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1.
Krystyna Golinska 《Protoplasma》1988,147(2-3):125-134
Summary Microtubular organelles formed during continuous exposure to high or low temperature were studied. Neither heat nor cold prevents formation of the microtubular skeleton in the oral parts of the ciliateDileptus. Elevated temperature causes the formation of short microtubular fibres, while the size of the oral structure is not diminished. This leads to failure in sculpturing of the cytostome. Heat-treatment may also alter the localization of the anchor site of fibres around the circumference of the basal bodies, and the orientation of the fibres. Cold-treatment evokes the formation of small mouthparts containing a lower number of organelles, although these are properly shaped and there are no deviations in the position or orientation of fibres. It seems that low temperature may suppress the rate of formation of microtubular organelles, while elevated temperature affects their patterning.Abbreviations MTOC
microtubule organizing centre
- T
transverse fibres
- B
basal body
- Cy
cytostome
- K
kinetodesma
- P
postciliary fibre
- C
compound fibre
- L
lamina
- F
filamentous bundle
- M
monokinetid 相似文献
2.
Ewa Nizankowska Angelita Q. Sheridan Marie H. Maile Carol J. Cross Rafal Nizankowski Krystyna Prochowska Andrew Szczeklik 《Prostaglandins & other lipid mediators》1985,29(3):349-362
We evaluated in a double-blind study the bronchodilatory properties of 2-decarboxy-2-hydroxymethyl prostaglandin E1 (PGE1-carbinol), described recently as a nonirritant bronchodilator in animals. Fifteen asthmatic patients received by inhalation single doses of 1, 10, and 30 μg PGE1-carbinol, 55 μg PGE2, and placebo (10% ethanol in normal saline, which was also used as diluent for the PGs). Such pulmonary function tests as forced expiratory volume in 1 second, forced vital capacity, and maximal expiratory flow were monitored during 2 hours following inhalation of each compound. 10 and 30 μg PGE1-carbinol produced significant but short-acting bronchodilation, similar to that caused by 55 μg PGE2. One-third of the patients reported mild cough and throat irritation during and shortly after inhalation of 30 μg PGE1-carbinol or 55 μg PGE2. Placebo and 1 μg PGE1-carbinol produced minimal side effects, but neither agent caused bronchodilation. In an adjunctive, unblinded trial, the same patients received 400 μg fenoterol. Fenoterol caused greater bronchodilation 15 and 30 minutes after inhalation than did the PGs in the double-blind study. 相似文献
3.
Sea urchins have elaborated multiple defenses to assure monospermic fertilization. In this work, we have concentrated on a study of the mechanism(s) by which hydrogen peroxide (H2O2) prevents polyspermy in Arbacia punctulata. We found that it is not H2O2 but probably hypochlorous acid/hypochlorite (HOCl/OCl?) derived from H2O2 that is toxic to the supernumerary sperm. The spermicidal activity of H2O2 is potentiated by at least one order of magnitude by cupric ions (Cu2+). This increased toxicity is not due to the formation of hydroxyl radicals (·OH) because ·OH scavengers did not counteract the activity of Cu2+. More-over, substitution of Cu2+ by ferrous ions (Fe2+), which are known to cause formation of ·OH from H2O2, had no effect on fertilization even at 102?103 times higher concentrations. In contrast, 3-amino-1,2,4-triazole (AT), an HOCl/OCl? scavenger, totally reversed the toxic effects of Cu2+. Furthermore, we found that HOCl/OCl? is generated in solutions of H2O2 and Cu2+ in the presence of 0.5 M NaCl and that its accumulation is abolished by AT. Thus it is possible that the antifertility properties of copper are due to its ability to mediate formation of HOCl/OCl?. HOCl/OCl? generated by Cu2+ from H2O2 and Cl?, a low concentration of exogenously added HOCl/OCl?, or increased concentrations of H2O2 has similar inhibitory effects on the fertilization process in sea urchins. Therefore, we suggest that polyspermy is prevented by the action of a myeloperoxidase that affects the formation of HOCl/OCl? from the Cl? present in sea water through reaction with H2O2 generated by the newly fertilized egg. 相似文献
4.
