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341.
Slawomir Tubek Andrzej Bunio Renata Szyguła Grzegorz Krasowski 《Biological trace element research》2011,140(3):253-261
The relationship between chemical elements in rainwater and the frequency of hospitalizations for gastric and duodenal peptic
ulcers was studied on the population of the province (Voivodship) of Opole, Poland, during the years 2000–2002. There is a
high positive correlation between hospitalized cases of gastric peptic ulcers with chromium in rainwater (r = 0.71), cadmium (r = 0.63), and lead (r = 0.70). Mild positive correlations were found with zinc (r = 0.55), copper (r = 0.56), iron (r = 0.57), chloride (r = 0.60), and sulfate (r = 0.52). These correlations were higher on men, suggesting that there are gender correlations involved. In duodenal peptic
ulcers, we observed a high positive correlation between chromium in rainwater and hospitalized cases (r = 0.61) and mild positive correlations with lead (r = 0.57), copper (r = 0.52), and cadmium (r = 0.51). Significant gender differences were not found. These positive correlations may be due to the biological activity
of the elements, such as their cytotoxic activity, enhanced local adrenergic stimulation on mucosal vasculature, ion channel
(mainly calcium channels) remodeling, and, for example promoting infection by Helicobacter pylori. 相似文献
342.
Renata Zuber Yiwen Wang Nicole Gehring Slawomir Bartoszewski Bernard Moussian 《Open biology》2020,10(12)
Tissue function and shape rely on the organization of the extracellular matrix (ECM) produced by the respective cells. Our understanding of the underlying molecular mechanisms is limited. Here, we show that extracellular Tweedle (Twdl) proteins in the fruit fly Drosophila melanogaster form two adjacent two-dimensional sheets underneath the cuticle surface and above a distinct layer of dityrosinylated and probably elastic proteins enwrapping the whole body. Dominant mutations in twdl genes cause ectopic spherical aggregation of Twdl proteins that recruit dityrosinylated proteins at their periphery within lower cuticle regions. These aggregates perturb parallel ridges at the surface of epidermal cells that have been demonstrated to be crucial for body shaping. In one scenario, hence, this disorientation of epidermal ridges may explain the squatty phenotype of Twdl mutant larvae. In an alternative scenario, this phenotype may be due to the depletion of the dityrosinylated and elastic layer, and the consequent weakening of cuticle resistance against the internal hydrostatic pressure. According to Barlow''s formula describing the distribution of internal pressure forces in pipes in dependence of pipe wall material properties, it follows that this reduction in turn causes lateral expansion at the expense of the antero-posterior elongation of the body. 相似文献
343.
344.
Joanna Chwiej Dariusz Adamek Magdalena Szczerbowska-Boruchowska Anna Krygowska-Wajs Slawomir Wojcik Gerald Falkenberg Anna Manka Marek Lankosz 《Journal of biological inorganic chemistry》2007,12(2):204-211
X-ray absorption near edge structure spectroscopy was applied in order to investigate differences in iron chemical state between
the nerve cells of substantia nigra (SN) representing Parkinson’s disease (PD) and those of control cases. Autopsy samples
were cut using a cryotome, and were not fixed and not embedded in paraffin. The comparison of the absorption spectra near
the iron K-edge measured in melanized neurons from SN of PD and control samples did not show significant differences in iron
oxidation state. Measurements of inorganic reference materials containing iron in the second and third oxidation states indicate
that most of the iron in all the nerve cell bodies examined was oxidized and occurred as trivalent ferric iron (Fe3+). 相似文献
345.
Slawomir Tubek Andrzej Bunio Renata Szyguła Grzegorz Krasowski 《Biological trace element research》2010,138(1-3):1-7
The elemental composition of rainwater is a suitable indirect indicator of the presence of chemical elements in airborne dust. As such, rainwater is considered a suitable monitor for environmental or natural pollution. The yearly content of chemical elements in rainwater may be considered a good indicator for determining the influence of these environmental factors on human body. We decided to investigate the relationship between chemical elements in rainwater and the frequency of hospitalizations for atrial fibrillation (I48, ICD10) on the population of the region of Opole Voivodship, Poland during the years 2000–2002. The voivodship or province has a population of one million and is divided into 12 counties that have between 44,000 and 151,000 inhabitants. We calculated the yearly average number of hospitalizations by reasons of atrial fibrillation per 10,000 inhabitants in particular counties. The average content of the chosen chemical elements in kilograms per hectare per year was calculated for each county individually and the data evaluated by means of Spearman’s correlation coefficient. There is a high positive correlation between chromium in rainwater and hospital admissions for atrial fibrillation (r?=?0.62) and mild positive correlation with cadmium (r?=?0.57), lead (r?=?0.57), zinc (r?=?0.50), and chloride (r?=?0.48). There are no significant differences between male and female patients. The biological activities of these elements, which may include enhanced adrenergic stimulation, remodeling of calcium or other ion channels, or the cytotoxic effects of hexavalent chromium may explain the positive correlations here reported. 相似文献
346.
t-RNA-nucleotidyltransferase activity was detected in Lupinus luteus seed.The enzyme was partly purified, and some of its properties are described. 相似文献
347.
348.
Daniel R. Jacobson R. Pastore Stephen Pool Slawomir Malendowicz Immaculata Kane Alia Shivji Stephen H. Embury Samir K. Ballas J. N. Buxbaum 《Human genetics》1996,98(2):236-238
The transthyretin (TTR) Ile 122 variant is associated with cardiac amyloidosis in individuals of African descent. To determine
the prevalence of the allele encoding TTR Ile 122 in African-Americans, we have used PCR and restriction analysis to test
DNA from African-Americans from various geographic areas, and found an allele frequency of 66/3376 (0.020), which is higher
than the value we previously reported in a much smaller pilot study. Our data indicate that this TTR variant is present at
equal frequency in African-Americans throughout the U.S., and suggest that this mutation may be a common, often unrecognized
cause of cardiac disease in African-Americans.
Received: 23 January 1996 相似文献