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271.
Bartosz Kazimierz Słowikowski Margarita Lianeri Paweł Piotr Jagodziński 《Molecular biology reports》2017,44(1):35-50
It is well known that a connection between xenobiotics inhalation, especially tobacco combustion and Lung Cancer development is strongly significant and indisputable. However, recent studies provide evidence indicating that another factors such as, estrogens are also involved in lung carcinoma biology and metabolism. Although the status of estrogen receptors (ER), in both cancerous and healthy lung tissue has been well documented, there is still inconclusive data with respect of which isoform of the receptor is present in the lungs. However according to several studies, ERβ appears to be predominant form. Apart from ERs, estrogens can work through a recently discovered G-coupled estrogen receptor. Binding with both types of the receptors causes a signal, which leads to i.e. enhanced cell proliferation. There are many published reports which suggest that estrogen can be synthesized in situ in lung cancer. Some disturbances in the activity and expression levels of enzymes involved in estrogen synthesis were proved. This suggests that increased amounts of sex-steroid hormones can affect cells biology and be the reason of the accelerated development and pathogenesis of lung cancer. There also exist phenomena which associate estrogenic metabolism and tobacco combustion and its carcinogenic influence on the lungs. Compounds present in cigarette smoke induce the activity of CYP1B1, the enzyme responsible for estrogenic metabolism and synthesis of their cateholic derivatives. These structures during their redox cycle are able to release reactive oxygen species or form DNA adduct, which generally leads to destruction of genetic material. This process may explain the synergistic effect of smoking and estrogens on estrogen-dependent lung cancer development. 相似文献
272.
Aleksandra Wilk Barbara Wiszniewska Dagmara Szypulska-Koziarska Paulina Kaczmarek Maciej Romanowski Jacek Różański Marcin Słojewski Kazimierz Ciechanowski Małgorzata Marchelek-Myśliwiec Elżbieta Kalisińska 《Biological trace element research》2017,175(1):1-9
This study evaluated serum and hair mineral and trace element levels as well as levels of other nutritional factors affecting growth and appetite in young children with non-organic failure to thrive (NOFTT) based on the presence or types of feeding difficulty (FD). Between August 2012 and July 2015, 136 children less than 6 years of age with NOFTT were included. FD was diagnosed based on Wolfson criteria and divided into subtypes according to Chatoor’s classification. Clinical data were reviewed, and serum and hair mineral levels were measured. Of all assessed serum and hair minerals, only hair sulfur contents differed significantly between subjects with and without infantile anorexia (39,392 ± 2211 vs. 40,332 ± 2551 μg/g, P = 0.034). There were no differences in serum and hair mineral levels between children with and without sensory food aversion. Hair copper contents were significantly lower in children with FD of reciprocity (12.3 ± 6.0 vs. 22.4 ± 25.1 μg/g, P = 0.049). While hair zinc contents were also lower, the difference was not statistically significant (49.2 ± 26.8 vs. 70.6 ± 41.0 μg/g, P = 0.055). Only hair manganese contents were significantly lower in children with posttraumatic FD (0.12 ± 0.04 vs. 0.26 ± 0.73 μg/g, P = 0.037). In conclusion, there were no differences in most serum and hair mineral levels in children with NOFTT, except for relatively lower hair levels of sulfur, copper and possibly zinc, and manganese in infantile anorexia, reciprocity, and posttraumatic types of FD, respectively. 相似文献
273.
Bożena Pawlikowska-Pawlěga Kazimierz Trěbacz Elżbieta Król Antoni Gawron 《Acta Physiologiae Plantarum》2000,22(1):61-67
Quercetin is a very common flavonoid widely distributed in many plants. The flavonoid intake has been linked to the prevention
of human diseases including cancer. Flavonoids possess also a broad spectrum of effects on plants. Quercetin is involved in
Ca2+ transport and metabolism. The present study was designed to check the effects of quercetin alone and in combination with
verapamil on the resting and action potentials in the liverwort Conocephalum conicum. The application of 59·10−6 mol·dm−3 quercetin caused an increase of action potential amplitudes. During the 3rd and 4th hour of treatment an increase by 20–22
% with respect to the control was observed. No changes were found in the resting potential in quercetin treated plants. Verapamil,
a calcium channel inhibitor, caused gradual decrease of action potential amplitudes. Quercetin, when added together with verapamil,
prevented its inhibitory effect. Interactions between quercetin and Ca2+ transport are discussed. 相似文献
274.
275.
