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Zancani M Bertolini A Petrussa E Krajňáková J Piccolo A Spaccini R Vianello A 《Journal of plant physiology》2011,168(11):1226-1233
Embryogenic cell masses (ECM) of Abies cephalonica were grown on proliferation media in the presence and absence of fulvic acid (FA), whose molecular composition and conformational rigidity were evaluated by CPMAS-13C NMR spectroscopy. To assess the physiological effects of this humic material during proliferation and maturation stages of somatic embryogenesis (SE), proliferation rate, proportion of consecutive developmental stages of pro-embryogenic masses (PEM), cellular ATP and glucose-6-phosphate were evaluated at regular intervals. FA increased the proliferation rate, especially during the early sampling days, and the percentage of PEM in their advanced developmental stage. Cellular ATP and glucose-6-phospahte were increased by FA pre-treatment during the maturation phase. Furthermore, the effects of the anti-auxin p-chlorophenoxyisobutyric acid (PCIB), such as a decrease of growth and the enhancement of PEM III induction, were inverted by FA. Proton pumping ATPase and PPase activities were decreased in microsomes from PCIB-treated ECM, while they increased in the presence of FA. This fulvic matter also induced a delay in somatic embryo formation during the maturation phase. Both the improvement of the PEM proliferation and the reduction of the subsequent maturation process of A. cephalonica are explained by a release from the complex humic structure of low molecular-weight molecules, which may interact with the plant hormonal signaling pathway. These effects appear to be related to the hydrophilic and conformationally labile nature of FA. The structure-activity relationship observed here suggests that the influence of FA on ECM may be attributed to specific bioactive molecules that are preferentially released from the FA loose superstructure. 相似文献
64.
Kraj M Kopeć-Szlęzak J Pogłód R Kruk B 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(1):168-182
The aim of this prospective study was to define the flow cytometric characteristics of simultaneously investigated bone marrow and peripheral blood plasma cells antigens expression in 36 plasma cell leukemia (PCL) patients. The immunophenotypic profile of plasma cells was determined with a panel of monoclonal antibodies. The antigen expression intensity was calculated as relative fluorescence intensity (RFI). Bone marrow plasma cells showed expression of particular antigens in the following proportion of cases: CD49d 100%, CD29 94%, CD54 93%, CD44 83%, CD56 60%, CD18 26%, CD11b 29%, CD11a 19%, CD117 27%, CD71 30%, CD126 100% and CD19 0%, while the expression of those antigens on peripheral blood plasma cells was present in the following percentage of patients: CD49d 100%, CD29 96%, CD54 93%, CD44 95%, CD56 56%, CD18 50%, CD11b 53%, CD11a 29%, CD117 26%, CD71 28%, CD126 100% and CD19 0%. The expression of CD54 was significantly higher than that of adhesion molecules belonging to the integrin b2 family: CD11a, CD18 and CD11b, on both bone marrow and peripheral blood cells (p < 0.01). Expression of CD18, CD11a and CD11b was differential between two cell compartments: lower on bone marrow and higher on peripheral blood cells. We found that plasma cells in the bone marrow of patients with plasma cell leukaemia showed significantly greater granularity and size than those in the peripheral blood (p = 0.0001 and p = 0.04, respectively). However, no differences in cell size or granularity were revealed between bone marrow plasma cells from patients with PCL and multiple myeloma. In conclusion, impaired expression of adhesion molecules such as CD11a/CD18 (LFA-1) or CD56 may explain hematogenic dissemination characterizing PCL. The following pattern of adhesion molecule expression according to the proportion of plasma cells expressing a given antigen in peripheral blood and bone marrow and arranged in diminishing order may be established: CD49d > CD44 > CD54 > CD29 > CD56 > CD18 > CD11b > CD11a. Immuno-phenotyping of plasma cells in PCL, as in multiple myeloma, might be useful in detecting minimal residual disease in cases with aberrant antigen expression and for selecting therapeutic agents towards specific membrane targets. 相似文献
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Vanda Repiská Ivan Varga Ivan Lehocky Daniel B?hmer Milan Bla?ko ?tefan Polák Marián Adamkov ?ubo? Dani?ovi? 《Biologia》2010,65(5):919-924
In the present study, human neonatal fibroblasts were isolated from a two-month-old human male. The purpose of the present
investigation was the analysis of the morphology (light and transmission electron microscopy), karyotype and growth characteristics
of the human neonatal fibroblast cell culture B-HNF-1. Moreover, STR typing and mitochondrial DNA amplification and sequencing
was also performed. Analysis of chromosomes count showed that B-HNF-1 cell culture is diploid and has normal male karyotype
46, XY, which was stable during cultivation. The transmission electron microscopy demonstrated the ultra-structure of the
B-HNF-1 cells; they have typical morphological features of proteosynthesis-active cells. Large number of fibroblasts bearing
different shapes and surface characteristics adhered to the substrate with microvilli and filopodia. Our in vitro expanded
fibroblasts have a large and irregular nucleus with prevalence of euchromatin. One to three nucleoli are present in each nucleus.
