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Bovine Serum (bovine + serum)
Kinds of Bovine Serum Terms modified by Bovine Serum Selected AbstractsExpression of Notch signalling-related genes in normal and differentiating rat dental pulp cellsAUSTRALIAN ENDODONTIC JOURNAL, Issue 2 2010Hantang Sun dds Abstract Notch signalling is of fundamental importance to various processes during embryonic development and in adults. The possible role of Hey1, an important Notch signalling component, in odontoblast differentiation was evaluated in this study. Primary cultured dental pulp cells, derived from upper incisors of 5-week-old Wistar rats, were placed in ,-modification of Eagle's minimal essential medium supplemented with 10% Fetal Bovine Serum (FBS), and ascorbic acid (AA) and ,-glycerophosphate (,-GP), with or without dexamethasone, and cultured on dishes coated with collagen type IA for 7 days. Conventional and real-time Polymerase Chain Reaction (PCR) was performed to determine the expression of Notch-related genes and dentin sialophosphoprotein as a marker of odontoblast differentiation. Dentin sialophosphoprotein and Hey1 expression was significantly increased and decreased in the presence of AA + ,-GP compared with controls, respectively. These findings suggest that Hey1 may be a negative regulator in odontoblast differentiation. [source] A Study of the Determination of Cu(II) by Anodic Stripping Voltammetry on a Novel Nylon/Carbon Fiber ElectrodeELECTROANALYSIS, Issue 7 2004A. Mylonakis Abstract In this work we report a new electrode material formed by injection-moulding of a conducting polymer consisting of carbon fibers in a Nylon matrix. This material is highly conductive, inexpensive, easy to mould in different shapes and requires minimal pretreatment. The electrode was tested as a mercury-free sensor for the trace determination of Cu(II) by anodic stripping voltammetry (ASV). The deposition and stripping behavior of copper on the conducting material was initially studied by cyclic voltammetry and the chemical and instrumental parameters of the determination were investigated. The electrode has been shown to be suitable for the determination of Cu(II) in the range 8,,g L,1 to 30,mg,L,1 (with deposition times ranging from 30,s to 10,min) with a relative standard deviation of 2.2% (at the 0.5,mg,L,1 level) and a limit of detection of 8,,g L,1 Cu(II) for 10,min of accumulation (at a S/N ratio of 5). The electrode was, finally, applied to the determination of copper in tap-water, pharmaceutical tablets and bovine serum with recoveries of 97.4, 94.9 and 93.4%, respectively [source] Electrophoretically mediated microanalysis for the evaluation of interspecies variation in cholinesterase metabolismELECTROPHORESIS, Issue 14 2010Joana Moura Abstract This study describes an electrophoretically mediated microanalysis method, suitable for the preclinical evaluation of the hydrolysis of ester drugs by the serum of different animals and for further characterization of human,animal correlation. Dog, cat, cow, horse, sheep, rat and human serum were diluted (25%) in the appropriate buffer and replaced the enzyme solution usually used in electrophoretically mediated microanalysis methods for the study of enzyme kinetics. They were then compared in terms of the ability to hydrolyze acetylthiocholine and butyrylthiocholine (0.25,mM) by in-capillary reaction. Human serum afforded the highest conversion rates (52% butyryltiocholine and 34% acetylthiocholine) followed by horse (31 and 35%), dog (26 and 24%), cat (22 and 14%), rat (11 and 15%) and sheep (8 and 8%). Hydrolysis by bovine serum was negligible. The method is fast (under 8,min including rinsing steps), sensitive (under 25,,M substrate could be quantified) and repeatable (RSD,2%), only requiring minute amounts of sample. [source] Acute exposure of human lung cells to 1,3-butadiene diepoxide results in G1 and G2 cell cycle arrestENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 4 2005Michael Schmiederer Abstract 1,3-butadiene (BD) causes genetic damage, including adduct formation, sister chomatid exchange, and point mutations. Previous studies have focused on the types of genetic damage and tumors found after long-term exposure of rodents to butadiene. This study examined the effect of the most active BD metabolite, butadiene diepoxide (BDO2), on cell cycle entry and progression in human lung fibroblasts (LU cells) with a normal diploid karyotype. Serum-arrested (G0) LU cells were exposed to BDO2 for 1 hr and stimulated to divide with medium containing 10% fetal bovine serum. The BDO2 -treated LU cells were evaluated for cell cycle progression, nuclear localization of arrest mediators, mitotic index, and cellular proliferation. The BDO2 -treated cells demonstrated a substantial inhibition of cell proliferation when treated with 100 ,M BDO2 for 1 hr. No appreciable levels of apoptosis or mitotic figures were observed in the BDO2 -treated cells through 96 hr posttreatment. Flow cytometric analysis revealed that the lack of proliferation in BDO2 -treated LU cells was related to G1 arrest in about half of the cells and a delayed progression through S and G2 arrest in nearly all of the remaining cells. Both G1 and G2 arrest were prolonged and only a very small percentage of BDO2 -treated cells were eventually able to replicate. Increased nuclear localization of both p53 and p21cip1 was observed in BDO2 -treated cells, suggesting that the cell cycle arrest was p21cip1 -mediated. These results demonstrate that BDO2 induces cell cycle perturbation and arrest even with short-term exposure that does not produce other pathologic cellular effects. Environ. Mol. Mutagen., 2005. © 2005 Wiley-Liss, Inc. [source] Hydrolysis of acetylthiocoline, o -nitroacetanilide and o- nitrotrifluoroacetanilide by fetal bovine serum acetylcholinesteraseFEBS JOURNAL, Issue 7 2009Marķa F. Montenegro Besides esterase activity, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) hydrolyze o -nitroacetanilides through aryl acylamidase activity. We have reported that BuChE tetramers and monomers of human blood plasma differ in o -nitroacetanilide (ONA) hydrolysis. The homology in quaternary structure and folding of subunits in the prevalent BuChE species () of human plasma and AChE forms of fetal bovine serum prompted us to study the esterase and amidase activities of fetal bovine serum AChE. The kcat/Km values for acetylthiocholine (ATCh), ONA and its trifluoro derivative N -(2-nitrophenyl)-trifluoroacetamide (F-ONA) were 398 × 106 m,1·min,1, 0.8 × 106 m,1·min,1, and 17.5 × 106 m,1·min,1, respectively. The lack of inhibition of amidase activity at high F-ONA concentrations makes it unlikely that there is a role for the peripheral anionic site (PAS) in F-ONA degradation, but the inhibition of ATCh, ONA and F-ONA hydrolysis by the PAS ligand fasciculin-2 points to the transit of o -nitroacetalinides near the PAS on their