bluuebunny/crossref_metadata_2025_split huggingface dataset:
Caffeine-Induced Surface Blebbing and Budding in the Acellular Slime Mold Physarum polycephalum
Authors: Kukulies J. , Stockem W. , Wohlfarth-Bottermann K. E. 
Published: August 2018

The mechanism of plasma membrane proliferation was studied in the acellular slime mold Physarum polycephalum with the aid of light and electron microscopical techniques. Treatment of protoplasmic drops with a Tris-buffered 15 mᴍ caffeine solution causes surface blebbing and budding over periods of 5-90 min. The process of surface blebbing is coupled to a 5-10-fold increase of the surface area in conjunction with characteristic changes in cytoplasmic morphol­ogy. Successive constriction of blebs exhibiting different sizes and degree of hyalo-granuloptasmic separation leads to the formation of numerous spherical caffeine droplets. During the process of surface budding and droplet formation the total surface area of the original (genuine) protoplasmic drop is not reduced, but continues to grow.
Freeze-etch studies show that caffeine concomitantly causes characteristic changes in the fine structure of the plasma membrane. During the initial phase of surface blebbing the original density of intramembranous particles (IMP) is reduced from 3676/μm2 to 1669/μm2 and the PF:EF ratio (IMP/μm2 protoplasmic face: exoplasmic face) shifts from 2.4:1 to 2.8:1. When surface budding is completed the IMP-density in the plasma membrane of single caffeine droplets increases again to 2289/μm2 and the PF:EF ratio changes to 1.5:1. Simultaneously, the isolated caffeine droplets produce numerous small hyaline membrane protrusions, which are pinched off and contain no IMP. Control experiments demonstrate that Tris-buffer without caffeine also shows a weak capacity to induce surface blebbing, to change the IMP-density and the PF:EF ratio (2443/μm2; 1.5:1); but Tris-buffer fails to cause surface budding. On the other hand, different concentrations of sucrose (25-200 mᴍ) can supress to a certain degree both caffeine- and Tris-buffer-induced surface blebbing, but not caffeine-dependent surface budding.
The caffeine-effect is reversible insofar as protoplasmic drops with blebbing and budding activity recover to normal morphology, fine structure and locomotion when transferred to physiological conditions.
The mechanisms of successive changes in plasma membrane morphology as well as the mode of a participation of the actomyosin system in cell surface dynamics are discussed.
Energy Parameters, Macromolecular Synthesis and Cell Cycle Progression of in vitro Grown Ehrlich Ascites Tumor Cells after Inhibition of Oxydative ATP Synthesis by Oligomycin
Authors: Kroll Werner , Loffler Monika , Schneider Friedhelm 
Published: August 2018

1.In order to elucidate the significance of oxidative ATP production for the proliferation of Ehrlich ascites tumor cells, cell cycle progression, energy metabolism and macromolecular synthesis in the presence of oligomycin were studied.
2.In the presence of the inhibitor (20 μ/ml), lactate production and glucose uptake of the cells increased by about 30-35% as compared to controls; oxygen consumption was maximally inhibited by 30-45% and could not further be reduced by higher concentrations of the inhibitor. ATP/ADP ratios of the oligomycin treated cells and control cells were not significantly different.
3.In the first passage in the presence of oligomycin proliferation of the cells is reduced to about 50% that of controls; without severely affecting viability (dye exclusion test). In the second passage with oligomycin cell proliferation completely arrests. As was shown by flow cytometric analysis and BrdU-H33258 technique of flow cytometry, cells accumulate in the early S phase; division of cells which are in the S- and G 2 M compartment at the beginning of oligomycin treatment accounts for the increase of cell number in the first passage in the presence of oligomycin. On recultivation in the third passage in the absence of the inhibitor cells take up proliferation again; an increase of cell number of about 60% of controls was observed within 24 h.
4.In the presence of oligomycin incorporation of [2-l4C]thymidine is reduced to about 20% of the controls within 8 h. incorporation of [U-l4C]lysine begins to slow down immediately after treatment with the inhibitor, the same is true for the incorporation of [2-14C]uridine. Transport of α-aminoisobutyric acid into the cells is not severely affected.
5.It is suggested, that not lack of energy by inhibition of oxidative phosphorylation accounts for the arrest of cell cycle progression in the presence of oligomycin but rather the blockade of transport of cytoplasmatic (glycolytic) ATP into mitochondria, which is caused by the high potential built up across the mitochondrial membrane in the presence of this inhibitor.
Transient Activation of the Ca2+-ATPase from Sarcoplasmic Reticulum during Thiol Modification by 5 ,5′-Dithiobis(2-nitrobenzoate)
Authors: Swoboda Gertrude , Hasselbach Wilhelm 
Published: August 2018

