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271.
Mucopolysaccharidoses (MPS) are inherited metabolic diseases from the group of lysosomal storage disorders (LSD). They are caused by genetic defects resulting in the absence or severe deficiency in one of lysosmal hydrolases involved in degradation of glycosaminoglycans (GAG). Partially degraded GAGs are accumulated in lysosomes, causing dysfunction of cells, tissues and organs. Last years did bring some breakthrough discoveries, which were important to understand biochemical mechanisms of MPS appearance and course, as well as to develop therapeutic procedures for these inherited metabolic disorders. 相似文献
272.
273.
Celestyna Mila-Kierzenkowska Alina Wo?niakTomasz Boraczyński Alicja JureckaBeata Augustyńska Bartosz Wo?niak 《Journal of thermal biology》2011,36(1):29-33
In this study higher activity of certain lysosomal enzymes with concomitant lower α1-antitryspin activity was revealed in serum of kayaker women after intense exercise without any external stimuli as compared with the exercise preceded by extreme cold application. Whole-body cryostimulation may have hormetic, beneficial impact on reduction of muscle damage. 相似文献
274.
Staphylococcal cysteine proteases are implicated as virulence factors in human and avian infections. Human strains of Staphylococcus aureus secrete two cysteine proteases (staphopains A and B), whereas avian strains express staphopain C (ScpA2), which is distinct from both human homologues. Here, we describe probable reasons why the horizontal transfer of a plasmid encoding staphopain C between avian and human strains has never been observed. The human plasma serine protease inhibitor α1-antichymotrypsin (ACHT) inhibits ScpA2. Together with the lack of ScpA2 inhibition by chicken plasma, these data may explain the exclusively avian occurrence of ScpA2. We also clarify the mechanistic details of this unusual cross-class inhibition. Analysis of mutated ACHT variants revealed that the cleavage of the Leu383-Ser384 peptide bond results in ScpA2 inhibition, whereas hydrolysis of the preceding peptide bond leads to ACHT inactivation. This evidence is consistent with the suicide-substrate-like mechanism of inhibition. 相似文献
275.
276.
Marciniak P Kuczer M Rosinski G 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2011,181(6):721-730
Three neuropeptides Zopat-MS-2 (pEDVDHVFLRFa), Zopat-SK-1 (pETSDDYGHLRFa) and Zopat-NVPL-4trunc. (GRWGGFA), recently isolated
from the neuroendocrine system of the Zophobas atratus beetle, were tested for their myotropic and hyperglycaemic activities in this species. These peptides exerted differentiated
dose-dependent and tissue specific physiological effects. Zopat-MS-2 inhibited contractions of the isolated heart, ejaculatory
duct, oviduct and hindgut of adult beetles and induced bimodal effects in the heart contractile activity of pupae in vivo.
It also increased the haemolymph free sugar level in larvae of this species, apart from myotropic activity. Zopat-SK-1 showed
myostimulatory action on the isolated hindgut of the adult beetles, but it decreased contractions of the heart, ejaculatory
duct and oviduct. Injections of this peptide at a dose of 2 μg also caused delayed cardioinhibitory effects on the heartbeat
of the pupae. Together with the ability to increase free sugar level in the haemolymph of larvae these were new physiological
activities of sulfakinins in insects. Zopat-NVPL-4trunc. inhibited the muscle contractions of the two organs: hindgut and
ejaculatory duct but it was inactive on the oviduct and the heart of the adult beetles. This peptide also increased free sugar
level concentration in the haemolymph of Z. atratus larvae. These physiological actions are the first biological activities discovered for this group of the insect peptides.
The present work showed pleiotropic activity of three neuropeptides and indicates that the visceral muscle contractions and
the haemolymph sugar homeostasis in Z. atratus are regulated by complex mechanisms. 相似文献
277.
Marzec-Wróblewska U Kamiński P Lakota P Szymański M Wasilow K Ludwikowski G Kuligowska-Prusińska M Odrowąż-Sypniewska G Stuczyński T Michałkiewicz J 《Biological trace element research》2011,143(1):167-177
The aim of the present study was to measure zinc (Zn) and iron (Fe) concentration in human semen and superoxide dismutase
(SOD) activity in seminal plasma and correlate the results with sperm quality. Semen samples were obtained from men (N = 168) undergoing routine infertility evaluation. The study design included two groups based on the ejaculate parameters.