way to the active site. Sedimentation analysis confirmed substrate hydrolysis by tetrameric 10.9S AChE. As compared with esterase activity, amidase activity was less sensitive to guanidine hydrochloride. This reagent led to the formation of 9.3S tetramers with partially unfolded subunits. Their capacity to hydrolyze ATCh and F-ONA revealed that, despite the conformational change, the active site architecture and functionality of AChE were partially retained. [source] Expression and functional characterization of P2Y1 and P2Y12 nucleotide receptors in long-term serum-deprived glioma C6 cellsFEBS JOURNAL, Issue 8 2007Patryk Krzemi We characterized the expression and functional properties of the ADP-sensitive P2Y1 and P2Y12 nucleotide receptors in glioma C6 cells cultured in medium devoid of serum for up to 96 h. During this long-term serum starvation, cell morphology changed from fibroblast-like flat to round, the adhesion pattern changed, cell-cycle arrest was induced, extracellular signal-regulated kinase (ERK1/2) phosphorylation was reduced, Akt phosphorylation was enhanced, and expression of the P2Y12 receptor relative to P2Y1 was increased. These processes did not reflect differentiation into astrocytes or oligodendrocytes, as expression of glial fibrillary acidic protein and NG2 proteoglycan (standard markers of glial cell differentiation) was not increased during the serum deprivation. Transfer of the cells into fresh medium containing 10% fetal bovine serum reversed the changes. This demonstrates that serum starvation caused only temporary growth arrest of the glioma C6 cells, which were ready for rapid division as soon as the environment became more favorable. In cells starved for 72 and 96 h, expression of the P2Y1 receptor was low, and the P2Y12 receptor was the major player, responsible for ADP-evoked signal transduction. The P2Y12 receptor activated ERK1/2 kinase phosphorylation (a known cell proliferation regulator) and stimulated Akt activity. These effects were reduced by AR-C69931MX, a specific antagonist of the P2Y12 receptor. On the other hand, Akt phosphorylation increased in parallel with the low expression of the P2Y1 receptor, indicating the inhibitory role of P2Y1 in Akt pathway signaling. The shift in nucleotide receptor expression from P2Y1 to P2Y12 would appear to be a new and important self-regulating mechanism that promotes cell growth rather than differentiation and is a defense mechanism against effects of serum deprivation. [source] Lithium-mediated suppression of morphogenesis and growth in Candida albicansFEMS YEAST RESEARCH, Issue 4 2008Layla F. Martins Abstract Hyphal development in Candida albicans contributes to virulence, and inhibition of filamentation is a target for the development of antifungal agents. Lithium is known to impair Saccharomyces cerevisiae growth in galactose-containing media by inhibition of phosphoglucomutase, which is essential for galactose metabolism. Lithium-mediated phosphoglucomutase inhibition is reverted by Mg2+. In this study we have assessed the effect of lithium upon C. albicans and found that growth is inhibited preferentially in galactose-containing media. No accumulation of glucose-1-phosphate or galactose-1-phosphate was detected when yeasts were grown in the presence of galactose and 15 mM LiCl, though we observed that in vitro lithium-mediated phosphoglucomutase inhibition takes place with an IC50 of 2 mM. Furthermore, growth inhibition by lithium was not reverted by Mg2+. These results show that lithium-mediated inhibition of growth in a galactose-containing medium is not due to inhibition of galactose conversion to glucose-6-phosphate but is probably due to inhibition of a signaling pathway. Deletion of the Ser-Thr protein phosphatase SIT4 and treatment with rapamycin have been shown to inhibit filamentous differentiation. We observed that C. albicans filamentation was inhibited by lithium in solid medium containing either galactose as the sole carbon source or 10% fetal bovine serum. These results suggest that suppression of hyphal outgrowth by lithium could be related to inhibition of the target of rapamycin (TOR) pathway. [source] Optimization of the culturing conditions of human umbilical cord blood-derived endothelial colony-forming cells under xeno-free conditions applying a transcriptomic approachGENES TO CELLS, Issue 7 2010Steffen M. Zeisberger Establishment of fetal bovine serum (FBS)-free cell culture conditions is essential for transplantation therapies. Blood-derived endothelial colony-forming cells (ECFCs) are potential candidates for regenerative medicine applications. ECFCs were isolated from term umbilical cord blood units and characterized by flow cytometry, capillary formation and responsiveness to cytokines. ECFCs were expanded under standard, FBS-containing endothelial medium, or transferred to chemically defined endothelial media without FBS. Microarray expression profiling was applied to compare the transcriptome profiles in FBS-containing versus FBS-free culture. ECFC outgrowth in standard medium was successful in 92% of cord blood units. The karyotype of expanded ECFCs remained normal. Without FBS, ECFC initiation and expansion failed. Modest proliferation, changes in cell morphology and organization and cell death have been observed after passaging. Gene ontology analysis revealed a broad down-regulation of genes involved in cell cycle progression and up-regulation of genes involved in stress response and apoptosis. Interestingly, genes participating in lipid biosynthesis were markedly up-regulated. Detection of several endothelial cell-specific marker genes showed the maintenance of the endothelial cell characteristics during serum-free culture. Although ECFCs maintain their endothelial characteristics during serum-free culturing, they could not be expanded. Additional supply of FBS-free media with lipid concentrates might increase the ECFC survival. [source] Cytotoxicity of MTA and Portland cement on human ECV 304 endothelial cellsINTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2005G. De Deus Abstract Aim, To evaluate the cytotoxic effects of two brands of mineral trioxide aggregate (MTA) (Pro-Root MTA® and MTA Angelus®) and Portland cement (PC) on the human ECV 304 endothelial cell line. Methodology, Endothelial ECV 304 cells were incubated at 37 °C in an atmosphere of 95% air, 5% carbon dioxide and 100% humidity for 7 days and grown in F12 medium supplemented with 10% fetal bovine serum with 50 ,g mL,1 of gentamicin sulphate. Effects of the materials on mitochondrial functions were measured by a colorimetric assay. At each experimental time interval (24, 48 and 72 h), a dimethyl-thiazol-diphenyl tetrazolium bromid assay was conducted to measure cell viability. All assays were repeated three times to ensure reproducibility. Results were expressed as average absorbance (A570\,nm) ± SD and the data were analysed statistically by