In the reaction of sarcoplasmic reticulum m em branes with excess 5,5′-dithiobis(2-nitrobenzoate) (DTNB) some new features were observed:
1) The Ca2+-dependent ATPase activities of increasingly modified preparations were considerably enhanced during the initial stage of thiol blockage. A maximum (130 -160% of the control activity) was reached when about 1.5 - 2 mol thiol groups per 105 g vesicular protein had reacted, in the absence of ATP and detergent. At higher extents of modification inactivation occurred. Purified ATPase behaved principally similar to native sarcoplasmic vesicles.
2) In the presence of Mg2+ and ATP the activity maxim um (up to 180% of control) was broadened and shifted towards a higher degree of thiol blockage. Concomitantly the modification and inactivation rates were considerably reduced.
3) Glycerol (10 -30 % , v/v) slightly enhanced the ATPase activity maximum and reduced the rate of inactivation essentially only by decreasing the DTNB modification rate.
4) In the presence of sufficient myristoylglycerophosphocholine for solubilization no activation was observed.
5) The steady state level of phosphoprotein from ATP was raised to about 150% of the control level 10 s after addition of DTNB (about 1/2 thiol blocked), followed by a linear decrease with the number of thiols labeled, while the Ca2+-dependent ATPase activity of preparations modified under equivalent conditions (10-4 м Ca2+ and 2 x 10-3 м Mg2+ present) showed a broader maximum corresponding to 1.5 thiols blocked.
Phosphorylation of Ca-ATPase of Sarcoplasmic Reticulum with Different Substrates
Authors: Barrabin Hector , Meis Leopoldo de 
Published: August 2018

ATP and GTP as substrate for phosphorylation of sarcoplasmic reticulum ATPase are compared. Maximal levels of phosphoenzyme are between 4.5 and 4.8 nmol per mg of protein when either substrate is used provided that phosphoenzyme hydrolysis are strongly inhibited by high calcium concentration (20 mм) and low temperatures ( 0 ° C ) . The maximal values obtained with GTP are lower than those previously reported.
It is shown that this difference is due to underestimation of the specific activity of labeled nucleotides used in previous studies, as revealed by UV absorption and HPLC analysis.
The dependence of the phosphoenzyme levels on calcium concentration, pH and temperature confirm previous findings indicating that ATP, but no GTP, accelerates the rate limiting step of the catalytic cycle.
Comparison of Diuron-and Phenol-Type Inhibitors: Additional Inhibitory Action at the Photosystem II Donor Site
Authors: Pfister Klaus , Schreiber Ulrich 
Published: August 2018

Inhibitors of photosystem II reactions from the “diuron-type” and “phenol-type” have been compared regarding their mechanism of action.
“Diuron-” as well as “phenol-type” inhibitors act at the acceptor site of photosystem II by displacing the secondary acceptor quinone Qв from its binding site.
“Phenol-type” inhibitors additionally interfere with the donor site, which is demonstrated in studies of chlorophyll fluorescence and luminescence. This mechanism of action is shown to be similar but not identical to that reported for hydroxylamine.
New Dextrorotatory Pterocarpan Phytoalexins from Leaflets of Nissolia fruticosa
Authors: Ingham John L. 
Published: August 2018

Abstract
Three isoflavonoid phytoalexins produced by the fungus or CuSO4-treated leaflets of Nissolia fruticosa have been identified as (+)-6aS; 1 la S-3.7-dihydroxy-9-methoxypterocarpan (nissicarpin). (+)-6 aS ; 1 la S-7-hydroxy-3,9-dimethoxypterocarpan (fruticarp in) and (+)-6a.S; 11 aS-3,7-dihydroxy-2,9-dimethoxypterocarpan (nissolicarpin).
Elaboration of the 6,7,8 Oxygenation Pattern in Simple Coumarins: Biosynthesis of Puberulin in Agathosma puberula Fourc
Authors: Brown Stewart A. , Rivett D. E. A. , Thompson H. Joan 
Published: August 2018

