Platinum(II) complexes with 2,4-diaminobutyric acid,ornithine, lysine and 4,5-diaminovaleric acid

L-2,4-Diaminobutyric acid (Dab) reacts with K₂PtCl₄ yielding PtCl₂(N,O-Dab), which rearranges to PtCl₂(N,N-Dab). Reaction with L-ornithine and L-lysine yields the corresponding PtCl₂(N,O-Orn) and PtCl₂(N,O-Lys), respectively, whereas reaction with 4,5-diaminovaleric acid (Dav) yields PtCl₂(N,N- Dav).     

Macronuclear differentiation in conjugating pairs of Tetrahymena treated with the antitubulin drug nocodazole

During Tetrahymena conjugation gamic nuclei (pronuclei) are produced, reciprocally exchanged, and fused in each mate. The synkaryon divides twice; the two anterior nuclei develop into new macronuclei while the two posterior nuclei become micronuclei. The postzygotic divisions were blocked with the antitubulin drug nocodazole (ND). Then pronuclei (gamic nuclei) developed directly into macronuclear anlagen (primordial macronuclei), inducing amicronucleate cells with two anlagen, or, rarely, cells with one anlagen and one micronucleus. ND had a similar effect on cells that passed the first postzygotic division inducing amicronucleate cells with two anlagen, while cells treated with ND at the synkarya stage produced only one large anlage. Different intracytoplasmic positioning of the nuclei treated with ND (pronuclei, synkarya and two products of the first division) shows that most of cell cytoplasm is competent for inducing macronuclear development. Only posteriorly positioned nuclei--products of the second postzygotic division--remain micronuclei. The total cell DNA content, measured cytophotometrically in control and in ND-induced amicronucleate conjugant cells with one and two anlagen, was similar in all three samples at 12 h of conjugation. Eventually, at 24 h this content was about 2 pg (8 C) per anlagen both in nonrefed control and in amicronucleate exconjugants. Therefore "large" nuclei developing in the presence of ND were true macronuclear anlagen.     

The effects of amphotericin B on lipid metabolism in cultured human skin fibroblasts

Summary Amphotericin B inhibits hydroxymethylglutarylcoenzyme A (HMGCoA) reductase activity and incorporation of [³H]acetate into sterols and fatty acids of human skin fibroblasts. Delivery of cholesterol to cells via the low density lipoprotein receptor pathway is not altered. The effects of amphotericin B on cell lipid metabolism are partially reversed by both potassium and insulin. Portions of this work were presented at the Southern Regional Meeting of the American Federation for Clinical Research, January 1983.     

Decline of Potentillo albae-Quercetum Libb. 1933 phytocoenoses in Poland

The historical process of the decline of the thermophilous oak forest was studied at 11 selected localities within the whole area of the association in Poland. The comparative analysis of phytosociological data from the periods of 1929–1981 and 1987–1991 has shown the total decline of Potentillo albae-Quercetum at nine localities as well as symptoms of regression at two localities. It has been stated that in Eastern Pomerania and in Greater Poland in the places of Potentillo albae-Quercetum phytocoenoses the communities of Galio-Carpinetum and Calamagrostio-Quercetum have appeared. In the central, north-east, south-east and southern part of the country, the thermophilous oak forest has changed into Tilio-Carpinetum phytocoenoses. The results of the study indicate that the recession of Potentillo albae-Quercetum is taking place in the whole area of the association in Poland. The size of the area is changing, the number of localities is decreasing. The consequence of the thermophilous oak forest decline is the unification and impoverishment of woodland vegetation and flora. These localities of the association which exist up to date are refuges for many interesting helio- and thermophilous species. Their presence to a great extent determines the genetic pool and diversity of Polish flora.Abbreviations Acc accompanying - FB Festuco-Brometea - Fg Fagetalia sylvaticae - MA Molinio-Arrhenatheretea - QF Querco-Fagetea - Qp Quercetalia pubescentis - SN Sedo-Scleranthetea and Nardo-Callunetea - TG Trifolio-Geranietea sanguinei - VP Vaccinio-Piceetea     

