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Wounding of quiescent white potato tuber tissue enhances chromatin-boundprotein phosphokinase activity, which exhibits two distinctphases during wound-healing. A moderate activation of the enzymesup to 20 hr after injury is followed by a dramatic increasein activity with a peak at 50 hr. This time-course resemblesthat of chromatinbound DNA-dependent RNA polymerase with a peakin activity at about 48 hr after wounding. The kinases phosphorylateendogenous proteins as well as added histones, phosvitin andcasein. The incorporated phosphate is stable under standardassay conditions, indicating the absence of protein phosphatases.Sensitivity of the incorporated phosphate toward trypsin andalkali, but not DNase, RNase, hydroxylamine or succinic acidpoints to seryl- and threonyl-bonds and proteins as acceptormolecules. Kinases from resting tissues are only weakly stimulatedeven by 100 mM MgCl2, those from wounded tissues exhibit pronouncedMg$$-optima at 5–10 mM with endogenous proteins, phosvitinand casein and 50 mM MgCl2 with histones. Wounding also increasesthe sensitivity of the kinases toward p-hydroxymercuribenzoate. Chromatin preparations from both resting and wounded tissuescontain about 40 protein bands after polyacrylamide disc gelelectrophoresis. In vitro phosphorylation of these proteinsin chromatin from quiescent tissues is comparably low and uniform.Wounding induces changes in the protein and phosphorylationpattern with a general enhancement of phosphorylative capacityand preferential phosphorylation of low molecular weight proteins. (Received August 10, 1981; Accepted November 18, 1981)  相似文献   
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Zusammenfassung 1. Das Bewegungsverhalten der Coelomzellen des EchinoidenPsammechinus miliaris Gmel. wird an kleinen von Stacheln, Füßchen und Pedicellarien befreiten Stellen der Skelettoberfläche in Periproctnähe untersucht.2. Aus dem freiliegenden Bälkchenwerk treten Coelomzellen aus, von denen nur die rotbraunen Amoebocyten auf dem hellen Kalkuntergrund im Auflicht (Ultropak;E. Leitz) sichtbar sind.3. Nach einigen Stunden ist die Wundfläche mit einer dicken rötlichen Zellmasse bedeckt, dem primären Wundverschluß. Außer den Coelomzellen enthält der Wundverschluß noch verschieden große Kalkpartikel, die vom Abschleifen der Versuchsstelle herrühren.4. Bei direkter Beobachtung ist weder an den rotbraunen Amoebocyten noch am Wundverschluß die geringste Bewegung zu erkennen.5. Zeittransformation (Zeitraffung [Z.R.] auf 1/240 und 1/480) zeigt die mit erheblicher Ortsverlagerung und Metabolie verbundene Bewegung der allein wahrehmbaren rotbraunen Amoebocyten auf der Wundfläche. Im scheinbar in Ruhe befindlichen Wundverschluß findet eine ständig hin- und herwogende Bewegung der Zell-Kalkamsse statt.6. Bereits nach 6 bis 7 Stunden ist das Operationsfeld völlig geglättet; die Lücken im Kalkskelett sind kaum noch zu erkennen infolge der neu eingebauten Kalkelemente. Die eigentlichen Heilungsvorgänge (Wiederherstellung der Feinstruktur des Kalkskelettes) erfolgen unterhalb des primären Wundverschlusses, sind also nicht der Beobachtung zugängig.7. Wird der primäre Wundverschluß im ganzen vorsichtig abgehoben und zerzupft, so kann das Bewegungsverhalten der entstandenen kleinen und großen Aggregate im Durchlicht unter Z.R. untersucht werden.8. Die im zerriebenen Explantat erhaltenen Coelomzell-Aggregate aller Größen weisen erhebliche Ortsveränderungen auf; oft breiten sie sich langsam aus unter Auswanderung zehlreicher randlich liegender Zellen. An den Außenzonen mittlerer und großer Aggregate werden plasmatische Netze sichtbar, die ständig ihre Gestalt und Maschenweite ändern.9. Diese Plasma-Netze bilden die Grundlage der Aggregate; ihre Kontraktionen und Dilatationen bewirken die Ortsverlagerungen der Aggregate (Netzbildende Coelomzellen;Kuhl 1937).10. Wenigzellige Aggregate vereinigen sich in den allermeisten Fällen, sobald ein gewisser Abstand überbrückt ist. Mittlere und große Aggregate gehen häufig eine Verbindung ein; meist werden vorher lockere Coelomzell-Brücken hergestellt. In manchen Fällen gleiten die Aggregate aneinander vorbei.11. Im