Jan Zarzycki Alina Peryt Barbara Klubińska Teresa Hajac Krystyna Żak 《Histochemistry and cell biology》1969,18(4):314-320
Zusammenfassung Es wurden mit histochemischen Methoden Milchdrüsen von Meerschweinchen in physiologischer und durch Kastration während der Laktationsperiode hervorgerufener Involution untersucht. Nachgewiesen wurden alkalische und saure Phosphatase (APh und SPh), unspezifische Esterase, Sukzinodehydrase, SH-Gruppen, Nukleinsäuren und Lipide. — Die Aktivität der SPh nimmt während der Involution zu. Die Bedeutung dieses Enzyms für den Rückbildungsprozeß des Drüsengewebes wird diskutiert. — Das Vorkommen der APh-Aktivität in Drüsenendstücken im Involutionsstadium kann auf die Beteiligung dieses Enzyms an der Rückresorption der mit der Milch ausgeschiedenen Substanzen hinweisen. — Zwischen der Aktivität der unspezifischen Esterase und dem Gehalt sowie der Lokalisation von Lipiden besteht eine Abhängigkeit. — Es konnten keine Unterschiede in der Sukzinodehydraseaktivität und dem DNS-Gehalt aufgezeigt werden. — Die Verminderung von SH-Gruppen und RNS hängt mit dem Aufhören der Sekretionsproduktion durch die Zellen der Drüsenendstücke der Milchdrüsen zusammen.
Histochemical studies on the involution mechanism of the mammary gland
Summary Histochemical methods were used to study mammary glands of guinea pigs in the course of physiologic involution and that induced by castration during lactation. Alkaline and acid phosphatases, unspecific esterase, succinic dehydrogenase, SH groups, nucleic acids and lipids were determined. Acid phosphatase activity was found to be increased in mammary glands, subject to involution. The participation of the enzyme in the involutionary process of the gland tissue is discussed. The distribution of alkaline phosphatase in the secretory sections of the gland during involution would suggest the participation of the enzyme in the reabsorption of the substance secreted with milk. A correlation existing between the activity of unspecific esterase, the level and distribution of lipids in the mammary gland could be established. No differences were detected in the activity of succinic dehydrogenase and DNA level. A decrease in SH groups and RNA content is related to cessation of milk secretion.相似文献
5.
1-acid glycoprotein (AGP) is a serum acute phase glycoprotein which possesses five N-linked complex type heteroglycan side chains which may be present as bi-, tri- and tetraantennary structures. Depending upon the content of biantennary structure on AGP, up to four glycoforms of AGP are present in serum. These glycoforms can be easily estimated in body fluids by means of crossed affinity-immunoelectrophoresis (CAIE) with the lectin, Concanavalin A (Con A). Con A selectively binds biantennary structures; the more biantennary structures on AGP, the stronger the binding. In acute inflammation, a relative increase of AGP glycoforms with biantennary units is observed - a type I glycosylation change. In some chronic inflammatory states there is an relative decrease of AGP glycoforms with biantennary heteroglycans — a type II glycosylation change. Moreover, in certain other states such as pregnancy, estrogen administration or liver damage, type II glycosylation changes are also seen. A detailed analysis of the clinical applications of the assessment of AGP glycoforms in sera of patients with rheumatic diseases, AIDS and various types of cancers is presented. Accumulated data shows that AGP glycoforms may be very useful in the detection of intercurrent infections in the course of rheumatoid arthritis, systemic lupus erythematosus, or myeloblastic leukaemia, and in the detection of secondary infections in human immunodeficiency virus infected individuals. AGP glycoforms are also very useful in differentiation between various forms of trophoblastic disease and are helpful in monitoring the treatment of these patients. Finally, AGP glycoforms provide valuable information for differentiation between primary and secondary liver cancer. 相似文献
6.