one-way analysis of variance and the Bonferroni post-test. A P -value <0.05 was considered statistically significant. Results, No statistically significant difference was shown between any of the experimental materials (P > 0.05). Conclusions, The two brands of MTA analysed, as well as the PC, initially showed a similar elevated cytotoxic effect that decreased gradually with time allowing the cell culture to become reestablished. [source] Lead-dependent effects on arachidonic acid accumulation and the proliferation of vascular smooth muscleJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 5 2002Robert V. Dorman Abstract Lead (Pb2+) has been implicated in the development of hypertension and atherosclerosis. The proliferation of vascular smooth muscle cells (VSMC) is a central feature of both conditions and there is evidence that Pb2+ potentiates serum-dependent cell growth. The aim of this work was to examine the role of phospholipase A2 in mitogen-dependent VSMC proliferation and determine if Pb2+ interacts with this system in order to potentiate mitotic events. It was observed that cell proliferation induced by angiotensin II, or fetal bovine serum, required the activation of a Ca2+ -dependent cytosolic phospholipase A2 and the subsequent release of unesterified arachidonic acid. This path was affected by Pb2+ as the metal increased the amount of arachidonic acid accumulation induced by either mitogen. In addition, Pb2+ potentiated mitogen-induced DNA synthesis when present at lower doses (0.02 or 0.2 mg%), but had no effect on DNA synthesis, or cell numbers, in unstimulated cells. However, a high dose (2 mg%) of Pb2+ attenuated the DNA synthesis stimulated by angiotensin II, or serum, but induced the accumulation of unesterified arachidonic acid in unstimulated cells. A biphasic effect of Pb2+ on cell numbers and viability was also observed as 0.02 or 0.2 mg% Pb2+ did not affect cell numbers or trypan blue exclusion in unstimulated cells, while 2 mg% Pb2+ reduced cell numbers and viability. It appeared, therefore, that the lower concentrations of Pb2+ increased arachidonic acid release and DNA synthesis only in stimulated VSMC, perhaps due to further activation of a Ca2+ -dependent processes. In contrast, the high dose of Pb2+ reduced DNA synthesis in stimulated cells and reduced cell numbers and viability in unstimulated cells, which may relate to the noted increase in unesterified arachidonic acid. © 2002 Wiley Periodicals, Inc. J Biochem Mol Toxicol 16:245,253, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10045 [source] Role of D1 and E Cyclins in Cell Cycle Progression of Human Fibroblasts Adhering to Cementum Attachment Protein,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2001Takayoshi Yokokoji Abstract Cementum attachment protein (CAP) is a collagenous protein present in the matrix of tooth cementum that mediates preferential attachment of some mesenchymal cell types, and CAP binding capacity is related to mineralizing tissue-forming capacity in culture. We have examined if adhesion to surfaces containing CAP as the only attachment protein permits human fibroblasts to escape G1 arrest and synthesize DNA, and if adhesion to CAP modulates the levels of cyclins D1 and E. Human gingival fibroblasts (HGFs) were serum-starved, trypsinized, and added to plates coated with CAP or bovine serum albumin (BSA). Cells were then exposed to either 10% fetal bovine serum (FBS) or to cementum-derived growth factor (CGF), an insulin-like growth factor I (IGF-I)-like molecule sequestered in tooth cementum, plus epidermal growth factor (EGF). DNA synthesis was measured as [3H]thymidine uptake, and cyclin D1 and E levels were determined by Western analysis. Cyclin E-dependent kinase (Cdk) activity was assessed in terms of H1 kinase activity in immunoprecipitates of cyclin E. Cells adhering to CAP synthesized DNA, whereas on BSA they remained unattached and did not synthesize DNA. Protein levels of cyclin D1 were higher in cells adhering to CAP in the absence and presence of growth factors. Cyclin E levels were not affected by adhesion alone, but they increased in the presence of growth factors. Cyclin E-associated kinase activity was higher in cells adherent on CAP, and it increased further in the presence of growth factors. Our results indicate that adhesion to CAP increases cyclin D1 levels and cyclin E-associated Cdk activity, and that these increases contribute to cell cycle progression. We previously observed that the signaling reactions induced during adhesion are characteristic of the CAP; together these observations indicate that specific matrix components present in the local environment can contribute to recruitment and differentiation of specific cell types for normal homeostasis and wound healing. [source] Human islet-derived precursor cells can cycle between epithelial clusters and mesenchymal phenotypesJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 8b 2009Behrous Davani Abstract We showed previously that undifferentiated, proliferating human islet-derived precursor cells (hIPCs) are a type of mesenchymal stem/stromal cell (MSC) that can be induced by serum deprivation to form clusters and ultimately differentiate in vitro to endocrine cells. We also demonstrated that partially differentiated hIPC clusters, when implanted under the kidney capsules of mice, continued to differentiate in vivo into hormone-producing cells. However, we noted that not all hIPC preparations yielded insulin-secreting cells in vivo and that in some animals no hormone-expressing cells were found. This suggested that the implanted cells were not always irreversibly committed to further differentiation and may even de-differentiate to a mesenchymal phenotype. In this study, we show that human cells with a mesenchymal phenotype are indeed found in the grafts of mice implanted with hIPCs in epithelial cell clusters (ECCs), which are obtained after 4-day in vitro culture of hIPCs in serum-free medium (SFM); mesenchymal cells were predominant in some grafts. We could mimic the transition of ECCs to de-differentiated mesenchymal cells in vitro by exposure to foetal bovine serum (FBS) or mouse serums, and to a significantly lesser extent to human serum. In a complementary series of experiments, we show that mouse serum and FBS are more effective stimulants of mesenchymal hIPC migration than is human serum. We found that proliferation was not needed for the transition from ECCs to de-differentiated cells because mitomycin-treated hIPCs that could not proliferate underwent a similar transition. Lastly, we show that cells exhibiting a mesenchymal phenotype can be found in grafts of adult human islets in mice. We conclude that epithelial-to-mesenchymal transition (EMT) of cells in hIPC ECCs can occur following implantation in mice. This potential for EMT of human islets or differentiated precursor cells must be considered in strategies for cell