities in inside-out patches. Activation of the KCa channel was suppressed when the intracellular production of cAMP was suppressed by preincubation with carbachol (10(-6) M). Amrinone, but not vesnarinone, lowered [Ca2+]i in the K(+)-depolarized smooth muscle cells (K+ = 70 mM). These results suggest that vesnarinone exerts an additional effect on [Ca2+]i that is independent of PDE inhibition. The difference in the effects on [Ca2+]i in vascular smooth muscle cells may explain in part the differing actions of these agents on vascular relaxation.

Drug-induced solar urticaria due to repirinast

We describe the first case of drug-induced solar urticaria due to repirinast, an antiallergic drug developed and introduced into the market in Japan in 1987. The patient was a 72-year-old woman who had been on repirinast for 1 year and 8 months. She developed urticaria immediately after an irradiation with 1.5 J/cm2 of UVA, and the provocation test confirmed that repirinast was responsible for the urticarial reaction. The action spectrum of the urticarial reaction was deduced to be 320-350 nm. Passive and reverse passive transfer test results were both negative. However, intradermal injection of patient serum, obtained while she was on repirinast and irradiated in vitro with UVA, demonstrated positive reactions both in the patient and in a normal volunteer. Our findings suggest that nonallergic mechanisms are involved in the reaction. However, the rarity of the phenomenon also suggests an association with some allergic mechanisms.

Identification of causative chemicals of allergic contact dermatitis using a combination of patch testing in patients and chemical analysis. Application to cases from rubber footwear

5 cases of allergic contact dermatitis from rubber footwear were investigated by a combination of patch testing in patients and chemical analysis of causative rubber products. Our studies revealed 2-mercaptobenzothiazole (MBT) and benzothiazyl disulfide (MBTS) (typical allergenic accelerators) as causative chemicals in 3 cases from children's rubber shoes, ladies' rubber boots and ladies' canvas shoes. These 3 patients reacted to mercaptobenzothiazole-type accelerators including MBT and MBTS. MBT and MBTS were determined in each item of causative footwear by chemical analysis, including extraction by shaking with acetone-chloroform (1:1) mixture at room temperature and determination using reversed-phase high-performance liquid chromatography (RP-HPLC). Subsequently, we identified styrenated phenol (SP), a newly found allergenic antioxidant, as a causative chemical in a case from ladies' canvas shoes. The patient reacted to SP but not to MBT and MBTS, though SP, MBT and MBTS were determined in the causative shoes by gas chromatography (GC), GC-mass spectrometry (GC-MS) and HPLC. We also identified p-tert-butylphenol-formaldehyde resin (PTBP-F-R), (a known allergenic adhesive ingredient) as a causative chemical in a case from ladies' sneakers. The patient reacted to PTBP-F-R but not to p-tert-butylphenol (PTBP), MBT and MBTS. These 4 compounds were determined in the causative sneakers by GC, GC-MS and HPLC. Thus, our studies revealed that not only known allergens, such as MBT, MBTS and PTBP-F-R, but also a newly found one, such as SP, were important causes of allergic contact dermatitis from rubber footwear.

Importance of cell aggregation for expression of liver functions and regeneration demonstrated with primary cultured hepatocytes

Adult rat hepatocytes aggregated to form floating multicellular spheroids when cultured in Primaria dishes, which have a positively charged surface, in serum-free Williams' medium E (WE) supplemented with insulin and epidermal growth factor (EGF). These hormones were essential for maintenance of the spheroids, whereas the size of the spheroids depended on the inoculum cell density. The spheroids retained in vivo levels of expressions of albumin and glucokinase and synthesized scarcely any DNA even in the presence of insulin and EGF. On transfer to type I collagen-coated dishes, the spheroids gradually disaggregated and the cells formed monolayers, in which the expressions of albumin and glucokinase were suppressed and DNA synthesis and hexokinase activity were increased. DNA synthesis of hepatocytes in monolayer culture was maximal 24 hr after transfer of the spheroids, approximately 80% of the hepatocyte nuclei were labelled with bromodeoxyuridine during culture for 48 hr, and the mitotic index was approximately 70% after 60 hr. These results suggest that, in spheroids, hepatocytes remained in the G0 phase, but that when they formed monolayers, they progressed to the G1 phase and proceeded through the cell cycle in the presence of insulin and EGF. This work shows that the cell cycle of hepatocytes in culture can be manipulated by providing conditions for quiescence as spheroids or growth as monolayers and that the shape of hepatocytes is important for regulating their growth and liver-specific functions.