polarisierten Licht lassen sich bei gekreuzten Nicols die ersten kleinen neugebildeten Kalkkristalle in den skelettbildenden Coelomzellen (= netzbildenden Zellen) nachweisen.12. Der Verschluß kleiner Kratzwunden im noch dünnen primären Wundverschluß (die Kratzer dringen bis zur abgeschliffenen Skelettoberfläche vor) wird unter Z.R. im Ultropak-Auflicht untersucht. Die Ergebnisse am explantierten Wundverschluß im Durchlicht führen zum Verständnis der Bewegungsvorgänge im ungewohnten Auflicht.13. Im zunächst verwirrenden Bewegungsgeschehen (die auffälligen rotbraunen Amoebocyten haben bei der Wundheilung keine Funktion) fallen die durch die Operationsnadel herausgerissenen kleinen Kalktrümmer auf; sie werden passiv durch die Plasmanetze bewegt, gelangen auch zufällig in die Kratzer und werden an den Rändern durch neugebildetes Kalkmaterial festgelegt oder eingebaut. Aus der Tiefe der Kratzer können lose Kalkpartikel heraufbefördert werden; auch diese werden häufig eingebaut. Die entstehenden Kalkbrücken werden schließlich untereinander verbunden und dadurch die kleine Wunde verschlossen. Das eingebaute Kalkmaterial zeigt auch unter starker Z.R. keine passive Bewegung mehr.14. In seltenen Fällen kann der Vorgang des schubweisen Aufsteigens der skelettbildenden Zellen aus dem Panzer und ihre Zusammenballung im Z.R.-Laufbild beobachtet werden.15. Ob der Einbau von herausgerissenem Kalkmaterial temporär oder dauernd ist, muß noch geprüft werden.
The locomotory behaviour of coelom cells ofPsammechinus miliaris (Echinodermata) during wound-healing
In the sea urchinP. miliaris application of time lapse photography allows a study of the very slow movements of coelom cells during the healing process of small wounds on the surface of the calcareous skeleton near the periproct. For observation and time lapse photography LEITZ-Ultropak objectives were used (incident light). Ambulacral feet, spines and pedicellaria were removed, and the animal was fixed in three places in a ring of plexiglass by means of three little screws, which touched the equator of skeleton. The rate of time transformation was 1/240 to 1/480. The film reveals the behaviour of coelom cells, which move out the skeleton to the surface of the small experimental region. Within several hours the white polished surface is covered with hundreds of red-brown amoebocytes; only these are visible on the white lime-ground; they have no function in the healing process, which takes place below the surface of the primäre Wundverschluß and therefore cannot be observed. There are three main types of coelom cells: red-brown amoebocytes, körnchenführende Zellen (white amoebocytes) and leucocytes (netzbildende or skelettbildende Zellen); the flagellated cells may be neglected here. In order to be able to study the behavior of the three main types of coelom cells, the primäre Wundverschluß, i. e. the total cell-covering of the wound, is removed and torn into microscopic fragments. These are studied (time lapse) under normal optical conditions (transmitted light). The slides show many aggregates of different sizes, single cells and little calcareous concrements torn off the skeleton. The aggregates, even the big ones, exhibit slow locomotion and change their positions considerably. If the distance of two aggregates becomes small enough, they fuse. In these cases a loose cell bridge between the two aggregates is formed. Sometimes no union occurs, although the distance is very small. Even big aggregates suddenly show considerable contractions if spreading has preceded. All movements and place changing of cell-aggregates are caused by contractions and dilatations of the plasmatic network which forms the cellular basis. Little wounds in the newly built Wundverschluß scratched with a lancet, heal within several hours. Time lapse shows passive movements of small calcareous fragments, which by chance sometimes enter the small wounds, where they help and accelerate the closing of the injury. The fragments are fixed on the edge of the wound by newly produced lime. Skeleton building coelom cells (netzbildende Coelomzellen) come up in batches from the depth of the sea urchin's skeleton; each cell contains lime crystals.