Targeted gene exchange in plant cells mediated by a zinc finger nuclease double cut

Genome modification by homology‐directed repair (HDR) is an attractive tool for the controlled genetic manipulation of plants. Here, we report the HDR‐mediated gene exchange of expression cassettes in tobacco BY‐2 cells using a designed zinc finger nuclease (ZFN). The target contained a 7‐kb fragment flanked by two ZFN cutting sites. That fragment was replaced with a 4‐kb donor cassette, which integrates gene markers for selection (kanamycin resistance) and for scoring targeting (red fluorescent protein, RFP). Candidates resulting from cassette exchange were identified by molecular analysis of calli generated by transformation via direct DNA delivery. The precision of HDR‐mediated donor integration was evaluated by Southern blot analysis, sequencing of the integration locus and analysis of RFP fluorescence by flow cytometry. Screening of 1326 kanamycin‐resistant calli yielded 18 HDR events, 16 of which had a perfect cassette exchange at the insert junction and 13 of which produced functional RFP. Our results demonstrate that ZFN‐based HDR can be used for high frequency, precise, targeted exchange of fragments of sizes that are commercially relevant in plants.     

Effects of Heart Rate Variability Biofeedback on EEG Alpha Asymmetry and Anxiety Symptoms in Male Athletes: A Pilot Study

Heart rate variability biofeedback (HRV-BFB) has been shown as useful tool to manage stress in various populations. The present study was designed to investigate whether the biofeedback-based stress management tool consisting of rhythmic breathing, actively self-generated positive emotions and a portable biofeedback device induce changes in athletes’ HRV, EEG patterns, and self-reported anxiety and self-esteem. The study involved 41 healthy male athletes, aged 16–21 (mean 18.34 ± 1.36) years. Participants were randomly divided into two groups: biofeedback and control. Athletes in the biofeedback group received HRV biofeedback training, athletes in the control group didn’t receive any intervention. During the randomized controlled trial (days 0–21), the mean anxiety score declined significantly for the intervention group (change-4 p < 0.001) but not for the control group (p = 0.817). In addition, as compared to the control, athletes in biofeedback group showed substantial and statistically significant improvement in heart rate variability indices and changes in power spectra of both theta and alpha brain waves, and alpha asymmetry. These changes suggest better self-control in the central nervous system and better flexibility of the autonomic nervous system in the group that received biofeedback training. A HRV biofeedback-based stress management tool may be beneficial for stress reduction for young male athletes.     

Plant genome editing in the European Union—to be or not to be—a GMO

New plant-breeding techniques have been boosting plant breeding, since only a few years but already first promising products are pushing to the market. In contrast to this, in many countries, the current Directives regulating genetically modified organisms have been established more than 25 years ago, especially in the European Union being based on clear differentiation between transgenic plants and conventional breeding. Therefore, the question arises if these Directives are suitable to face the new challenge of genetic engineering or if there is a need for updated regulations.     

Some growth responses of apple seedlings to abscisic acid and growth stimulators

Antonovka seedlings were obtained from the embryos soaked in abscisic acid (ABA) alone, gibberellin A₄₊₇, benzyladenine or the mixtures of these regulators. The inhibitory effect of ABA on the growth of the seedlings was of temporary duration. The height of the 12 week-old seedlings was dependent only on the degree of seed after-ripening and not on the ABA treatment. The growth stimulators studied were unable to overcome the inhibitory effect of ABA observed in the early stages of seedling growth. The growth stimulators did not substitute, for cold treatment of apple seeds which is the only treatment so far known to overcome the dwarf conditions of the seedlings obtained from non-after-ripened embryos. ABA greatly suppressed the early stages of apple seedling growth (up to 6 weeks) during which they resembled physiological dwarfs. The highest concentrations of ABA (2·0 μg ml^?1) greatly modified the root system of the seedlings, and produced a larger percentage of seedlings with unbranched roots.