Aerobic responses of mouse macrophages to phagocytosis against Escherichia coli as revealed by microphotometry

Fluorescence of peritoneal macrophages, which ingested E. coli labelled with N-[7-(dimethylamino)-4-methyl-coumarinyl]-maleimide, was measured with a microfluorometer. The cellular contents of protein and formazan of a monotetrazolium produced by succinate dehydrogenase (SD) activity were assayed with a microspectrophotometer. During phagocytosis, protein increased in 30 min., but was balanced later by self-hydrolysis. SD activity was unchanged for 30 min. and then increased until 2 hrs. Upon removal of bacteria, the fluorescence and protein decreased with time, whereas SD activity increased further for 1 hr. before decrease. This indicates a delayed activation of the enzyme. The cellular ATP content was reduced during phagocytosis and restored to the normal level 3 hrs. after removal of bacteria. Both KCN-sensitive and -insensitive oxygen uptakes increased in phagocytosis. Thus, oxidative metabolism of macrophages is stimulated in phagocytosis and the stimulation can be demonstrated in situ by the microphotometric methods.

Enhancement by monocytes of perforin production and its gene expression by human CD8+ T cells stimulated with interleukin-2

Pore‐forming protein (PFP) is an important effector molecule for cytotoxicity mediated by cytotoxic T cells and NK cells. In the present study, the effect of monocytes on PFP production by inter‐leukin‐2 (IL‐2)‐stimulated T lymphocytes was examined. Highly purified lymphocytes (>99%) and monocytes (> 90%) were isolated by centrifugal elutriation from peripheral blood of healthy donors, and, CD4+ and CD8+ cells were isolated from the purified lymphocytes by using antibody‐bound magnetic beads. PFP production was quantitated with a universal microspectrophotometer in combination with immunostaining using anti‐PFP antibody. Monocytes did not produce any PFP. High levels of PFP production were observed in CD8+ cells, but not CD4+ cells after incubation for 4 days with IL‐2. Addition of monocytes to cultures of CD8 + cells resulted in significant augmentation of PFP production after 3 days’ stimulation with IL‐2. Monokines (TNFα and IL‐6) caused a significant increase in PFP production by IL‐2‐stimulated CD8+ cells. Northern blot analysis revealed that the PFP mRNA level was enhanced by stimulation with IL‐2, and that addition of monocytes to cultures of CD8 + cells plus IL‐2 augmented their PFP mRNA expression. These observations suggest that monocytes are important in in situ regulation of the CD8 + T cell‐mediated cytotoxic response through production of PFP.

Regulation of gene expression of proteasomes (multi-protease complexes) during growth and differentiation of human hematopoietic cells