replacement therapy for diabetes. [source] Prognostic value of serum angiogenic activity in colorectal cancer patientsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2007Francisco-Jesus Gonzalez Abstract Angiogenesis, resulting from an imbalance between angiogenic activator factors and inhibitors, is required for tumour growth and metastasis. The determination of the circulating concentration of all angiogenic factors (activators and inhibitors) is not feasible at present. We have evaluated diagnostic and prognostic values of the measurement of serum angiogenic activity in colorectal carcinoma (CRC) patients. Serum proliferative activity (PA) on human umbilical vein endothelial cells (HUVEC) in vitro, and serum vascular endothelial growth factor (VEGF) levels were determined by ELISA in 53 patients with primary CRC, 16 subjects with non-neoplastic gastrointestinal disease (SC) and 34 healthy individuals. Data were compared with clinical outcome of the patients. Although serum from CRC patients significantly increased the PA of HUVEC, compared to culture control (HUVEC in medium + 10% foetal bovine serum (FBS); P < 0.001); our results indicate that serum PA in CRC patients was similar to that of SC or healthy individuals. There was no correlation between serum PA and circulating VEGF concentrations. Surgery produced a decrease of PA at 8 hrs after tumour resection in CRC patients compared to pre-surgery values (186 ± 47 versus 213 ± 41, P < 0.001). However, an increase in serum VEGF values was observed after surgery (280 [176,450] versus 251 [160,357] pg/ml, P = 0.004). Patients with lower PA values after surgery showed a worse outcome that those with higher PA values. Therefore, this study does not support a diagnostic value for serum angiogenic activity measured by proliferative activity on HUVEC but suggests it could have a prognostic value in CRC patients. [source] Corticosterone induces steroidogenic lesion in cultured adult rat leydig cells by reducing the expression of star protein and steroidogenic enzymesJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 5 2008Srinivasan Rengarajan Abstract The present study was designed to investigate the dose-dependent direct effect of corticosterone on adult rat Leydig cell steroidogenesis in vitro. Leydig cells were isolated from the testis of normal adult male albino rats, purified on discontinuous Percoll gradient and plated in culture plates/flasks overnight at 34°C in a CO2 incubator under 95% air and 5% CO2 using DME/F12 medium containing 1% fetal bovine serum. After the attachment of cells, serum-containing medium was removed and cells were exposed to different doses (0, 50, 100, 200, 400, and 800 nM) of corticosterone using serum-free fresh medium for 24 h at 34°C. At the end of exposure period, cells were utilized for assessment of the activities and mRNA expression of steroidogenic enzymes (cytochrome P450 side chain cleavage enzyme, 3,-hydroxysteroid dehydrogenase, 17,-hydroxysteroid dehydrogenase, and cytochrome P450 aromatase) and steroidogenic acute regulatory protein gene expression. Testosterone and estradiol production were also quantified. Activities of cytochrome P450 side chain cleavage enzyme, 3,- and 17,-hydroxysteroid dehydrogenases were declined significantly in a dose-dependent manner after corticosterone exposure, while their mRNA expression were significantly reduced at higher doses of corticosterone exposure. The activity and mRNA expression of cytochrome P450 aromatase registered a significant increase at 100 nM dose of corticosterone whereas at 200,800 nM doses both the activity as well as the mRNA levels was significantly reduced below the basal level. StAR protein gene expression was significantly inhibited by higher doses of corticosterone employed. At all doses employed, corticosterone significantly reduced the production of testosterone by Leydig cells, while estradiol level registered a significant increase at 50 and 100 nM doses but at higher doses, it registered a significant decrease when compared to basal level. It is concluded from the present in vitro study that the molecular mechanism by which corticosterone reduces the production of Leydig cell testosterone is by reducing the activities and mRNA expression of steroidogenic enzymes and steroidogenic acute regulatory protein. J. Cell. Biochem. 103: 1472,1487, 2008. © 2007 Wiley-Liss, Inc. [source] Overexpression of RGPR-p117 enhances regucalcin gene promoter activity in cloned normal rat kidney proximal tubular epithelial cells: Involvement of TTGGC motifJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2006Natsumi Sawada Abstract A novel protein RGPR-p117 was discovered as regucalcin gene promoter region-related protein that binds to the TTGGC motif using a yeast one-hybrid system. RGPR-p117 is localized in the nucleus of kidney cells, and overexpression of RGPR-p117 can modulate regucalcin protein and its mRNA expression in the cloned normal rat kidney proximal tubular epithelial NRK52E cells. This study was undertaken to determine whether overexpression of RGPR-p117 enhances the regucalcin promoter activity using the ,710/+18 LUC construct (wild-type) or ,710/+18 LUC construct (mutant) with deletion of ,523/,435 including TTGGC motif. NRK52E cells (wild-type) or stable HA-RGPR-p117/phCMV2-transfected cells (transfectant) were cultured in Dulbecco's minimum essential medium (DMEM) containing 5% bovine serum (BS). Wild-type cells or transfectants were transfected with the ,710/+18 LUC construct vector or the ,710/+18 LUC construct with deletion of ,523/,435. Wild-type cells or transfectants with subconfluency were cultured for 48 h in a DMEM medium containing either vehicle, BS (5%), or parathyroid hormone (1,34) (PTH; 10,7 M). Luciferase activity in wild-type cells was significantly increased with culture of BS or PTH. This increase was significantly blocked in the presence of various protein kinase inhibitors (staurosporine and PD 98059). Luciferase activity in transfectants was significantly increased as compared with that of wild-type cells in the absence of BS or PTH. The increase in luciferase activity in transfectants was completely decreased in mutant with deletion of ,523/,435 sequence of regucalcin promoter. This was also seen using the ,710/+18 LUC construct with deletion of ,523/,503 sequence containing TTGGC motif. The increase in luciferase activity in transfectants was not significantly enhanced with culture of BS (5%), PTH (10,7 M), Bay K 8644 (10,6 M), phorbol 12-myristate 13-acetate (PMA; 10,6 M), or N6, 2,-dibutyryl cyclic adenosine 3,, 5,-monophosphate (DcAMP; 10,4 M). The increase in luciferase activity in transfectants was completely inhibited with culture of dibucaine (10,6 M), staurosporine (10,9 M), PD 98059 (10,8 M), wortmannin (10,8 M), genistein (10,6 M), vanadate (10,6 M), or okadaic acid (10,6 M) which are inhibitors of various kinases and protein phosphatases. This study demonstrates that RGPR-p117 can enhance the regucalcin promoter activity which is related to the NF-1 consensus sequences including TTGGC motif, and that its enhancing effect is partly mediated through phosphorylation and dephosphorylation in NRK52E cells. J. Cell. Biochem. 