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11.
Olszewski WL Jain P Ambujam G Zaleska M Cakala M Gradalski T 《Lymphatic research and biology》2011,9(2):77-83
Background: Physiotherapy of edema in cases with obstructed main lymphatics of lower limbs requires knowledge of how high external pressures should be applied manually or set in compression devices in order to generate tissue pressures high enough to move tissue fluid to nonswollen regions and to measure its flow rate. Methods: We measured tissue fluid pressure and flow in subcutaneous tissue of lymphedematous limbs stages II to IV at rest and during pneumatic compression under various pressures and inflation timing. An 8-chamber sequential compression device inflated to pressures 50-120?mmHg, for 50 sec each chamber, with no distal deflation, was used. Pressures were measured using a wick-in-needle and electronic manometer. Fluid flow was calculated from continuously recorded changes in limb circumference using strain gauge plethysmography. Results: Before massage, in all stages of lymphedema, stagnant tissue fluid pressures in subcutaneous tissue ranged between -1 and +10 mmHg and did not differ from those measured in normal subjects. Pressures generated in tissue fluid by pneumatic compression reached 40-100 mmHg and were lower than those in inflated chambers. High pressure gradient through the skin was caused by its rigidity (fibrosis) and dissipation of applied compression force to proximal noncompressed limb regions. The calculated volumes of displaced tissue fluid ranged from 10 to 30 ml per compression cycle, to reach in some cases 100 ml in the groin region. Conclusions: Tissue fluid pressures generated by a pneumatic device were found lower than in the compression chambers. The obtained results point to the necessity of applying high pressures and longer compression times to generate effective tissue fluid pressures and to provide enough time for moving the stagnant fluid. 相似文献
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Rafał Krętowski Anna Stypułkowska Marzanna Cechowska-Pasko 《Molecular and cellular biochemistry》2015,398(1-2):165-173
The inhibition of the 26S proteasome evokes endoplasmic reticulum stress, which has been shown to be implicated in the antitumoral effects of proteasome inhibitors. The cellular and molecular effects of the proteasome inhibitor—bortezomib—on human colon cancer cells are as yet poorly characterized. Bortezomib selectively induces apoptosis in some cancer cells. However, the nature of its selectivity remains unknown. Previously, we demonstrated that, in contrast to normal fibroblasts, bortezomib treatment evoked strong effect on apoptosis of breast cancer cells incubated in hypoxic and normoxic conditions. The study presented here provides novel information on the cellular effects of bortezomib in DLD-1 colon cancer cells line. We observe twofold higher percentage of apoptotic cells incubated for 48 h with 25 and 50 nmol/l of bortezomib in hypoxic conditions and four-, fivefold increase in normoxic conditions in comparison to control cells, incubated without bortezomib. It is of interest that bortezomib evokes strong effect on necrosis of DLD-1 colon cancer cell line. We observe the sixfold increase in necrosis of DLD-1 cells incubated with 25 or 50 nmol/l of bortezomib for 48 h in hypoxia and fourfold increase in normoxic conditions in comparison to adequate controls. We suggest that bortezomib may be candidates for further evaluation as chemotherapeutic agents for human colon cancer. 相似文献
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Nadine Grisel Stefan Zoller Marzanna Künzli-Gontarczyk Thomas Lampart Martin Münsterkötter Ivano Brunner Lucien Bovet Jean-Pierre Métraux Christoph Sperisen 《BMC plant biology》2010,10(1):185
Background
Ionic aluminum (mainly Al3+) is rhizotoxic and can be present in acid soils at concentrations high enough to inhibit root growth. Many forest tree species grow naturally in acid soils and often tolerate high concentrations of Al. Previously, we have shown that aspen (Populus tremula) releases citrate and oxalate from roots in response to Al exposure. To obtain further insights into the root responses of aspen to Al, we investigated root gene expression at Al conditions that inhibit root growth. 相似文献14.
Zimecki M Weber-Dabrowska B Łusiak-Szelachowska M Mulczyk M Boratyński J Poźniak G Syper D Górski A 《Cellular & molecular biology letters》2003,8(3):699-711
The aim of this investigation was to reveal the regulatory properties of bacteriophage preparations in a model of mitogen-induced splenocyte proliferation in mice. We showed that sepharose 4B-purified preparations of the Staphylococcus aureus phage A20/R exhibited costimulatory activity in splenocyte proliferation induced by suboptimal (0.25 microg/ml) concentrations of ConA. On the other hand, the purified phage fraction was regulatory with regard to splenocyte proliferation induced by the optimal (2.5 microg/ml) ConA concentration. We also showed that the phage preparation can elicit IL-6 production in splenocyte cultures and enhance ConA-induced production of that cytokine. Furthermore, the phages preferentially induced IL-6 production in adherent splenocytes and increased levels of that cytokine in cultures of peritoneal cells from mice and rats. This phenomenon may explain the costimulatory activity of phages in the model described. 相似文献
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Marzanna Cechowska‐Pasko Rafał Krętowski Edward Bańkowski 《Cell biology international》2011,35(2):141-145
We decided to study the effect of glucose deprivation on collagen metabolism in MCF7 cells. The incorporation of [3H]‐proline into collagenase‐sensitive and hydroxyproline‐containing proteins was used as an index of collagen synthesis, whereas pulse—chase technique was employed to evaluate the degradation of newly synthesized proteins. The MCF7 cells incubated in high glucose medium synthesized detectable amounts of collagenous proteins. Most of them were found in the cell layer. The shortage of glucose resulted in about 30% reduction in collagen synthesis. The pulse—chase experiments demonstrated that proportionally less collagen was degraded in cultures incubated in low‐glucose than in high‐glucose media. 相似文献
17.