Jaroslaw Baran Monika Baj-Krzyworzeka Kazimierz Weglarczyk Rafal Szatanek Maria Zembala Jakub Barbasz Antoni Czupryna Antoni Szczepanik Marek Zembala 《Cancer immunology, immunotherapy : CII》2010,59(6):841-850
Cell membrane microfragments called microvesicles (MV) originating from different cells are circulating in the blood of healthy
subjects and their elevated numbers are found in different diseases, including cancer. This study was designed to characterise
MV present in plasma of gastric cancer patients. Since majority of MV in blood are platelets-derived (PMV), plasma samples
deprived of PMV were used. In comparison to control, the number of MV in patients was significantly elevated in all stages,
higher in more advanced disease. Patients’ MV showed an increased membrane expression of CCR6 and HER-2/neu. The proportion
of MV carrying some leucocyte determinants was low and similar in patients and control. Transmission electron microscopy showed
their substantial heterogeneity in size and shape. The size determined by dynamic light scattering analysis confirmed this
heterogeneity. The MV size distribution in patients was broader within the range of 10–800 nm, while in control MV showed
3-mode distribution within the range of 10–400 nm. Atomic force microscopy confirmed MV size heterogeneity with implication
that larger objects represented aggregates of smaller microparticles. Patients’ MV exhibited increased absolute values of
zeta potential, indicating a higher surface charge. Tumour markers HER-2/neu, MAGE-1, c-MET and EMMPRIN were detected both
in control and patients’ samples with stronger expression in the latter. Significantly higher expression of MAGE-1 and HER-2/neu
mRNA was observed in individual patients. All together, it suggests that at least some MV in plasma of gastric cancer patients
are tumour-derived. However, their role in cancer requires further studies. 相似文献
276.
277.
Systematic investigations of the influence of various temperatures of exposure on the autoradiographic efficiency and on the rate of fogging of Kodak AR 10 stripping film were carried out. The oxygen content and humidity of the exposed autoradiographs as well as the time of exposure were constant. Exposure of autoradiographs or storage of film at room temperature caused an increase of overall autoradiographic efficiency by approximately 40%, but although the rate of film fogging was also increased, it did not exceed the safe values of background. Both autoradiographic efficiency and rate of fogging were not altered significantly when a temperature of 4 C or -18 C for exposure was used. Therefore, room temperature of exposure is recommended for ordinary autoradiography. For a special autoradiographic technic when low temperature of exposure has to be used, the temperature -18 C may be safely applied without significant impairment of autoradiographic efficiency. 相似文献
278.
Geovanny I. Nic-Can Rosa M. Galaz-ávalos Clelia De-la-Pe?a Armando Alcazar-Maga?a Kazimierz Wrobel Víctor M. Loyola-Vargas 《PloS one》2015,10(6)
Somatic embryogenesis is a powerful biotechnological tool for the mass production of economically important cultivars. Due to the cellular totipotency of plants, somatic cells under appropriate conditions are able to develop a complete functional embryo. During the induction of somatic embryogenesis, there are different factors involved in the success or failure of the somatic embryogenesis response. Among these factors, the origin of the explant, the culture medium and the in vitro environmental conditions have been the most studied. However, the secretion of molecules into the media has not been fully addressed. We found that the somatic embryogenesis of Coffea canephora, a highly direct embryogenic species, is disrupted by the metabolites secreted from C. arabica, a poorly direct embryogenic species. These metabolites also affect DNA methylation. Our results show that the abundance of two major phenolic compounds, caffeine and chlorogenic acid, are responsible for inhibiting somatic embryogenesis in C. canephora. 相似文献
279.
Novel mutation in the BMPR1B gene (R486L) in a polish family and further delineation of the phenotypic features of BMPR1B‐Related brachydactyly
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280.
Jian Zhang Yi Fu Kazimierz Nowaczyk Joseph R. Lakowicz 《Biochemical and biophysical research communications》2010,400(1):111-116
Chemokine receptor 5 (CCR5) is a cell surface protein required for HIV-1 infection. It is important to detect the amount and observe the spatial distribution of the CCR5 receptors on the cell surfaces. In this report, we describes the metal nanoparticles which were specially designed as molecular fluorescent probes for imaging of CCR5 receptors on the T-lymphocytic PM1 cell surfaces. These CCR5 monoclonal antibodies (mAbs) metal complexes were prepared by labeling mAbs with Alexa Fluor 680 followed by covalent binding the labeled mAbs on the 20 nm silver nanoparticles. Compared with the labeled mAbs without metal, the mAb-metal complexes were found to display enhanced emission intensity and shortened lifetime due to interactions between fluorophores and metal. The mAb-metal complexes were incubated with the PM1 cell lines. The confocal fluorescent intensity and lifetime cell images were recorded on single cells. It was observed that the mAb-metal complexes could be clearly distinguished from the cellular autofluorescence. By analyzing a pool of cell images, we observed that most CCR5 receptors appeared as clusters on the cell surfaces. The fluorophore-metal complexes developed in this report are generally useful for detection of cell surface receptors and provide a new class of probe to study the interaction between the CCR5 receptors with viral gp120 during HIV infections. 相似文献