99: 589,597, 2006. © 2006 Wiley-Liss, Inc. [source] ,-cryptoxanthin stimulates cell differentiation and mineralization in osteoblastic MC3T3-E1 cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2005Satoshi Uchiyama Abstract The effect of ,-cryptoxanthin, a kind of carotenoid, on cell differentiation and mineralization in osteoblastic MC3T3-E1 cells was investigated. Cells were cultured for 72 h in a minimum essential medium containing 10% fetal bovine serum (FBS), and the cells with subconfluency were changed to a medium containing either vehicle or ,-cryptoxanthin (10,8 to 10,6 M) without FBS. Cells were cultured for 3 to 21 days. Gene expression in osteoblastic cells was determined using reverse transcription-polymerase chain reaction (RT-PCR). Culture with ,-cryptoxanthin (10,7 or 10,6 M) for 3 days caused a significant increase in Runx2 type 1, Runx2 type 2, ,1 (I) collagen, and alkaline phosphatase mRNA levels in osteoblastic cells. These increases were completely blocked in the presence of cycloheximide, an inhibitor of protein synthesis, or 5,6-dichloro-1-,- D -ribofuranosylbenzimidazole (DRB), an inhibitor of transcriptional activity. Meanwhile, vitamin A (10,6 M) did not have a significant effect on Runx2 type 1 mRNA expression in the cells. The effect of ,-cryptoxanthin (10,6 M) in stimulating Runx2 type 1 and ,1 (I) collagen mRNA levels, protein content, and alkaline phosphatase activity in the cells was also seen in the presence of vitamin A (10,6 M), suggesting that the mode of ,-cryptoxanthin action differs from that of vitamin A. Prolonged culture with ,-cryptoxanthin (10,6 M) for 3 to 21 days caused a significant increase in cell number, deoxyribonucleic acid (DNA) content, protein content, and alkaline phosphatase activity in osteoblastic cells, suggesting that ,-cryptoxanthin stimulates cell proliferation and differentiation. Moreover, culture with ,-cryptoxanthin (10,7 or 10,6 M) for 5 to 21 days caused a remarkable increase in mineralization. This study demonstrates that ,-cryptoxanthin has a stimulatory effect on cell differentiation and mineralization due to enhancing gene expression of proteins, which involve in bone formation in osteoblastic MC3T3-E1 cells. © 2005 Wiley-Liss, Inc. [source] Suppressive role of endogenous regucalcin in the enhancement of protein kinase activity with proliferation of cloned rat hepatoma cells (H4-II-E)JOURNAL OF CELLULAR BIOCHEMISTRY, Issue S36 2001Shyuichiroh Inagaki Abstract The role of endogenous regucalcin, which is a regulatory protein in calcium signaling, in the regulation of protein kinase activity in the proliferation of the cloned rat hepatoma cells (H4-II-E) was investigated. Hepatoma cells were cultured for 6,72,h in the presence of fetal bovine serum (FBS; 1 or 10%). The number of cells and protein kinase activity in the 5500,g supernatant of cell homogenate was significantly increased 24 and 48,h after the culture with FBS (1 or 10%); the culture with 10% FBS was potent effect as compared with that of 1% FBS. FBS (10%)-increased protein kinase activity preceded a significant elevation of cell number of 6,h after culture. Serum stimulation-induced increase in protein kinase activity was significantly decreased in the presence of trifluoperazine (50,,M), staurosporine (10,6,M) or genistein (10,5,M) in the enzyme reaction mixture. The presence of anti-regucalcin monoclonal antibody (40 or 80,ng/ml) in the reaction mixture caused a significant increase in protein kinase activity in the cells cultured with FBS (1 or 10%). This increase was completely blocked by addition of regucalcin (10,6,M), which can reveal an inhibitory effect on protein kinase activity. Moreover, the effect of antibody in increasing protein kinase activity was significantly inhibited in the presence of trifluoperazine, staurosporine, or genistein, indicating that endogenous regucalcin has an inhibitory effect on Ca2+/calmodulin-dependent protein kinase, protein kinase C, and protein tyrosine kinase. The present study suggests that endogenous regucalcin plays a suppressive role in the enhancement of various protein kinase activities associated with a proliferation of the cloned rat hepatoma cells (H4-II-E). J. Cell. Biochem. 36: 12-18, 2001. © 2001 Wiley-Liss. Inc. [source] Candida dubliniensis screening using the germ tube test in clinical yeast isolates and prevalence of C. dubliniensis in KoreaJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 3 2010Tae-Hyoung Kim Abstract The aim of this study was to screen for C. dubliniensis using the germ tube test with human pooled serum (HPS) in clinical isolates and investigate the prevalence of C. dubliniensis in Korea. Among 1,854 yeast strains isolated, 1,404 strains of C. albicans (on the basis of positive results of the germ tube test) and 192 germ tube-negative yeast strains were examined. All 1,596 clinical isolates were examined using the germ tube test with HPS, the differential temperature, and NaCl tolerance test. Only 81 isolates that did not grow at 45°C nor on Sabouraud 6.5% NaCl broth were selected and tested using the VITEK 2 ID-YSTsystem and the multiplex-PCR assay for the study. The two strains, C. dubliniensis ATCC MYA-646 and KCTC 17427 failed to produce germ tubes in HPS but produced them in fresh rabbit serum (FRS) and fetal bovine serum (FBS). No C. dubliniensis was found in this study population. The results of this study suggest that the germ tube test with HPS in combination with FRS or FBS can be used for discriminating between C. albicans and C. dubliniensis strains and that the prevalence of C. dubliniensis appears to be extremely low in Korea. J. Clin. Lab. Anal. 24:145,148, 2010. © 2010 Wiley-Liss, Inc. [source] Characterization of apoptosis induced by grouper iridovirus in two newly established cell lines from barramundi, Lates calcarifer (Bloch)JOURNAL OF FISH DISEASES, Issue 11 2008Y-S Lai Abstract Two new cell lines have been established from the muscle and swim bladder tissues of barramundi, Lates calcarifer, and designated as BM (barramundi muscle) and BSB (barramundi swimbladder), respectively. The cells multiplied well at 28 °C in Leibovitz's L-15 medium supplemented with 10% foetal bovine serum, and have been continuously subcultured more than 100 times to date. Morphologically, BM cells were mostly fibroblastic, whereas BSB were mostly epithelial. Both cell lines were susceptible to grouper iridovirus (GIV) and displayed characteristics of apoptosis after viral infection. The induction of apoptosis was further assayed in GIV-infected BM and BSB cells by various methods. The inhibition of cell growth by GIV was