Abstract
Umbelliferone and scopoletin are well utilized as precursors of puberulin, a 7-O-prenyl ether of isofraxidin elaborated by Agathosm a puberula Fourc. (Rutaceae). As ferulic, sinapic, and caffeic acids were all more poorly utilized than 4′-hydroxycinnamic (p-coumaric) acid, the partial biosynthetic route: 4′-hydroxycinnamic acid →→ um belliferone → aesculetin → scopoletin →→ puberulin is suggested as the major pathway. Prenylether formation apparently occurs at or beyond the scopoletin stage. The implication that ferulic acid does not participate in the formation of scopoletin from 4′-hydroxycinnamic acid is at variance with the known role of ferulic acid as a scopoletin precursor in tobacco.
Identification of N1–Glycolylbiuret in the Gamma Radiolysis of Aerated Aqueous Solution of Cytosine. Influence of the pH
Authors: Polverelli Michel , Ulrich Jacques , Teoule Robert 
Published: August 2018

Abstract
N1 Glycolylbiuret, pH-Effect N1 glycolylbiuret has been identified as a radiation product of cytosine in aerated aqueous solution at pH 4.5. When varying the pH of the solution before irradiation from acidic values towards neutral ones. G value of N1 glycolylbiuret reached a maximum at pH 4.5.
Effects of N-Aryl-N’ ,N’ -Dialkyl-1,2-Ethanediainines on ATP Formation in Chloroplasts. QSAR of Amine Uncouplers
Authors: Berg Gerard van den , Brandse Marjo 
Published: August 2018

Abstract
The effects of the algicide PH 40-62 on photosynthetic reactions in spinach chloroplasts were studied. The compound proved to be an uncoupler of photophosphorylation, whereas inhibition of photosynthetic electron transport occurred at higher concentrations. The site of this inhibition was before photosystem II. The uncoupling effect was partially reversible. In a series of related compounds the uncoupling activity appeared mainly dependent on the lipophilic properties of the compounds but electronic effects also played a distinct role. Comparing these uncoupling data with those of some known series of uncouplers it appeared that lipophilicity determines the uncoupling activity in an identical way and a regression equation was found describing the uncoupling activities of 60 compounds belonging to four chemically different groups of com pounds.
The Life Span and Osmotic Fragility of Erythrocytes in Mice Bearing Benzo(a) Pvrene — Induced Fibrosarcoma
Authors: Ray M. R. , Chowdhury J. Roy 
Published: August 2018

Abstract
Erythrocyte Survival. Osmotic Fragility, Fibrosarcom a Red cell survival studies in mice with benzo(a) pyrene [B(a)p]-induced fibrosarcoma indicate marked reduction in RBC 51Cr rW2. In contrast, the t w2 of erythrocytes from B(a)p injected but tumor-free mice was not declined. Increasing tumor burden resulted in increment in the severity of this disorder, and preincubation of normal red cells with tumor supernatant caused significant reduction (p < 0.05) in 51Cr t > /2 . It is suggested that the observed alteration in RBC life span may be due to the effect of tumor. Apparently, both intrinsic and extrinsic cellular defects could be implicated for this abnormality. However, the shortened survival cannot be attributed to altered osmotic fragility, since the erythrocytes of the fibro-sarcomatous mice were more resistant to hypotonic hemolysis in vitro.
Isolation of the Products Resulting from the Reaction of cis and trans Diaminedichloroplatinum [II] with DNA and Chromatin on the Dowex 50 W Column
Authors: Olinski Ryszard , Walter Zofia 
Published: August 2018

Abstract
The production of platinated derivatives of nucleic acid bases resulting from the reaction of cis and trans DDP with DNA and chrom atin was studied.
Bifunctional complex of guanine appeared to be the major product of the interaction of cis isomer with both DNA and chromatin, although other bifunctional adducts of A-Pt-G and A-Pt-A were also isolated. The main product of the interaction of trans DDP with DNA was a monofunctional adduct of guanine. Small amounts of the bifunctional complexes were also isolated. When ssDNA was incubated with trans DDP more bifunctional complexes appeared, what suggests that geometric constrains of double helix prevent formation of these complexes. Trans isomer reacts more easily with chromosomal proteins than cis DDP does. Therefore after the reaction of trans DDP with chromatin less platination occurs on DNA moieties.
Red-Light Effects Sensitized by Methylene Blue on Nitrate Reductase from Spinach (Spinacia oleracea L.) Leaves
Authors: Mauriño S. G. , Vargas M. A. , Aparicio P. J. , Maldonado J. M. 
Published: August 2018