We have reported that proteasomes are expressed at abnormally high levels in various hematopoietic tumor cells (Kumatori, A., Tanaka, K., Inamura, N., Sone, S., Ogura, T., Matsumoto, T., Tachikawa, T., Shin, S., and Ichihara, A. (1990) Proc. Natl. Acad. Sci. U.S.A. 87, 7071-7075). In the present study, we examined changes in the expressions of proteasomes during growth of peripheral T-lymphocytes from healthy adults and differentiation of human leukemic cell lines. Up-regulation of mRNAs encoding multiple proteasome subunits was observed during proliferation of resting T-cells induced by mitogens such as phytohemagglutinin and interleukin-2. In contrast, in vitro terminal differentiation into monocytic, granulocytic, and erythroid cells of various immature leukemic cell lines, such as HL-60 promyelocytic leukemia cells and K562 erythroleukemia cells, by various inducing agents caused rapid and marked down-regulation of proteasomes expression, independently of the cell type, direction of differentiation, or type of signal. The syntheses of proteasome subunits of 21-31 kDa and their associated components of 35-110 kDa, measured by [35S]methionine incorporation, were much higher in mitogen-activated T-cells and unstimulated HL-60 cells, which grow rapidly, than in resting and differentiated cells, indicating apparent correlations of the mRNA levels of proteasomes with their translational activities. However, immunochemically, no detectable difference in the cellular contents of proteasomes was found in these cells in induced and uninduced states for proliferation and differentiation, suggesting accelerated turnover of proteasomes in rapidly proliferating cells. Inhibition of proteasome expression by an antisense oligodeoxynucleotide for the largest proteasome subunit, C2, caused partial arrest of cell cycle progression of T-lymphocytes, suggesting that up-regulation of proteasomes is indispensable for proliferation of the cells. We also observed that the nuclear fraction of proteasomes increased in proliferating T-cells and that proteasomes moved rapidly between the nucleus and cytoplasm during differentiation of HL-60 cells.

Scarified photopatch testing in lomefloxacin photosensitivity

We report the results of scarified photopatch testing in 3 patients with photosensitivity to lomefloxacin, a new quinolone antibacterial agent introduced onto the Japanese market in April 1990. The patients developed pruritic eczematous lesions on sun-exposed areas 5 days to 3 weeks after they had started taking lomefloxacin. 2 cases reacted positively to lomefloxacin on scarified photopatch testing down to 0.1% pet., and 1 patient down to 10% pet. One of them also showed positive reactions on conventional photopatch testing. Scarified photopatch testing with 7 other pyridone carbonate derivatives in 2 of the 3 cases, however, did not show any positive reactions. Patch and scarified patch testing were negative in all patients. The clinical course, clinical and histological findings and results of skin tests in these patients suggest that photoallergic mechanisms are involved. This is the 1st report of positive reactions on scarified photopatch testing, which appears to be a useful method of detecting the causative drug in drug-induced photosensitivity.

Effects of time-varying electromagnetic fields on K+ (Rb+) fluxes and surface charge of HeLa cells

The magnetic flux density was varied intermittently from 0.35 to 1.77T and from 0.07 to 1.54 or 1.77T by manual and automatic switchings, respectively, of the power source of an electromagnet. The durations of the "switching-on time" and "-off time" were varied but kept equal. An electric eddy current induced in the culture medium by changes in the magnetic flux density was simulated. When the durations were shorter than 10s, ouabain-sensitive Rb+ influx (active K+ influx) into cultured HeLa cells was significantly inhibited, but the ouabain-insensitive Rb+ influx (passive K+ influx) was not influenced significantly. Inhibition of active Rb+ influx increased with time during exposure for 2 h. Conversely, K+ efflux from the cells was significantly stimulated by the exposure. Microfluorometric examinations of cells loaded with the fluorescent pH indicator 4-heptadecyl-7-hydroxycoumarin (6 microM) and the membrane potential indicator diS-C3-(5) (1 microM) suggested increase in the negative charge on the cell surface during exposure. The observed changes in the K+ (Rb+) fluxes would be related to change in the electric properties of the cell surface caused by exposure to intermittent electromagnetic fields.

Allergic contact dermatitis from para-tertiary-butylphenol-formaldehyde resin (PTBP-FR) in athletic tape and leather adhesive

4 girls with severe allergic contact dermatitis from a brand of athletic tape and a cobbler with allergic contact dermatitis from leather adhesive are presented. Alkylphenol resin with unknown chemical structure had been compounded in both products. One of the girls developed foot dermatitis later from the adhesive used on the inside of new sneakers. By patch testing and chemical analysis of alkylphenol resin and the products, the 5 patients were given a specific diagnosis of allergic contact dermatitis from PTBP-FR.