demonstrated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Morphological observations revealed typical apoptotic features in the infected cells, including cell shrinkage and rounding, chromosome condensation and formation of apoptotic body-like vesicles. Chromosome fragmentation was detected by DNA laddering and TUNEL assays. Finally, the appearance of phosphotidylserine on the outer leaflet of apoptotic cell membranes was confirmed by annexin V staining. This is the first report of apoptosis induced by GIV in fish cells. [source] Establishment and characterization of two new cell lines derived from flounder, Paralichthys olivaceus (Temminck & Schlegel)JOURNAL OF FISH DISEASES, Issue 11-12 2003M S Kang Abstract Two new cell cultures from flounder, Paralichthys olivaceus (Temminck & Schlegel), flounder fin (FFN) cells from fin tissue and flounder spleen (FSP) cells from spleen tissue, were established and characterized. The cells multiplied well in Eagle's minimum essential medium, supplemented with 10% foetal bovine serum, and have been subcultured more than 100 times, becoming continuous cell lines. Modal diploid chromosome number of FFN and FSP cells was 64 and 62, respectively. Polymerase chain reaction products were obtained from FFN and FSP cells with primer sets of microsatellite markers of flounder. Optimal growth temperature was 20 °C and consisted of epithelioid cells. FFN and FSP cells showed cytopathic effects after inoculation of infectious pancreatic necrosis virus, marine birnavirus, chum salmon virus, infectious haematopoietic necrosis virus, spring viraemia of carp virus and hirame rhabdovirus. Thus these new cell lines may be useful for studying a wide range of fish viruses. [source] Two iridovirus-susceptible cell lines established from kidney and liver of grouper, Epinephelus awoara (Temminck & Schlegel), and partial characterization of grouper iridovirusJOURNAL OF FISH DISEASES, Issue 6 2000Y-S Lai Two iridovirus-susceptible cell lines were established and characterized from grouper Epinephelus awoara kidney and liver tissues. These cell lines have been designated GK and GL, respectively. The cells multiplied well in Leibovitz's L-15 medium, supplemented with 10% foetal bovine serum, at temperatures between 20 and 32 °C, and have been subcultured more than 120 times, becoming continuous cell lines. The cell lines consist of a heterogeneous mixture of fibroblastic and epithelial cells. The viability of cells, stored frozen in liquid nitrogen (,196 °C), was 95% after 1 year. Chromosome morphologies of GK and GL cells were homogeneous. Both cell lines were susceptible to grouper iridovirus, and yielded high titres of up to 108 TCID50 mL,1. In addition, both cell lines effectively replicated the virus, which could be purified to homogeneity by cesium chloride gradient centrifugation. Electron microscopy studies showed that purified virus particles were 170±10 nm in diameter, and were hexagonal in shape. Virus-infected cells showed an abundance of virus particles inside the cytoplasm. These results show that the GK and GL cell lines effectively replicate grouper iridovirus, and can be used as a tool for studying fish iridoviruses. [source] A validated method for the determination of nicotine, cotinine, trans -3,-hydroxycotinine, and norcotinine in human plasma using solid-phase extraction and liquid chromatography-atmospheric pressure chemical ionization-mass spectrometryJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 6 2006Insook Kim Abstract A liquid chromatographic-mass spectrometric method for the simultaneous determination of nicotine, cotinine, trans -3,-hydroxycotinine, and norcotinine in human plasma was developed and validated. Analytes and deuterated internal standards were extracted from human plasma using solid-phase extraction and analyzed by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometric detection with selected ion monitoring (SIM). Limits of detection and quantification were 1.0 and 2.5 ng/ml, respectively, for all analytes. Linearity ranged from 2.5 to 500 ng/ml of human plasma using a weighting factor of 1/x; correlation coefficients for the calibration curves were > 0.99. Intra- and inter-assay precision and accuracy were < 15.0%. Recoveries were 108.2,110.8% nicotine, 95.8,108.7% cotinine, 90.5,99.5% trans -3,-hydroxycotinine, and 99.5,109.5% norcotinine. The method was also partially validated in bovine serum, owing to the difficulty of obtaining nicotine-free human plasma for the preparation of calibrators and quality control (QC) samples. This method proved to be robust and accurate for the quantification of nicotine, cotinine, trans -3,-hydroxycotinine, and norcotinine in human plasma collected in clinical studies of acute nicotine effects on brain activity and on the development of neonates of maternal smokers. Copyright © 2006 John Wiley & Sons, Ltd. [source] Selective enhancement of the activity of C-terminally truncated, but not intact, acetylcholinesteraseJOURNAL OF NEUROCHEMISTRY, Issue 1 2008Martina Zimmermann Abstract Acetylcholinesterase (AChE) is one of the fastest enzymes approaching the catalytic limit of enzyme activity. The enzyme is involved in the terminal breakdown of the neurotransmitter acetylcholine, but non-enzymatic roles have also been described for the entire AChE molecule and its isolated C-terminal sequences. These non-cholinergic functions have been attributed to both the developmental and degenerative situation: the major form of AChE present in these conditions is monomeric. Moreover, AChE has been shown to lose its typical characteristic of substrate inhibition in both development and degeneration. This study characterizes a form of AChE truncated after amino acid 548 (T548-AChE), whose truncation site is homologue to that of a physiological form of T-AChE detected in fetal bovine serum that has lost its C-terminal moiety supposedly due to proteolytic cleavage. Peptide sequences covered by this C-terminal sequence have been shown to be crucially involved in both developmental and degenerative mechanisms in vitro. Numerous studies have addressed the structure,function relationship of the AChE C-terminus with T548-AChE representing one of the most frequently studied forms of truncated AChE. In this study, we provide new insight into the understanding of the functional characteristics that T548-AChE acquires in solution: T548-AChE is incubated with agents of varying net charge and molecular weight. Together with kinetic studies and an analysis of different molecular forms and aggregation states of T548-AChE, we show that the enzymatic activity of T548-AChE, an enzyme verging at its catalytic limit is, nonetheless, apparently enhanced by up to 800%. We demonstrate, first, how the activity of T548-AChE can be enhanced through agents that contain highly positive charged moieties. Moreover, the un-competitive mechanism of activity enhancement most likely involves the peripheral