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31.
Doboszyńska T Andronowska A 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2002,40(3):269-275
Abstract: Immunohistochemical localization and distribution of nitric oxide synthase (eNOS), endothelin (ET-1) and endothelin beta receptor (ETB-R) were investigated in precollector and collector lymph vessels in the broad ligament of the uterus during different phases of the estrous cycle in pigs. The polyclonal antibody for ET-1 and ETB-R and monoclonal antibody for eNOS isoform were used to perform observations on the light microscopic level. Immunoreactivities to ET-1, ETB-R and eNOS were observed in the endothelium of precollector and collector lymphangions but not in smooth muscle cells of the lymphatics examined. The staining for eNOS in the endothelial cells of all studied lymphatic vessels was stronger comparing to ET-1 and ETB-R. During the estrous cycle, only eNOS showed the correlation with the particular phases of the estrous cycle. The differences between ET-1 and ETB-R immunoreactivities were very slight and rather independent of the size or type of the lymphatic lymphangions and estrous cycle. The highest immunoreactivity level for eNOS was displayed by collector lymphangions with widened lumen in the follicular phase comparing to the precollector ones. During the luteal phase, a slight decrease in the reaction intensity was observed. The immunoreactivities for ET-1 in the endothelium of the studied vessels was not comparable with the presence or with the reactivity level of ETB-R. Optically stronger immunoreaction for ETB-R was observed in the cytoplasm of collector lymphangions in the follicular phase. eNOS, ET-1 and ETB-R were also present in the cytoplasm of the lymphatic valves. These results suggest that ET-1 and eNOS can play a role in the mechanisms regulating the vascular contractile activity, promoting lymph flow during the estrous cycle in the porcine broad ligament. 相似文献
32.
NADPH-diaphorase (NADPH-d) and an inducible type of nitric oxide synthase (iNOS) were demonstrated in porcine ovaries after unilateral infusion of bacteria into the hilus of an ovary. In group I one ml of saline was infused into the hilus of each ovary from the 15th day to the 19th day of the estrous cycle. In group II one ml of bacterial suspension (10(9) colony forming units of Escherichia coli, Staphylococcus aureus and Corynebacterium pyogenes, in a proportion 1:1:1, respectively) in saline was infused into the hilus of one ovary on days corresponding to those of the control group (gr. I), whereas saline was infused into the contralateral ovary. The ovaries were collected on the 7th day of the next estrous cycle. In the bacteria-treated ovary, the activity of NADPH-d was higher in the endothelium of blood vessels, corpora lutea and follicular walls in comparison to that observed in the respective structures of the contralateral ovary. The highest activity of NADPH-d was found in the vascular endothelium in the bacteria-infused ovary. Vascular smooth muscle cells found in both ovaries of the bacteria-treated gilts were more intensely stained for NADPH-d than those in control animals. After bacteria administration, the intensity of NADPH-d reaction in all the structures of both ovaries in group II was higher than in control group. The strongest immunostaining for iNOS was observed in all structures of the bacteria-infused ovary. In the contralateral ovary, iNOS-immunoreactivity was weaker but still stronger than that in control group. The present results revealed that infusions of bacteria into the hilus of one ovary enhanced the activity of NADPH-d and immunoreactivity for iNOS in both porcine ovaries. However, the activity of both enzymes was higher in the bacteria-infused ovary than in the contralateral one. These data suggest that locally synthesized NO can mediate an inflammatory effect of bacteria in the porcine ovaries. 相似文献
33.
Capacity and electric resistance of lipid membranes composed of lecithin and cholesterol were determined. The components were chosen for the study because they were present in biological membranes. Capacitance of the lecithin and cholesterol membranes amounts to 0.38 and 0.61 microF/cm(2), and resistance to 1.44(10(4)and 2.12(10(6)Omega cm(2), respectively. A 1:1 complex appears as a result of lecithin-cholesterol membrane formation. Parameters of the membrane formed of the lecithin-cholesterol complex were determined: surface concentration (Gamma(3)), capacitance (C(3)), and conductance (R;(3)(-1), as well as the stability constant (K) of the complex. The mean values of those magnitudes are as follows: 4.265(10(-6)mol/m(2), 0.54 microF/cm(2), 1.381(10(-6)Omega(-1)cm(-2)and 3.748(10(7), respectively. 相似文献
34.
