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101.
Macronuclear differentiation in conjugating pairs of Tetrahymena treated with the antitubulin drug nocodazole 总被引:2,自引:0,他引:2
Andrzej Kaczanowski Malgorzata Ramel Janina Kaczanowska Denys Wheatley 《Experimental cell research》1991,195(2):330-337
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. 相似文献
102.
The effects of amphotericin B on lipid metabolism in cultured human skin fibroblasts 总被引:4,自引:0,他引:4
Richard A. Levy Richard E. Ostlund Jr. Janina Brajtburg 《In vitro cellular & developmental biology. Plant》1985,21(1):26-31
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. 相似文献
103.
104.
105.
Janina Jakubowska-Gabara 《Plant Ecology》1996,124(1):45-59
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 相似文献
106.
Janina Kulka Borbála Székely Lilla V. Lukács Orsolya Kiss Anna-Mária T?kés Eszter Vincze Eszter Turányi János Fillinger Zoltán Hanzély Gabriella Arató Miklós Szendr?i Balázs Gy?rffy A. Marcell Szász 《The journal of histochemistry and cytochemistry》2016,64(4):256-267
Parallel studies of primary breast carcinomas and corresponding distant metastases samples reveal considerable differences. Our aim was to highlight this issue from another perspective and provide further data based on 98 patient samples: 69 primary breast carcinoma and 85 distant metastases from bone, central nervous system (CNS) and lung (56 paired). Two independent series of immunohistochemical reactions with different antibodies for estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor 2 (Her2), along with HER2 fluroscence in situ hybridization (FISH) were performed on tissue microarrays to classify breast carcinoma and distant metastases samples into Luminal A, Luminal B-proliferating, Luminal B-HER2+, HER2+ and triple negative (TNBC) surrogate breast cancer groups. Correlation and agreement between the two assessments of ER and PgR were fair-to-moderate, and almost perfect for HER2 and Ki67. There was 40% discordance concerning immunophenotype between breast carcinomas and distant metastases. Most common metastatic site of ER+ breast carcinoma was the skeletal system (59.2%), whereas that of TNBCs was the CNS (58.8%) and lungs (23.5%). Distant metastases in bones were mostly luminal (54.3%), in the CNS, Luminal B (53.2%), and in the lung, TNBC (37.5%). The change of drugable properties of primary breast cancers in the respective bone and CNS metastases suggests that characterization of the metastasis is necessary for appropriate treatment planning. 相似文献
107.
Phenology of cryptomonads and the CRY1 lineage in a coastal brackish lagoon (Vistula Lagoon,Baltic Sea) 下载免费PDF全文
Kasia Piwosz Janina Kownacka Anetta Ameryk Mariusz Zalewski Jakob Pernthaler 《Journal of phycology》2016,52(4):626-637
Cryptomonadales have acquired their plastids by secondary endosymbiosis. A novel clade—CRY1—has been discovered at the base of the Cryptomonadales tree, but it remains unknown whether it contains plastids. Cryptomonadales are also an important component of phytoplankton assemblages. However, they cannot be readily identified in fixed samples, and knowledge on dynamics and distribution of specific taxa is scarce. We investigated the phenology of the CRY1 lineage, three cryptomonadales clades and a species Proteomonas sulcata in a brackish lagoon of the Baltic Sea (salinity 0.3–3.9) using fluorescence in situ hybridization. A newly design probe revealed that specimens of the CRY1 lineage were aplastidic. This adds evidence against the chromalveolate hypothesis, and suggests that the evolution of cryptomonadales’ plastids might have been shorter than is currently assumed. The CRY1 lineage was the most abundant cryptomonad clade in the lagoon. All of the studied cryptomonads peaked in spring at the most freshwater station, except for P. sulcata that peaked in summer and autumn. Salinity and concentration of dissolved inorganic nitrogen most significantly affected their distribution and dynamics. Our findings contribute to the ecology and evolution of cryptomonads, and may advance understanding of evolutionary relationships within the eukaryotic tree of life. 相似文献
108.
Katja Schneider Andreas Schiermeyer Anja Dolls Natalie Koch Denise Herwartz Janina Kirchhoff Rainer Fischer Sean M. Russell Zehui Cao David R. Corbin Lakshmi Sastry‐Dent W. Michael Ainley Steven R. Webb Helga Schinkel Stefan Schillberg 《Plant biotechnology journal》2016,14(4):1151-1160
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. 相似文献
109.
Inga Dziembowska Paweł Izdebski Anna Rasmus Janina Brudny Marta Grzelczak Piotr Cysewski 《Applied psychophysiology and biofeedback》2016,41(2):141-150
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. 相似文献
110.
Thorben Sprink Janina Metje Joachim Schiemann Frank Hartung 《Plant biotechnology reports》2016,10(6):345-351
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. 相似文献