Calcium ion stimulated endogenous protein kinase catalyzed phosphorylation of basic proteins in myelin subfractions and myelin-like membrane fraction from rat brain

Polypeptide composition and endogenous phosphorylation were investigated in the subfractions of rat brain myelin isolated by either discontinuous or continuous sucrose density gradient centrifugation of myelin. Similarly, a myelin-like membrane fraction (SN4) was also studied. Observations were made that strongly indicated the presence of a calcium-stimulated protein kinase in a highly purified myelin preparation and which exclusively phosphorylated myelin basic proteins of the membrane preparation. Adenosine cyclic 3',5'-phosphate (cAMP) stimulated kinase on the other hand was found to be considerably enriched in the myelin-like membrane fraction. Although this latter enzyme is also capable of phosphorylating the basic proteins, its effect was at least 5 times weaker compared to the calcium-stimulated myelin protein kinase. Within the gradient subfractions there appeared a close relation between the amount of basic proteins and their calcium-stimulated phosphorylation; a similar relationship, however, was not obtained in the case of cAMP-dependent phosphorylation of myelin basic proteins. The former (i.e., Ca2+-stimulated phosphorylation) was found to require a protein factor that functionally resembled calmodulin. The results thus raises an interesting possibility of the presence of calmodulin-like proteins and a calcium-stimulated protein kinase in adult myelin membrane from mammalian brain, both of which have been hitherto unrecognized constituents of myelin membranes.     

Ethanol vapours above lacrimal fluid in the rabbit

Ethanol was administered intravenously to rabbits. The concentration of ethanol, determined by gas chromatographic analysis, in lacrimal fluid was shown to reflect the concentration in plasma. The vapour above lacrimal fluid was analyzed in situ by the use of a small resistivity sensor that measures ethanol vapours. After a dose of approximately 750 mg/kg, the metabolic rates of ethanol determined by gas chromatographic analysis of plasma (226 +/- 13 mg.kg-1.h-1) and by eye ethanol vapour analysis (210 +/- 8 mg.kg-1.h-1) were virtually identical. The data suggest that ethanol eye vapour analysis may be an attractive, noninvasive method for the determination of ethanol in animals.     

Human proteins IEF 58 and 57a are associated with the Golgi apparatus

A mouse monoclonal antibody (mAB 22-II-D8B) raised against lysed transformed human amnion cells (AMA) has been characterized. The mAB decorated the Golgi apparatus in growing and quiescent cultured monolayer cells (fibroblasts and epithelial cells) of various species as determined by double immunofluorescence labeling and colocalization with galactosyltransferase antibodies. It reacted with the acidic human proteins IEF 58 (Mr = 29,000) and 57a, respectively (Mr = 30,000) (HeLa protein catalogue number; [(1982) Clin. Chem. 28, 766]), Golgi staining was also observed in BS-C-1 cells microinjected with mAB 22-II-D8B suggesting that the epitopes recognized by the antibody are most likely located on the cytoplasmic face of the membranes. The precise localization of the antigens to the various cisternae of the Golgi apparatus could not be demonstrated by immunogold cytochemistry on ultrathin cryosections due to either weak reactivity of the antibody or low concentration of the antigens. Immunofluorescence staining with mAB 22-II-D8B of lymphoid human Molt-4 cells and some human tissues failed to reveal any significant staining even though these expressed high levels of both IEF 58 and 57a. These results are taken to imply that the epitopes recognized by mAB 22-II-D8B may be masked in some cell types.     

Die Diffusion des 59Fe-markierten Hämoglobins,ein Artefakt der Glutaraldehyd-Fixierung

Zusammenfassung Ratten wurden 50–80 c ⁵⁹Fe-Citrat in die caudale Vene injiziert. Nach 3–5tägigem Einbau des markierten Eisens in das Hämoglobin wurden Milz-Blöckchen (2 × 2 × 5 mm) 2 Std in GA vorfixiert oder in Hanks-Lösung (= Kontrolle) überführt. Ein Teil der Blöckchen wurde anschließend in OsO₄-Lösung nachfixiert.Die autoradiographischen Ergebnisse zeigen eine Diffusion des Hämoglobins vom unfixierten Zentrum zur Peripherie des Blöckchens.Aktivitätsbestimmungen, die am ganzen Blöckchen, dessen abgetrennten zentralen und peripheren Anteilen, sowie im Überstand vorgenommen wurden, bestätigen diese Diffusion. Während der OsO₄-Nachfixierung erfolgte ein weiterer Verlust des markierten Hämoglobins aus dem zentralen Teil des Blöckchens, nicht aber aus der vorfixierten Peripherie.