The aim of our research was to demonstrate how the presence of EDTA affects resistance of pea plants to Pb and Pb-EDTA presence, and to show the effectivity of lead ions accumulation and translocation. It was determined that EDTA not only increased the amount of Pb taken up by plants but also Pb ion transport through the xylem and metal translocation from roots to stems and leaves. It can be seen in the presented research results that addition of the chelator with Pb limited metal phytotoxicity. We also demonstrated a significant effect of EDTA not only on Pb accumulation and metal transport to the aboveground parts but also on the profile and amount of thiol compounds: glutathione (GSH), homoglutathione (hGSH) or phytochelatins (PCs), synthesized by the plants. We observed a significant effect of the synthetic chelator on increasing the level of Pb accumulation in roots of plants treated with Pb including EDTA (0.5 and 1 mM). Pisum sativum plants treated only with 1 mM Pb(NO3)2 accumulated over 50 mg Pb x g(-1) dry wt during 4 days of cultivation. Whereas in roots of pea plants exposed to Pb+0.5 mM EDTA 35% more Pb was observed. When 1 mM EDTA was applied roots of pea accumulated over 67% more metal. The presence of EDTA also increased metal uptake and transport to the aboveground parts. In pea plants treated only with 1 mM lead nitrate less than 3 mg Pb x g(-1) dry wt was transported, whereas in P. sativum treated with Pb-EDTA doubled amount of Pb was observed in stems and leaves. 相似文献
35.
The dependence of the interfacial tension of a lipid membrane formed from phosphatidylcholine on the pH of the aqueous solution has been studied. The model describing the H(+) and OH(-) ions adsorption in the bilayer lipid surface has been presented in this work. We take suitable equations to describe the dependence of interfacial tension of a lipid bilayer membrane on H(+) and OH(-) ion concentrations. A theoretical equation is derived to describe this dependence in the whole pH range. 相似文献
36.
Lakshmiprasad Potluri Aneta Karczmarek Jolanda Verheul Andre Piette Jean‐Marc Wilkin Nadine Werth Manuel Banzhaf Waldemar Vollmer Kevin D. Young Martine Nguyen‐Distèche Tanneke Den Blaauwen 《Molecular microbiology》2010,77(2):300-323
The distribution of PBP5, the major D,D‐carboxypeptidase in Escherichia coli, was mapped by immunolabelling and by visualization of GFP fusion proteins in wild‐type cells and in mutants lacking one or more D,D‐carboxypeptidases. In addition to being scattered around the lateral envelope, PBP5 was also concentrated at nascent division sites prior to visible constriction. Inhibiting PBP2 activity (which eliminates wall elongation) shifted PBP5 to midcell, whereas inhibiting PBP3 (which aborts divisome invagination) led to the creation of PBP5 rings at positions of preseptal wall formation, implying that PBP5 localizes to areas of ongoing peptidoglycan synthesis. A PBP5(S44G) active site mutant was more evenly dispersed, indicating that localization required enzyme activity and the availability of pentapeptide substrates. Both the membrane bound and soluble forms of PBP5 converted pentapeptides to tetrapeptides in vitro and in vivo, and the enzymes accepted the same range of substrates, including sacculi, Lipid II, muropeptides and artificial substrates. However, only the membrane‐bound form localized to the developing septum and restored wild‐type rod morphology to shape defective mutants, suggesting that the two events are related. The results indicate that PBP5 localization to sites of ongoing peptidoglycan synthesis is substrate dependent and requires membrane attachment. 相似文献
37.