Allergic contact dermatitis from croconazole hydrochloride

We report 6 cases of contact sensitivity to croconazole hydrochloride, a new imidazole antimycotic drug introduced to the Japanese market in 1986, and available as 1% gel and cream. 6 sensitized patients reacted on patch testing to croconazole hydrochloride down to 0.5 to 0.1% pet, and 3 appeared to be cross-sensitized to sulconazole nitrate. In Japan, allergic contact dermatitis to this drug has now been detected in 12 cases, including our own 6. Prescribers should be aware of contact sensitivity to this drug.

Cytofluorometric determination of nuclear DNA in heart muscles of patients with muscular dystrophy

The degree of DNA-polyploidy of cardiac muscle cells was investigated by cytofluorometry in 4 cases of progressive muscular dystrophy (DMP) and 2 cases of myotonic dystrophy (DM), and the results were compared with those for non-dystrophic hearts of normal or increased weight. The heart muscle cells from all patients with these forms of dystrophy showed marked nuclear DNA hyperploidy reaching 16c, irrespective of cardiac hypertrophy or atrophy. In the non-dystrophic group, DNA hypertrophy corresponding to that of dystrophy was only detected in cases of marked cardiac hypertrophy exceeding a weight of 400 g. The wasting of the respiratory musculature, deformity of the thorax and cardiac muscular atrophy appeared to be the principal factors causing DNA polyploidy in patients with muscular dystrophy.

[Induction of tumoricidal properties in human monocytes by synergism between interferon-gamma and liposome-entrapped muramyl tripeptide]

Human blood monocytes from healthy volunteers, separated by centrifugal elutriation, were not cytotoxic to allogeneic A 375 melanoma cells. The monocytes were rendered tumoricidal by incubation for 24 h with natural interferon-alpha and beta or recombinant interferon-alpha A and alpha A/D (more than 100 U/ml) or with interferon-gamma (more than 1 U/ml). Liposome-MTP-PE at concentrations of more than 50 nmol/ml also induced tumoricidal activity of monocytes. When a combination of subthreshold concentrations of these IFNs and liposome-MTP-PE were added to monocyte cultures, IFN-alpha and beta acted additively in monocyte activation, while IFN-gamma acted synergistically. The synergism for monocyte activation required that monocytes be incubated first with IFN-gamma and then with liposome-MTP-PE. These findings suggest that the synergistic effect of IFN-gamma and liposome-MTP-PE can decrease the necessary clinical doses of these agents for malignant diseases, and may have therapeutic availability in the treatment of metastatic cancer in humans.

Histochemical modification of the active site of succinate dehydrogenase with N-acetylimidazole

The kinetics of acetylation of mitochondrial succinate dehydrogenase [EC 1.3.99.1] in the two fibre types (A and C) of rat gastrocnemius with N-acetylimidazole was studied by a newly modified histochemical technique. Acetylimidazole partially inactivated the enzyme, but subsequent deacetylation with hydroxylamine restored the enzyme activity completely. Inactivation of the enzyme by acetylimidazole was prevented by malonate, which is a competitive inhibitor of the enzyme. The value of the inhibition constant (Ki = 34 microM) for malonate, obtained from the dependence of the pseudo-first order rate constant of acetylation of the enzyme with acetylimidazole on the malonate concentration, was in good agreement with the Ki value (33 microM) obtained by a different method, the dependence of the initial velocity of succinate oxidation by the dehydrogenase on the substrate concentration in the presence of malonate. These findings suggest that a tyrosyl residue is located in the malonate binding site (the active site) of succinate dehydrogenase in the gastrocnemius and plays a role in substrate binding, but is not a catalytic group.