anionic site of AChE that is reflected in delayed substrate inhibition being observed for activity enhanced T548-AChE. The data provides evidence towards a mechanistic and functional link between the form of AChE unique to both development and degeneration and a C-terminal peptide of T-AChE acting under those conditions. [source] The entrapment of corrosion products from CoCr implant alloys in the deposits of calcium phosphate: A comparison of serum, synovial fluid, albumin, EDTA, and waterJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2006A. C. Lewis Abstract Physical wear of orthopedic implants is inevitable. CoCr alloy samples, typically used in joint reconstruction, corrode rapidly after removal of the protective oxide layer. The behavior of CoCr pellets immersed in human serum, foetal bovine serum (FBS), synovial fluid, albumin in phosphate-buffered saline (PBS), EDTA in PBS, and water were studied using X-ray Photoelectron Spectroscopy (XPS) and Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS). The difference in the corrosive nature of human serum, water, albumin in PBS and synovial fluid after 5 days of immersion was highlighted by the oxide layer, which was respectively 15, 3.5, 1.5, and 1.5 nm thick. The thickness of an additional calcium phosphate deposit from human serum and synovial fluid was 40 and 2 nm, respectively. Co and Cr ions migrated from the bulk metal surface and were trapped in this deposit by the phosphate anion. This may account for the composition of wear debris from CoCr orthopedic implants, which is known to consist predominantly of hydroxy-phosphate compounds. Known components of synovial fluid including proteoglycans, pyrophosphates, phospholipids, lubricin, and superficial zone protein (SZP), have been identified as possible causes for the lack of significant calcium phosphate deposition in this environment. Circulation of these compounds around the whole implant may inhibit calcium phosphate deposition. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:1587,1596, 2006 [source] Effect of transforming growth factor-beta1 on expression of the connective tissue growth factor (CCN2/CTGF) gene in normal human gingival fibroblasts and periodontal ligament cellsJOURNAL OF PERIODONTAL RESEARCH, Issue 2 2009H. Takeuchi Background and Objective:, Connective tissue growth factor (CCN2/CTGF) plays an important role in wound healing and regulation of the extracellular matrix in periodontal tissue. However, the functional relationship between altered transforming growth factor-beta1 levels and CCN2/CTGF has not been extensively investigated in human gingival fibroblasts and periodontal ligament cells. This study investigated the effects of transforming growth factor-beta1 on the expression of the CCN2/CTGF gene in human gingival fibroblasts and periodontal ligament cells in vitro. Material and Methods:, Cells were isolated from normal periodontal tissues and cultured in Dulbecco's modified Eagle's minimal essential medium/F12 containing 10% fetal bovine serum. Subconfluent cells were maintained under serum deprivation for 24 h then treated with Dulbecco's modified Eagle's minimal essential medium/F12 containing 0.5% fetal bovine serum (control) and 0.1, 1, 5 or 10 ng/mL of transforming growth factor-beta1 for 24, 48 or 72 h. The effects of transforming growth factor-beta1 on CCN2/CTGF mRNA expression were measured by reverse transcription,polymerase chain reaction. CCN2/CTGF protein was quantitatively analyzed using enzyme-liked immunosorbent assay. Subcellular distribution of CCN2/CTGF protein in both human gingival fibroblasts and periodontal ligament cells was observed using immunofluorescence microscopy. Results:, In both human gingival fibroblasts and periodontal ligament cells, the expression of CCN2/CTGF mRNA and CCN2/CTGF protein was significantly increased, in a dose- and time-dependent manner, in the presence of transforming growth factor-beta1. Moreover, immunofluorescence analysis indicated that immunoreactivity to CCN2/CTGF showed a granular pattern of protein localization. Conclusion:, The expression of CCN2/CTGF mRNA and protein was induced by transforming growth factor-beta1 in human gingival fibroblasts and periodontal ligament cells. These results suggest that CCN2/CTGF plays an important role in wound healing and in the regeneration of periodontal tissue. [source] Comparison of suppressive potency between prednisolone and prednisolone sodium succinate against mitogen-induced blastogenesis of human peripheral blood mononuclear cells in-vitroJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 5 2001Kentaro Sugiyama Clinically, both prednisolone and prednisolone sodium succinate are widely used as immunosuppressive agents for the treatment of various allergic disorders. However, whether prednisolone sodium succinate itself has immunosuppressive or anti-inflammatory effects is unclear, and prednisolone sodium succinate may exhibit its efficacy only after hydrolytic conversion to prednisolone in-vivo. If this is the case, the impairment of prednisolone sodium succinate conversion to prednisolone in some clinical conditions may attenuate the efficacy of prednisolone sodium succinate. We therefore compared the pharmacological efficacy of prednisolone with that of prednisolone sodium succinate in-vitro using human peripheral blood mononuclear cells (PBMCs). PBMCs were obtained from 5 healthy subjects and 1 patient with pneumonia. The cells were incubated in the presence of concanavalin A and the cell growth was estimated by 3-(4,5-dimethyl thiazo-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Both prednisolone and prednisolone sodium succinate dose-dependently suppressed PBMC blastogenesis. Mean (s.d.) prednisolone and prednisolone sodium succinate IC50 (concentration of drug that gave 50% inhibition of cell growth) values were 580.0 (1037.9) and 3237.1 (4627.3) nm, respectively. The ratio of prednisolone IC50/prednisolone sodium succinate IC50 ranged from 0.005 to 0.230. Thus, prednisolone sodium succinate potency was markedly lower than that of prednisolone. After incubation of PBMCs with 100 ,m prednisolone sodium succinate, 22.7,42.9 ,m prednisolone was liberated into the culture medium, as determined by HPLC. The ratio of prednisolone liberation from prednisolone sodium succinate was not affected by the presence of fetal bovine serum or PBMC, or both, in the culture medium. These results suggested that the PBMC-suppressive effects of prednisolone sodium succinate might be due, at least partially, to prednisolone liberated from prednisolone sodium succinate into the culture medium. Prednisolone sodium succinate can be converted to prednisolone in the absence of serum or PBMCs, but the ratio of this conversion was very slow (t£frac12; > 4 days). Therefore, impairment of the enzymatic conversion of prednisolone sodium succinate to prednisolone in some pathological conditions such