Girijavallabhan VM Chen L Dai C Feltz RJ Firmansjah L Li D Kim SH Kozlowski JA Lavey BJ Kosinski A Piwinski JJ Popovici-Muller J Rizvi R Rosner KE Shankar BB Shih NY Siddiqui MA Tong L Wong MK Yang DY Yang L Yu W Zhou G Guo Z Orth P Madison V Bian H Lundell D Niu X Shah H Sun J Umland S 《Bioorganic & medicinal chemistry letters》2010,20(24):7283-7287
Our research on hydantoin based TNF-α converting enzyme (TACE) inhibitors has led to an acetylene containing series that demonstrates sub-nanomolar potency (K(i)) as well as excellent activity in human whole blood. These studies led to the discovery of highly potent TACE inhibitors with good DMPK profiles. 相似文献
38.
Mojgan Shahriari Channa Keshavaiah David Scheuring Aneta Sabovljevic Peter Pimpl Rainer E. Häusler Martin Hülskamp Swen Schellmann 《The Plant journal : for cell and molecular biology》2010,64(1):71-85
The vacuole is the most prominent organelle of plant cells. Despite its importance for many physiological and developmental aspects of plant life, little is known about its biogenesis and maintenance. Here we show that Arabidopsis plants expressing a dominant‐negative version of the AAA (ATPase associated with various cellular activities) ATPase AtSKD1 (SUPPRESSOR OF K+ TRANSPORT GROWTH DEFECT1) under the control of the trichome‐specific GLABRA2 (GL2) promoter exhibit normal vacuolar development in early stages of trichome development. Shortly after its formation, however, the large central vacuole is fragmented and finally disappears completely. Secretion assays with amylase fused to the vacuolar sorting signal of Sporamin show that dominant‐negative AtSKD1 inhibits vacuolar trafficking of the reporter that is instead secreted. In addition, trichomes expressing dominant‐negative AtSKD1 frequently contain multiple nuclei. Our results suggest that AtSKD1 contributes to vacuolar protein trafficking and thereby to the maintenance of the large central vacuole of plant cells, and might play a role in cell‐cycle regulation. 相似文献
39.
Aneta Spyra 《Biologia》2010,65(4):697-703
Studies were carried out in eight woodland water bodies that are situated in an urbanised area of Southern Poland (Upper Silesia).
The aim of this study was to determine the influence of auto- and allochthonous plant detritus and exposure to sunlight on
the structure of snail communities in woodland ponds. Among some physico-chemical water parameters, pH influenced the occurrence
of snails, whereas sunlight caused an increase in diversity of the snail communities. In the total snail collection, 72.1%
of specimens were gathered in sun-exposed sites. By the same degree of insolation more preferred by snails were the sites
with allochthonic detritus. The snail fauna of subsidence ponds located inside a forest area differs from those occurring
in urban agglomerations. The most conspicuous difference is the high numbers in three woodland ponds of Hippeutis complanatus (L.), which is rare in this area. 相似文献
40.
Aneta Arct Joanna Rutkowska Rafa? Martyka Szymon M. Drobniak Mariusz Cichoń 《Biology letters》2010,6(6):762-764
The differential allocation theory predicts that females should invest more in offspring produced with attractive partners, and a number of studies support this prediction in birds. Females have been shown to increase reproductive investment when mated to males showing elaborated sexual traits. However, mate attractiveness might also depend on the interaction between male and female genotypes. Accordingly, females should invest more in offspring sired by individuals that are genetically dissimilar or carry superior alleles. Here, we show in zebra finches (Taeniopygia guttata) that pairs of unfamiliar genetic brothers and sisters are less likely to reproduce in comparison with randomly mated pairs. Among the brother–sister pairs, those that attempted to breed laid smaller clutches and of lower total clutch mass. Our results provide the first experimental evidence that females adjust their reproductive effort in response to the genetic similarity of their partners. Importantly, these results imply a female ability to assess relatedness of a social mate without prior association. 相似文献