Danuta Sosnowska Andrzej Mysliwski Krystyna Dzierzbicka Aleksander M. Kolodziejczyk 《Biotherapy》1997,10(2):161-168
The modulation of NK activity by muramyl dipeptides derivatives against Ab (amelanotic) Bomirski melanoma and human erythroleukemia
K562 cells was studied in vitro. The stimulatory effect was observed for 3 of 7 muramyl dipeptides: MDP(L-Ala)C921, MDPC857
and L18-MDP(Ala) in relation to cytotoxic activity of NK cells obtained from peripheral blood and spleen of healthy and Ab
Bomirski melanoma bearing hamsters. An increased of cytotoxic activity NK cells isolated from animals before and during the
transplantable phase of the tumor against K562 was found. A similar stimulation was received for NK cells obtained from animals
against their own melanoma cells. The most significant influence of examined MDP derivatives on the cytotoxic activity of
NK cells were obtained from animals between 10 to 12 days of tumor growth. The extent of the modulation of cytotoxic activity
of NK cells was dependent on its initial value both in healthy control and Ab Bomirski melanoma bearing hamsters. If natural
cytotoxic activity was high the stimulatory effect of the examined MDP derivatives was only slightly expressed. 相似文献
7.
Krystyna Harmata 《Vegetation History and Archaeobotany》1995,4(4):235-243
The pollen diagram from Tarnowiec concentrates on human impact on vegetation, and is supported by the archaeological background. The earliest evidence of human activities dated at ca. 6500 B.P. was probably connected with the Neolithic Linearbandkeramik culture. Further periods of settlement are recorded at ca. 5200 B.P. and at 4800 B.P. The next very distinct period of intensification in human impact at ca. 4200-3800 B.P. was most certainly connected with the presence of the Corded Ware culture. The next period of settlement occurred during the late Bronze Age, in connection with the development of the Lusatian culture from ca. 3200 B.P. but is recorded only faintly in the pollen diagram. The next colonization phase at ca. 2600 B.P. is possibly the result of Scythian invasions. The widest expansion of human impact came during the period of Roman influence. After this, anthropogenic indicators decreased during the Migration period. The youngest part of the pollen diagram reveals an intensification of anthropogenic indicators connected with early Medieval settlement. 相似文献
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10.
Siv Osterman-Golkar Antti Kautiainen Emma Bergmark Krystyna Hkansson Jorma Mki-Paakkanen 《Chemico-biological interactions》1991,80(3):291-302
Binding of 1,2-epoxy-3-butene, the primary metabolite of butadiene, to hemoglobin (Hb) and excretion of its mercapturic acid in urine were studies as potential indicators of butadiene exposure. Four groups of Wistar rats were exposed to butadiene at 0, 250, 500 and 1000 ppm 6 h/day, 5 days/week, during 2 weeks. Blood was collected at the end of exposure and 17 days later for analysis of hemoglobin adducts and adduct stability. Urine was collected each day during exposure (afternoon samples) and in between exposures (morning samples). Adducts of 1,2-epoxy-3-butene to N-terminal valine in Hb were measured using the N-alkyl Edman procedure and GC/MS of the thiohydantoin derivatives. The corresponding mercapturic acid was analysed, after deacetylation, through derivatization with phthaldialdehyde and HPLC with fluorescence detection. The Hb adducts proved to be stable and are therefore useful for dosimetry of long-term exposure to butadiene. The adduct levels increased linearly with exposure dose up to 1000 ppm (3 nmol/g Hb at 1000 ppm). The increase with exposure dose of the mercapturic acid concentration in urine was also compatible with a linear does response up to 1000 ppm. The sensitivity of both analytical methods needs to be improved for their application to human samples. 相似文献