Abstract
Nitrate reductase from spinach (Spinacia oleracea L.) leaves, which had been inactivated in vitro by incubation with NADH and cyanide, was fully reactivated in minutes when irradiated in anaerobic conditions with red light in the presence of methylene blue. Both the rate and the extent of reactivation increased with light intensity (6 to 100 W·m-2) and dye concentration (1 to 10 μM). On the contrary, photoreactivation was completely abolished when NADH or ethylenediaminetetra-acetic acid were present during irradiation. We propose that methylene blue, when photo excited, exhibits a redox potential positive enough to reoxidise the CN--re-duced molybdenum complex settled in the inactive enzyme, thus causing its reactivation.
On the other hand, prolonged irradiation of nitrate reductase, under air and in the presence of methylene blue, promoted an oxygen-dependent irreversible inactivation of the two partial activities of the enzyme. This inactivation was markedly enhanced in 77% deuterated water and greatly prevented by azide, which indicates that singlet oxygen is the species primarily involved in the photooxidative inactivation of the enzyme.
Flash Photolysis of Liposomes Containing Chlorophyll and Zeaxanthin, as a Function of Temperature (2 °-34 °C)
Authors: Brody Seymour Steven 
Published: August 2018

Abstract
The transfer of triplet excitation from chlorophyll to zeaxanthin in liposomes is a function of temperature and pigment concentration.
At 525 nm both chlorophyll and zeaxanthin triplet states are observed. The result is a biphasic increase in absorption. The rise time of absorption by the chlorophyll triplet is much faster, than by the zeaxanthin triplet. With increasing temperature the contribution of absorption by zea­xanthin (relative to that of chlorophyll) at 525 nm increases, and its rise time gets faster. At high ratios of zeaxanthin to chlorophyll, temperature has less effect on both the rise time and absorption by the zeaxanthin triplet state.
The chlorophyll triplet is measured at 780 nm. It decays faster with increasing temperature and or increasing ratio of zeaxanthin to chlorophyll.
The results are interpreted in terms of: increasing fluidity of the lipid liposome with temper­ature, formation of zeaxanthin-chlorophyll complexes at high ratios of zeaxanthin and chloro­phyll, presence of different lipid phases in the liposome bilayer.
Flavonoids of Ericameria laricifolia (Asteraceae)
Authors: Clark W. Dennis , Wollenweber Eckhard 
Published: August 2018

Abstract
Nineteen flavonoid aglycones have been identified from the external stem and leaf resin of Ericameria laricifolia by thin layer co-chromatography with authentic samples. Kaempferol, quercetin, apigenin, and their methyl ethers have been found, along with luteolin and 6-methoxy luteolin. It is suggested that future flavonoid chemosys-tematic studied of resin-exuding species would best focus on aglycones as opposed to glycosides.
The Composition of Terpene Hydrocarbons in the Essential Oils from Leaves of Four Cistus Species
Authors: Gülz Paul-Gerhard , Kobold Uwe , Michaelis Karl , Vostrowsky Otto 
Published: August 2018

Abstract
The hydrocarbon fractions of the essential oils from leaves of Cistus ladanifer, C. palhinhae, C. laurifolius and C. monspeliensis were analysed by GLC and GCMS techniques.
Novel Epicuticular Leaf Flavonoids from Kalmia and Gaidtheria (Ericaceae)
Authors: Wollenweber Eckhard , Kohorst Gisela 
Published: August 2018

Abstract
Leaves of a number of Ericaceous plants have a thin epicuticular layer that consists mostly of triterpenes. In Kalmia angustifolia, K. latifolia and K. polifolia as well as in Gaultheria procumbens and G. shallon this material also contains trace amounts of flavonoid aglycones. In Kalmia they are the 3-OMe-derivatives of four C-methyl flavones reported previously as the typical leaf-wax flavonoids of Eucalyptus. The new compounds, 5-OH-3,7,4′-triOMe-6,8-diCH3-flavone (kalmiatin), 5-OH-3,7,4′-triOMe-6-CH3-flavone (8-desmethyl-kalmiatin), 5,4′-diOH-3,7-diOMe-6,8-diCH3-flavone (latifolin) and 5,4′-diOH-3,7-diOMe-6-CH3-flavone (8-desmethyl-latifolin) are novel natural products. They could not be detected in eight species of Eucalyptus. A screening of 15 species of Ericaceae revealed that 8-desmethyl-sideroxylin and 8-desmethyl-latifolin are present also in the epicuticular layer on leaves of Gaultheria procumbens, while on G. shallon and on Andromeda polifolia traces of galangin-3-methyl ether were found. In the other species checked no external flavonoid aglycones could be detected.
Die Entladung der Haptocysten von Ephelota gemmipara (Suctoria, Ciliata) / Mode of Discharge of Haptocysts in Ephelota gemmipara (Suctoria, Ciliata)
Authors: Benwitz Gertrud 
Published: August 2018