Cechowska-Pasko M Pałka J 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2003,134(4):703-711
Insulin-like growth factor-I (IGF-I) is an important stimulator of collagen and glycosaminoglycan (GAG) biosynthesis in tissues. IGF-I activity is modulated by a family of IGF-binding proteins (IGFBPs) with different IGF-I binding affinities. At least IGFBP-1 and IGFBP-2 are known as inhibitors of IGF functions. Some IGFBPs (IGFBP-1, IGFBP-3 and IGFBP-5) may undergo phosphorylation that dramatically increase their affinity for IGF. During fasting of animals there is a significant decrease of the collagen and GAG content of the skin, accompanied by a reduction of plasma IGF-I levels. However, in previous studies we showed that in the skin of fasted rats IGF-I as well as IGFBP-1 and IGFBP-2 expressions were not different, compared to control rat skin, although collagen content was significantly decreased. In the present study we show that fasted rat skin contains similar amounts of IGF-I, IGFBP-3 and IGFBP-1, although extract from fasted rat skin induced inhibition of collagen biosynthesis in cultured fibroblasts, compared to control rat skin extract. Western immunoblot analysis of control and fasted rat skin extracts, using anti-phosphoserine antibodies for immunoprecipitated IGFBP-1 and IGFBP-3, revealed that both proteins are present in phosphorylated form. Although no differences were found in the expression of phosphorylated IGFBP-3 between control and fasted rat skins, that of phosphorylated IGFBP-1 in fasted rat skin extract was higher than in control one. We suggest that there is an increased level of IGFBP-1 phosphoisoform in fasted rat skin, associated with increased affinity for IGF-I. The increase of phosphorylated IGFBP-1 in fasted rat skin tissue may augment IGF-I binding affinity for IGF and decrease its bioavailability for receptor interaction. This mechanism may prevent IGF-I dependent stimulation of fibroblasts to produce extracellular matrix components. The specific expression of IGFBPs and their phosphoisoforms in tissues may play an important role in regulation of IGF-I action during physiologic and pathologic responses. 相似文献
18.
Fasting is accompanied by a decrease in collagen biosynthesis. The mechanism of this phenomenon involves inhibition of prolidase activity, an enzyme that plays a key role in upregulation of collagen metabolism. The mechanism of fasting-induced inhibition of prolidase activity is not known. Phosphoenolpyruvate (PEP) is known as a strong inhibitor of prolidase activity. It exerts this effect by inhibition of the enzyme phosphorylation. Unphosphorylated prolidase is inactive. One may expect that fasting-associated increase in posphoenolpyruvate content in animal tissues may be a factor which inactivates prolidase and makes it inactive in collagen biosynthesis. We measured the levels of phosphoenolpyruvate, pyruvate, and pyruvate kinase in the skin of control and fasted rats and correlated these parameters with prolidase expression, prolidase activity and collagen biosynthesis in this tissue. Significant increase of PEP concentration (about 30%) was found in the skin of fasted rats. In the same time prolidase activity and collagen biosynthesis decreased by about 50% and 30%, respectively, compared to controls. It is known that phosphoenolpyruvate is converted to pyruvate by the action of pyruvate kinase. Since fasting significantly decreases the activity of this enzyme, one may suggest that the accumulation of PEP is caused by a reduced utilisation of this metabolite. As demonstrated by Western immunoblot analysis the decrease in prolidase activity was not accompanied by a decrease in the amount of the enzyme protein. Instead, a decrease in the enzyme phosphorylation was observed. The reduction in phosphorylation seems to be responsible for the decrease in prolidase activity. These data suggest that fasting-evoked accumulation of PEP reduces the activity of prolidase, providing a mechanism for inhibition of collagen biosynthesis in the skin. 相似文献
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Anna Galicka Rafał Krętowski Jolanta Nazaruk Marzanna Cechowska-Pasko 《Molecular and cellular biochemistry》2014,391(1-2):217-224
Thyroid hormone stimulates erythropoietic differentiation. However, severe anemia is sometimes seen in patients with hyperthyroidism, and the mechanisms have not been fully elucidated. Bone marrow is comprised about 2–8 % oxygen, and the characteristics of hematopoietic stem cells have been shown to be influenced under hypoxia. Hypoxia-inducible factor-1 is a critical mediator of cellular responses to hypoxia and an important mediator in signal transduction of thyroid hormone [triiodothyronine (T3)]. The aim of this study was to investigate the effect of T3 on erythropoiesis under hypoxia mimicking physiological conditions in the bone marrow. We maintained human erythroleukemia K562 cells under hypoxic atmosphere (2 % O2) and examined their cellular characteristics. Compared to that under normal atmospheric conditions, cells under hypoxia showed a reduction in the proliferation rate and increase in the hemoglobin content or benzidine-positive rate, indicating promotion of erythroid differentiation. T3 had no effect on hypoxia-induced erythroid differentiation, but significantly inhibited activin A/erythroid differentiation factor-induced erythroid differentiation. Moreover, GATA2 mRNA expression was suppressed in association with erythroid differentiation, while T3 significantly diminished that suppression. These results suggest that T3 has a direct suppressive effect on erythroid differentiation under hypoxic conditions. 相似文献
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Marzanna Chojnacka Anna Skowrońska-Gardas Marzena Morawska-Kaczyńska Anna Zygmuntowicz-Piętka Katarzyna Pędziwiatr Anna Semaniak 《Reports of Practical Oncology and Radiotherapy》2010,15(1):21-24