Group I (n = 39) consisted of males with normal ejaculate (normozoospermia), and group II (n = 129) consisted of males with pathological spermiogram. Seminal Zn and Fe were measured in 162 samples (group I, n = 38; group II, n = 124) and SOD activity in 149 samples (group I, n = 37; group II, n = 112). Correlations were found between SOD activity and Fe and Zn concentration, and between Fe and Zn concentration. SOD
activity was negatively associated with volume of semen and positively associated with rapid progressive motility, nonprogressive
motility, and concentration. Negative correlation was stated between Fe concentration and normal morphology. Mean SOD activity
in seminal plasma of semen from men of group I was higher than in seminal plasma of semen from men of group II. Fe concentration
was higher in teratozoospermic males than in males with normal morphology of spermatozoa in group II. Our results suggest
that Fe may influence spermatozoa morphology. 相似文献
278.
Kozłowski M Naumnik W Nikliński J Milewski R Lapuć G Laudański J 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(1):90-97
The discovery of markers to lymphatic endothelial cells and the development of novel antibodies to these markers have brought increasing attention to the lymphatics and progress in the understanding of lymphangiogenesis and cancer metastasis. In this study, we investigate the presence of lymphatic vessel invasion (LVI) detected by D2-40 immunohistochemical staining in resected esophageal cancer and correlated with clinicopathologic data and patient survival. Sixty nine patients, who had a primary resection of esophageal cancer, were analyzed by univariate and multivariate logistic regression, and univariate and multivariate survival analysis. The total rate of LVI was 72% (50/69). Positive LVI was significantly correlated with lymph node metastasis (p < 0.001), tumor size (p < 0.001), histological grading (p = 0.017), tumor depth (p = 0.001), and stage (p < 0.001). Multivariate logistic analysis identified LVI (p = 0.036) as a predictor of regional lymph node metastasis. On univariate survival analysis, patients with LVI had a significantly shorter disease-free survival, cancer-specific survival and overall survival. Multivariate analysis proved that LVI diagnosed by D2-40 is an independent prognostic factor of both disease-free survival (p = 0.04) and overall survival (p = 0.032) in resected esophageal cancer. These results show that LVI assessment identifies patients at high risk for regional lymph node metastasis and that LVI is an independent prognostic factor in patients with esophageal cancer. 相似文献
279.
Zaninetti R Fornarelli A Ciarletta M Lim D Caldarelli A Pirali T Cariboni A Owsianik G Nilius B Canonico PL Distasi C Genazzani AA 《Journal of neurochemistry》2011,116(4):606-615
Calcium is a universal signal, and its capacity to encode intracellular messages via spatial, temporal and amplitude characteristics allows it to participate in most cellular events. In a specific context, calcium plays a pivotal role in migration, although its role has not been elucidated fully. By using immortalized gonadotropin-releasing hormone-secreting neurons (GN11), we have now investigated the role of TRPV4, a member of the vanilloid family of Ca(2+) channels, in neuronal migration. Our results show that TRPV4 channels are present and functional in GN11 cells and their localization is polarized and enriched in lamellipodial structures. TRPV4 activation leads to a retraction of the lamellipodia and to a decrease in migratory behaviour; moreover cells migrate slower and in a more random manner. We therefore provide evidence for a new regulation of gonadotropin-releasing hormone neurons and a new role for calcium at the leading edge of migratory cells. 相似文献
280.
Listeria monocytogenes strains isolated from clinical food and environmental samples were genotyped by Restriction Enzyme Analysis with Pulsed Field Gel Electrophoresis (REA-PFGE) using ApaI and AscI enzymes according to PulseNet Europe procedure. Analysis of DNA fragments profiles obtained by AscI digestion demonstrated presence of 62 REA-PFGE profiles grouped in 2 lineages (FI, FII). Diversity of strains source among both lineages was observed. Statistical analysis showed, that strains isolated from clinical samples more frequently are included to lineage FI, then lineage FII. Non-clinical strains were more frequently included to lineage FII. Combined analysis of REA-PFGE profiles for ApaI and AscI enzymes showed 8 unique pulsotypes characteristic for two or more L. monocytogenes isolates. Moreover researched L. monocytogenes strains were analyzed by multiplex-PCR according Doumith et al methodology. PCR-group 4B was most frequent among strains isolated from clinical samples. Correlation between PCR-group and pulsotype was observed only in few cases. 相似文献