Kinetic behaviour of succinate dehydrogenase of three fibre types in skeletal muscle. I. Effects of temperature and a competitive inhibitor

The kinetic behaviour of succinate dehydrogenase [EC 1.3.99.1] in three fibre types of rat gastrocnemius was examined by a quantitative histochemical method without disruption of the cellular structure. 2-(2-Benzothiazolyl)-3-(4-phthalhydrazidyl)-5-styryl-t etrazolium chloride (BPST) and phenazine methosulphate were used as electron acceptors. On measurement of the absorbance value at 530 nm of BPST formazan, produced by the succinate dehydrogenase reaction in sections, it was found that the staining intensity of succinate dehydrogenase was linearly proportional to both the incubation time and the thickness of the slice therefore, the initial velocity of the staining could be calculated. By Michaelis-Menten (1913) treatment of the dependence of the initial velocity on the substrate concentration in the absence and the presence of a competitive inhibitor, malonate, the Km and Vmax values for succinate and the Ki value for malonate were obtained. The Km and Ki values of the three fibre types were similar. The ration of the Vmax values of type A, B and C fibres was 1.0:2.0:3.3. The temperature dependence of the kinetic parameters was very similar in the three fibre types. These findings confirm that the differences in the staining intensity of the three fibre types reflect differences in the amounts, but not the properties, of succinate dehydrogenase.

Quantitative double-staining methods for tryptophyl and cysteinyl residues and protein in model films

The reliability of three new staining methods developed by the authors were examined with polyacrylamide gel films containing concanavalin A and ovalbumin. The methods were a 2-nitrophenylsulphenyl chloride technique for staining tryptophyl and cysteinyl residues together, a nitrophenylsulphenyl-2-mercaptoethanol method for tryptophyl residues only, and the combination of both these techniques with Coomassie Brilliant Blue for staining total protein. The relative contents of tryptophyl and cysteinyl residues of concanavalin A and ovalbumin in the films, calculated from absorbance values at 370 and 650 nm of double-stained films, were in good agreement with the theoretical values calculated from their amino acid compositions. Thus, these quantitative double-staining methods are reliable and should be useful for histochemical investigations of changes in the amount and composition of tissue proteins.

Mercury exanthem

We experienced 15 patients with generalized rash, mostly appearing a day or two after breaking a clinical thermometer or during dental treatment. Similar skin manifestations were revealed, suggestive at first glance of mercury exanthem, i.e. diffuse symmetrical erythema predominantly on major fluxural areas. An inverted triangular or V-shaped erythema on both upper antero-medial thighs was a common feature. Severe cases had miliary pustules and/or purpura on erythematous skin. Pruritus or burning sensation was relatively mild. Pyrexia or malaise was a complaint of more than half the patients. Most of the patients had a previous history of contact dermatitis to Mercurochrome, and by patch-testing were found to have contact allergy to several mercurials, especially inorganic ones. Until recently, Mercurochrome had been most widely used as a topical disinfectant in Japan. This seems to be a possible cause of the high incidence of contact allergy to mercurials in this country. From our findings we feel that our patients had developed systemic contact dermatitis due to inhalation of mercury vapor.

Combined quantitative cytophotometric method for staining indolyl and sulfhydryl groups and protein

Sulfenylation with 2-nitrophenylsulfenyl chloride (NPS-Cl), which is specific for tryptophyl and cysteinyl residues in protein, was applied to quantitative histochemistry. By measurement of the absorbance values at 370 nm of sections stained with NPS-Cl, Beer-Lambert's law was found to hold for NPS staining. Treatment of NPS-stained sections with 2-mercaptoethanol (ME) (NPS-ME staining) resulted in sulfenylation of tryptophyl residues only. For determination of the amounts of tryptophyl and cysteinyl residues per unit of protein, protein staining with Coomassie Brilliant Blue (CB) was combined with NPS and NPS-ME staining. CB and NPS-CBB staining also followed Beer-Lambert's law. By measuring the absorbance values at 370 and 650 nm of doubly stained sections, the relative contents of tryptophyl and cysteinyl residues in various tissue proteins were calculated. This method will be useful for the investigation of changes in both protein amount and composition.