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Mass spectra of underivatized hexa- and heptapeptide amides related to Substance P have been obtained with a conventional electron ionization mass spectrometer using sample vaporization from a tungsten wire by the technique of rapid heating, proton transfer ionization using ammonia, and photoplate recording of spectra. These spectra exhibit little evidence of sample pyrolysis and are readily interpreted to yield amino acid sequences.  相似文献   
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Summary Five different types of hemocytes are found within the hemolymph ofLithobius forficatus: (1) small prohemocytes, (2) very actively spreading plasmatocytes, (3) granulocytes which have a lower spreading ability but tend to agglutinate, (4) spherulocytes which are filled with spherules, and (5) presumably, a coagulocyte, characterized by instant disintegration. Cystocytes as described forL. forficatus in the literature are preparation artifacts. Cell types are characterized by electron microscopy and in vitro and vital staining techniques at the light microscopic level. Results are discussed with reference to different nomenclatures and functions of hemocytes in other arthropods.  相似文献   
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Summary The arrangement of first and second order neurons in an optic cartridge and the topographical relationships of the second order neurons within a cartridge and to groups of surrounding cartridges have been analyzed in the visual system of the bee, Apis mellifera, from light and electron microscope studies on Golgi preparations. At the level of the monopolar cell body layer, the nine retinula cell fibres of each ommatidium, the six short visual fibres arranged in a circle surrounding the three long visual fibres, become cartridges as a consequence of the appearance of the second order neurons (L-fibres) which join the R-fibre bundles. Two of the four different L-fibre types, L-1 and L-2, remain together in the centre of the cartridge throughout the lamina. The axons of the L-3 and L-4 fibres, however, have their position integrated into the circle formed by the endings of the short visual fibres. On the basis of further examination of light and especially electron microscopical Golgi material, the different L-fibres can be classified into four types which appear in each cartridge. The clear stratification in the first synaptic region (A, B and C) seems to be the best criterion for a morphological classification since such a classification necessarily also includes a functional basis. According to a naming system based on the position of the lateral processes, L-fibres with side branches in strata A, B and C are called L-1 fibres. Fibres with lateral processes in strata A and B are L-2 fibres; monopolar cell fibres with branches only in the second stratum B are L-fibres of type 3; and all monopolar cells with branches only in stratum C are called L-4 fibres. In addition to the branching pattern covering only the parent cartridge, two of the four fibre types (L-2 and L-4) have long collaterals reaching neighbouring cartridges: L-2 in stratum A and L-4 in stratum C. These collaterals presumably form a substrate for lateral interactions.  相似文献   
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Each visual unit (ommatidium) of the compound eye of the honey bee contains nine retinula cells, six of which end as axons in the first synaptic ganglion, the lamina, and three in the second optic ganglion, the medulla. A technique allowing light- and electron microscopy to be performed on the same silver-impregnated sections has made it possible to follow all types of retinula axons of one ommatidium to their terminals in order to study the shape of the terminal branches with their position in the cartridge. 1. The axons of retinula cells 1-6 (numbered according to Menzel and Snyder, 1974) end as three different types of short visual fibres (svf) in the lamina; the axons of retinula cells 7-9 run through the lamina to terminate in the medulla and are known as long visual fibres (lvf). Retinula cells of each type are identified by the location of their cell bodies and by the direction of their microvilli. The retinula cells 1 and 4 (group I according to Gribakin, 1967) end as svf type 1 with three tassel-like branches in stratum B of the first synaptic region. The pair of cells 3, 6 and the pair 2, 5 (group II) end in the first synaptic region in stratum A. Cells 3 and 6 have forked endings, svf type 2, whereas cells 2 and 5 have tapered endings, svf type 3. The remaining retinula cells 7, 8 and 9 have long fibres. Nos. 7 and 8 (group III) have tapered endings and are termed lvf types 1 and 2, respectively. The 9th cell is the lvf type 3 with a highly branched ending. 2. The nine axons in the bundle from one ommatidium have relative positions which do not change from the proximal retina to the monopolar cell body layer. 3. By following silver-stained retinula cells and their corresponding axons, it is possible to describe mirror-image arrangements of fibres in the axon bundles in different parts of the eye. This correlation of numbered retinula cells with specific axon types, together with the highly organized pattern in an axon bundle, allows the correlation between histological and physiological findings on polarization and colour perception.  相似文献   
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