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The diffusion of ⁵⁹Fe-labelled hemoglobin, an artefact of the fixation with glutaraldehyde

Summary Injections of 50–80 c ⁵⁹Fe-citrate into the caudale vein of rats were performed. After 3–5 days of ⁵⁹Fe incorporation into the hemoglobin the spleen was taken off, cut in small blocks (2 × 2 × 5 mm) and prefixed for 2 hours in GA or transfered into Hankssolution (= control). Later on some blocks of the spleen were postfixed in OsO₄ solution.A diffusion of the hemoglobin from the unfixed center to the peripheral tissue of the spleen-block is demonstrated by autoradiographic results.After measuring the radioactivity of the total spleen-block of the separated central and peripherical parts as well as their supernatants a diffusion was confirmed. A further loss of the labelled hemoglobin has been observed during the OsO₄ postfixation from the central part of the spleen-block, but not from the prefixed periphery.

     

Comparative effects of trichothecene mycotoxins on bovine platelet function: Acetyl T-2 toxin,a more potent inhibitor than T-2 toxin

The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10^?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.     

Environmental tracking by females

Human females are generally reserved in their sexuality, in keeping with their heavy investment in reproduction. Males tend to be less reserved. Relative to males, however, females demonstrate more variability in sexuality and are more likely to inhibit or express high levels of sexuality. The heightened variability may in part originate with genetic mechanisms that predispose females toward greater variability (the Lyon hypothesis). Menarche, menstrual cycles, menopause, food reactions, responses to living conditions, reactions to cultural factors, and responses to sexual stimuli and potential mates are unique to or are more variable among females than males. There is a correlation between the variation expressed and female reproductive potential—females tend to shift dramatically from sexual inhibition to sexual expression. Females apparently track the quality of the environment and link their sexuality to reproductive opportunities. Successful male reproduction depends less on quality environments and more on the availability of females. In short, females track the environment; males track the females.     

Calcium ion-stimulated phosphorylation of myelin proteins.

Myelin isolated from the central and peripheral nervous system contains a Mg2+-dependent protein kinase that catalyses phosphorylation of myelin-specific proteins. This phosphorylation is markedly stimulated by Ca2+ but not by cyclic AMP. Evidence was obtained that suggested an involvement of calmodulin-like protein in the stimulatory effects of Ca2+ on myelin phosphorylation.     

The acridine dyes: Their purification,physicochemical, and cytochemical properties

Summary The present investigation was designed to allow a critical comparison of the cytochemical behaviour of commercially available acriflavine dye samples and pure acriflavine and proflavine dyes, regarding their application in automated cell analysis. Thin layer chromatography, NMR-spectroscopy and mass-spectrometry were applied for the identification of the dye composition.This study includes (1) a column chromatographic technique for the purification of larger dye quantities, (2) the investigation of the photodecomposition of different dye samples, and (3) the evaluation of the influence of various acriflavine/proflavine dye concentrations (1.6·10^–3–4·10^–6 mol/l) on to the emission spectrum of stained unhydrolyzed and hydrolyzed chicken erythrocytes.The commercially available acriflavine dye samples showed a much higher reduction in fluorescence intensity than the pure dyes, whereby proflavine faded less than acriflavine. Photodecomposition is markably influenced by dye impurities. Fluorescence emission spectra were registered at various acriflavine and proflavine dye concentrations for unhydrolyzed and hydrolyzed chicken erythrocytes in order to investigate the dye-dye interaction and the behaviour of the cellular DNA-dye complex. Proflavine showed a similar spectral behaviour as acriflavine. The dye concentration-dependent spectral behaviour of the DNA-dye complex of these fluorochromes seems to be a very critical factor. A comparison of quantitative fluorescence measurements can only be performed by staining cells with the same dye quality, because automated cytology requires reproducible information of cells in machinesensible terms.This investigation was supported by a grant from the Bundesministerium für Forschung und Technologie (01 VH 065)     

The acridine dyes: Their purification,physicochemical, and cytochemical properties

Summary The present investigation was designed to allow a critical comparison of the dye purity of six commerical acriflavine samples. Thin layer chromatography, absorption-, IR- and NMR-spectroscopy were applied for the identification of dye components and impurities. Ambiguities regarding the purity of the acriflavine samples have been resolved, showing that: (a) The finding permits the conclusion, that all analyzed samples of the fluorochrome acriflavine are characterized by a two-component dye pattern (acriflavine II and proflavine III), and contain fluorescent impurities. (b) The dye component III was the main component of only one dye sample.The effectiveness of these experiments is concerned with making automated microfluorometric measurement of cells stained with pure dye fractions more quantitative and reproduceable.This investigation was supported by a grant from the Bundesministerium für Forschung und Technologie (01 VH 065)     

吐鲁番市胃食管反流病发生相关危险因素分析（附280例报道）

目的：探讨280例胃食管反流病（GERD）的分布特点及危险因素。方法：对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果：不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者（z=-2．939,P=0．003,）;汉族和维族患者占反流性食管炎和Barrett食管比例分别为42．4％、81_3％及56．5％、18．8％,其中汉族患者Barrett食管比例较高（X2=14．358,P=0．000）;肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高（P〈0．001）。结论：GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。