as liver diseases may result in attenuation of the clinical efficacy of prednisolone sodium succinate. [source] Phenotypic and functional comparison of optimum culture conditions for upscaling of bone marrow-derived mesenchymal stem cellsJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 3 2009Rakhi Pal Abstract Human adult bone marrow-derived mesenchymal stem cells (MSCs) are a promising tool in the newly emerging avenue of regenerative medicine. MSCs have already been translated from basic research to clinical transplantation research. However, there is still a lack of consensus on the ideal method of culturing MSCs. Here we have compared different culture conditions of human MSCs with an attempt to preserve their characteristics and multi-lineage differentiation potential. We compare the different basal culture media DMEM-F12, DMEM-high glucose (DMEM-HG), DMEM-low glucose (DMEM-LG), knock-out DMEM (DMEM-KO) and Mesencult® on the proliferation rate, surface markers and differentiation potentials of MSCs. At every fifth passage until the 25th passage, the differentiation potential and the presence of a panel of surface markers was observed, using flow cytometry. We also compared the characteristics of human MSCs when cultured in reduced concentrations of fetal bovine serum (FBS), knockout serum replacement (KO-SR) and human plasma. Data indicate that the presence of serum is essential to sustain and propagate MSCs cultures. The choice of basal medium is equally important so as to preserve their characteristics and multipotent properties even after prolonged culture in vitro. With MSCs emerging as a popular tool for regenerative therapies in incurable diseases, it is essential to be able to obtain a large number of MSCs that continue to preserve their characteristics following passaging. The data reveal the optimum basal medium for prolonged culture of MSCs while retaining their ability to differentiate and hence this may be used for up-scaling to provide sufficient numbers for transplantation. Copyright © 2009 John Wiley & Sons, Ltd. [source] Clinicopathologic Evaluation of Hepatic Lipidosis in Periparturient Dairy CattleJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 4 2007Emmanouil Kalaitzakis Background: Fatty change of the liver (FCL) is very common in dairy cattle periparturiently. Many laboratory methods have been implicated in order to assist the diagnosis. Hypothesis: To investigate whether FCL in dairy cattle could be evaluated by assessment of ornithine carbamoyl transferase (OCT) by means of an assay modified for bovine serum, other enzyme activity, serum bile acids (SBA) concentration, or other biochemical constituents. Animals: A total of 187 dairy cattle were included: 106 were suspected to have liver dysfunction and were examined after referral by veterinarians; 70 were clinically healthy with mild FCL; and 11 were clinically healthy without FCL. Methods: Blood and liver biopsy samples were obtained after clinical examination. Histologic examination by light microscopy and classification of samples according to the severity of FCL was done, and total lipid and triglyceride concentration was measured. In serum, OCT, aspartate aminotransferase (AST), alanine aminotransferase (ALT), sorbitol dehydrogenase (SDH), glutamate dehydrogenase (GDH), alkaline phosphatase (ALP), and ,-glutamyltransferase (,-GT) activity as well as SBA, glucose, ketones, total bilirubin (tBIL), and nonesterified fatty acids (NEFA) concentration were measured. Results: OCT and AST activity and tBIL concentration correlate well with the degree of FCL. SBA concentration does not contribute well to FCL diagnosis. The majority of FCL cases appeared within the first 21 days-in-milk (DIM). The majority of moderate-to-severe and severe FCL cases arose in the first 7 DIM. Conclusions and Clinical Importance: Except for OCT, AST, and tBIL, none of the biochemical tests used, including SBA, had sufficient discriminatory power to differentiate reliably between mild and severe FCL because of poor sensitivity. A weak correlation between clinical signs and the extent of FCL was evident. [source] Cultured epithelial cells response to phototherapy with low intensity laser,LASERS IN SURGERY AND MEDICINE, Issue 4 2007Fernanda P. Eduardo PhD Abstract Background and Objectives Little is known about the intracellular response of epithelial cells to phototherapy. The aim of this in vitro study was to analyze the effect of phototherapy with low-energy lasers with different wavelengths and powers on cultured epithelial cell growth under different nutritional conditions. Study Design/Materials and Methods Epithelial cell cultures (Vero cell line) grown in nutritional deficit in culture medium supplemented with 2% fetal bovine serum (FBS) were irradiated with low-energy laser from one to three times with a GaAlAs laser (660 nm) and InGaAlP (780 nm), 40 and 70 mW, respectively, with 3 or 5 J/cm2. Cell growth was indirectly assessed by measuring the cell mitochondrial activity. Results Nonirradiated cell cultures grown in nutritional regular medium supplemented with 10% FBS produced higher cell growth than all cultures grown in nutritional deficit irradiated or not. The overall cell growth of cultures grown under nutritionally deficit conditions was significantly improved especially when irradiated with 780 nm for three times. Conclusions Phototherapy with the laser parameters tested increases epithelial cell growth rate for cells stressed by growth under nutritionally deficient states. This cell growth improvement is directly proportional to the number of irradiations; however, was not enough to reach the full cell growth potential rate of Vero epithelial cell line observed when growing under nutritional regular condition. Lasers Surg. Med. 39: 365,372, 2007. © 2007 Wiley-Liss, Inc. [source] A Novel Micellar PEGylated Hyperbranched Polyester as a Prospective Drug Delivery System for PaclitaxelMACROMOLECULAR BIOSCIENCE, Issue 9 2008Christina Kontoyianni Abstract A hyperbranched aliphatic polyester has been functionalized with PEG chains to afford a novel water-soluble BH40-PEG polymer which exhibits unimolecular micellar properties, and is therefore appropriate for application as a drug-delivery system. The solubility of the anticancer drug paclitaxel was enhanced by a factor of 35, 110, 230, and 355 in aqueous solutions of BH40-PEG of 10, 30, 60, and 90 mg,·,mL,1, respectively. More than 50% of the drug is released at a steady rate and release is almost complete within 10 h. The toxicity of BH40-PEG was assessed in vitro with A549 human lung carcinoma cells and found to be nontoxic for 3 h incubation up to a 1.75 mg,·,mL,1 concentration while LD50 was 3.5 mg,·,mL,1. Finally, it was efficiently internalized in cells, primarily in the absence of foetal bovine serum, while confocal microscopy revealed the preferential localization of the compound in cell nuclei. [source] |