The cytoplasm contains a richly developed rough endoplasmic reticulum and prominent Golgi apparatus cisterns. The result of
the fragment analysis is a DNA profile defined as multiplex of STR markers and sex determining system. Sequencing analysis
of hypervariable segments of control region of mitochondrial DNA showed haplotype that belongs to haplogroup W. In this study,
we complexly characterized a new cell culture of human neonatal fibroblasts B-HNF-1 from different points of view. This culture
should be used for further biomedical experiments. 相似文献
67.
J. Velemínská L. Bigoni V. Krajíček J. Borský D. Šmahelová V. Cagáňová M. Peterka 《HOMO》2012,63(2):81-93
Sexual dimorphism is responsible for a substantial part of human facial variability, the study of which is essential for many scientific fields ranging from evolution to special biomedical topics. Our aim was to analyse the relationship between size variability and shape facial variability of sexual traits in the young adult Central European population and to construct average surface models of adult males and females. The method of geometric morphometrics allowed not only the identification of dimorphic traits, but also the evaluation of static allometry and the visualisation of sexual facial differences.Facial variability in the studied sample was characterised by a strong relationship between facial size and shape of sexual dimorphic traits. Large size of face was associated with facial elongation and vice versa. Regarding shape sexual dimorphic traits, a wide, vaulted and high forehead in combination with a narrow and gracile lower face were typical for females. Variability in shape dimorphic traits was smaller in females compared to males. For female classification, shape sexual dimorphic traits are more important, while for males the stronger association is with face size.Males generally had a closer inter-orbital distance and a deeper position of the eyes in relation to the facial plane, a larger and wider straight nose and nostrils, and more massive lower face. Using pseudo-colour maps to provide a detailed schematic representation of the geometrical differences between the sexes, we attempted to clarify the reasons underlying the development of such differences. 相似文献
68.
The presence of Foxp3(+) regulatory CD4(+) T cells in tumor lesions is considered one of the major causes of ineffective immune response in cancer. It is not clear whether intratumoral T(reg) cells represent T(reg) cells pre-existing in healthy mice, or arise from tumor-specific effector CD4(+) T cells and thus representing adaptive T(reg) cells. The generation of T(reg) population in tumors could be further complicated by recent evidence showing that both in humans and mice the peripheral population of T(reg) cells is heterogenous and consists of subsets which may differentially respond to tumor-derived antigens. We have studied T(reg) cells in cancer in experimental mice that express naturally selected, polyclonal repertoire of CD4(+) T cells and which preserve the heterogeneity of the T(reg) population. The majority of T(reg) cells present in healthy mice maintained a stable suppressor phenotype, expressed high level of Foxp3 and an exclusive set of TCRs not used by naive CD4(+) T cells. A small T(reg) subset, utilized TCRs shared with effector T cells and expressed a lower level of Foxp3. We show that response to tumor-derived antigens induced efficient clonal recruitment and expansion of antigen-specific effector and T(reg) cells. However, the population of T(reg) cells in tumors was dominated by cells expressing TCRs shared with effector CD4(+) T cells. In contrast, T(reg) cells expressing an exclusive set of TCRs, that dominate in healthy mice, accounted for only a small fraction of all T(reg) cells in tumor lesions. Our results suggest that the T(reg) repertoire in tumors is generated by conversion of effector CD4(+) T cells or expansion of a minor subset of T(reg) cells. In conclusion, successful cancer immunotherapy may depend on the ability to block upregulation of Foxp3 in effector CD4(+) T cells and/or selectively inhibiting the expansion of a minor T(reg) subset. 相似文献
69.
Vojniković B Strenja-Linić I Ivancić A Synek S Mićović V Bajek G 《Collegium antropologicum》2010,34(Z2):185-189
This paper is focused on disease Amaurosis Fugax (AF), indicating the necessary urgent therapy in attack of illnesses. In attack, the patient represents ophthalmic case, because of vision lost, but primary process and cause exists even earlier and very often is of chronical character. Authors emphasize sequencing in therapy of AF and accentuate that in 24 hours the cause of the disease may be defined. AF is a syndrome with very different etiopathogenesis, including also big complexity in diagnosis and therapy. 相似文献
70.
Some evolutionary explanations of cross-cultural differences propose that human personality is caused by pathogen stress. Both xenophobia and ethnocentrism evolved under conditions with high parasite prevalence. Further, inter-individual variation in disgust or fear of parasites is expected to be influenced by human health, where healthy people should express lower disgust sensitivity to parasites. We examined inter-individual variation of children’s fear, disgust and self-perceived danger between two distinct cultures differing in overall pathogen prevalence. We found that children were able to distinguish between disease-relevant and disease-irrelevant groups of invertebrates and that children in regions with high pathogen prevalence expressed greater fear, disgust and self-perceived danger of all animals, irrespective of disease threat. After controlling for confounding factors, better health of children was associated with lower perceived danger of disease-relevant animals. Gender differences were found only in conditions with low pathogen stress. Our results support the idea that cross-cultural differences in human perception of animals are mediated by pathogen threat. Further research is necessary to investigate causal relationship between human health and avoidance of potentially hazardous animals. 相似文献