Abstract
The fine structure of haptocysts, characteristic organelles of most suctorians, is described during the resting state and the discharge after contact with the prey. In Ephelota, there is no fusion of the plasma membranes of predator and prey, as has been suggested for the haptocysts of other suctorians. But the membrane covering the organelle becomes continuous with the plasma membrane of the suctorian tentacle, and inner structures of the haptocyst attach to the perforated pellicle of the prey.
Das radialpolare Differenzierungsmuster bei Trichoplax adhaerens F. E. Schulze (Placozoa) / The Radial Polar Pattern of Differentiation in Trichoplax adhaerens F. E. Schulze (Placozoa)
Authors: Schwartz Viktor 
Published: August 2018

Abstract
In contrast with the outmost uniform aspect of Trichoplax there is a clear cut differentiation between marginal and central cell territories. Dissection and transplantation as well as vital staining show that the marginal material is restricted to a seam approximately 20 μm in width, surrounding the much larger mass of central cells. Isolated marginal or central cell material can not regenerate a complete individual and is therefore doomed to die. Regeneration requires the presence of both components because the cells propagate true to type only, meeting the Ruthmann model (A Ruthmann, Cytobiol. 15, 58 (1977)). There is no redifferentiation between marginal and central cells. Marginal pieces transplanted into the central area produce an inverted inner edge, surrounding an open hole. Dissection or transplantation borne frag­ments containing sufficient cells of both marginal and central provenience reassort their cells to the normal relative position. Unbalanced compositions of fragments may be regulated by detachment of surplus material or (in the case of marginal surplus) also by fission, even in very small individuals. This way fission is involved in the regulation of the quantitative relation between these two kinds of cells. A monstrous modification of the shape and physiologic properties demonstrates a disturbance of these regulations. The marginal versus central differentiation manifests a radial polarity, till now unknown as to the relation to the histologically discerned cell types.
Notizen: The Pheromone Receptor System of Male Eulia ministrana L., with Notes on Other Cnephasiini Moths
Authors: Priesner Ernst 
Published: August 2018

Abstract
The antennal Sensilla trichodea of male Eulia ministrana (Tortricidae: Cnephasiini) contain specialist receptor cells for the sex-attractant components (Z)-9-and (Z)-11-tetra-decenyl acetate and the attraction-inhibitors (E)-11 -tetra-decenyl acetate, (Z)-7-dodecenyl acetate, and (Z)-11 -hexa-decenyl acetate. The significance of the latter two compounds as potential sex pheromone components in Tortri­cidae is considered.
Notizen: Isolation and Respiratory Assay of Earthworm Body Wall Mitochondria
Authors: Rao T. V. , Biswal U. C. 
Published: August 2018

Abstract
Out of several media tested, KCl medium containing BSA was found to be most suitable for isolation of functionally efficient mitochondria from earthworms. Respiration and oxidative phosphorylation in isolated mitochondria are demonstrated in the presence of cytochrome c and BSA in reaction medium.
Introduction - The details of the respiratory metabolism in earthworm are yet to be established. There are only a few contradictory reports on the nature of its respiratory enzyme components [1]. While, cytochrome oxidase, succinoxidase, succinate dehydrogenase were identified in earthworm tissue homogenates, the presence of Kreb′s cycle enzymes could not be demonstrated. Very little information is available on earthworm mitochondria except one report where it is isolated in 0.44 ᴍ mannitol [2]. Mitochondria from invertebrates like insects and crustaceans are isolated and characterized [3, 4]. But such methods cannot be extended to earthworms as it is known that conditions for isolation and assay of mitochondria are highly system specific [5].
Notizen: Neuroanatomical Evidence for Electroreception in Lampreys
Authors: Fritzsch Bemd , Caprona M .-Dominique Crapon de , Wächtler Klaus , Körtje Karl-Heinz 
Published: August 2018

Abstract
The patterns of the anterior lateral-line afferents of Lampetra fluviatilis as revealed by transganglionic trans­port of horseradish peroxidase are described. The afferents form two roots in entering the rhombencephalon. Fibers of the dorsalmost root can be traced to a short dorsal fascicle which runs along the dorsal nucleus. The ventral roots form two fascicles adjacent to the nucleus intermedius. Comparison with urodeles indicates that lampreys, like urodeles and other anamniotic vertebrates are electroreceptive.