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Ex Vivo (ex + vivo)
Kinds of Ex Vivo Terms modified by Ex Vivo Selected AbstractsComparative IFN- , Secretion after Hatching by Bovine Blastocysts Derived Ex Vivo and Completely Produced In VitroREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2007JA Neira Contents The interferon-tau (IFN- ,) secretion levels after hatching by bovine blastocysts derived from in vitro maturated oocytes (Group A) and from in vivo (Group B) were investigated considering embryo quality. Only very homogeneous blastocysts of excellent or good quality were considered from day 7 of culture (Group A) and day 7 after artificial insemination with frozen-thawed from the same bull used for in vitro fertilization (Group B). All embryos were individually cultured into a 50 ,l droplet of synthetic oviduct fluid medium with 10% fetal calf serum. After 24-h culture both Group A (n =44) and B (n = 40) secreted <54 pm IFN- ,. After 48-, 72-, 96- and 120-h culture, Group A daily secreted 143 ± 24 pm IFN- , (n = 19) vs 85 ± 12 pm IFN- , (n = 21) for Group B (p < 0.01), 491 ± 128 pm IFN- , (n = 29) vs 216 ± 37 pm IFN- , (n = 23) (NS), 499 ± 135 pm IFN- , (n = 26) vs 353 ± 93 pm IFN- , (n = 21) (NS), 559 ± 136 pm IFN- , (n = 22) vs 333 ± 75 pm IFN- , (n = 20) (NS), respectively. Taken all together during 5 days, Group A produced per embryo 1690 ± 290 pm IFN- , (n = 22) vs 982 ± 182 pm IFN- , (n = 20) for Group B (p < 0.05). For all culture time there were sizable percentages of embryos that did not produce concentrations of IFN- , above a certain cut-off level, and as such were not used to compute the means. In respect of the embryo quality whatever the groups after days 7,12 of culture, IFN- , secretions were 1815 ± 453 pm (n = 10) for the embryos of excellent quality vs 1356 ± 200 pm (n = 28) for those of good quality (NS) and 360 ± 188 pm (n = 4) (p < 0.05) for embryos of fair quality. A positive relationship between IFN- , production and in vitro development of quality I embryos was observed, whatever the embryos origins and, the embryos completely produced in vitro secreted more IFN- , than the embryos produced in vivo. [source] Vectorization of Harungana madagascariensis Lam. ex Poir. (Hypericaceae) ethanolic leaf extract by using PLG-nanoparticles: antibacterial activity assessmentDRUG DEVELOPMENT RESEARCH, Issue 1 2005B. Moulari Abstract This study was undertaken to compare the in vitro and ex vivo antibacterial activity of an ethanolic Harungana madagascariensis leaf extract (HLE) incorporated into poly (D,L -lactide-co,glycolide) nanoparticles (HLE -PLG-NP). Two concentrations of HLE (500 and 1,000,µg/mL) for the in vitro study and one concentration (500 µg/mL) for the ex vivo study were compared using two gram-positive bacterial strains (Micrococcus luteus and Staphylococcus epidermidis), and one gram-negative bacterial strain (Moraxella sp.). The ex vivo antibacterial activity was evaluated on S. epidermidis CIP 55109 (SE) using an artificial contamination method. SE was inoculated for 12 h onto human skin fragment surfaces treated for 5,min either with HLE loaded, unloaded PLG-NP, or HLE solution. In vitro, the two preparations inhibited completely the growth of all bacterial strains at 1,000,µg/mL. However, the HLE -PLG-NP had a significant antibacterial activity against SE (18.4±1.8,0.4±0.2 CFU/mL, P<0.05), and a marked antibacterial effect against M. luteus (ML) and Moraxella sp. (Msp) compared to HLE solution at 500 µg/mL. Ex vivo, HLE -PLG-NP at 500,µg/mL reduced viable bacteria (6.3,4.8 log10), compared to the HLE solution (6.3,5.5 log10) after 4 h artificial contamination (P<0.05). A thin layer chromatography study of both HLE solution and HLE -PLG-NP showed that among the seven components found on the chromatogram of the HLE solution, only two were present on the nanoparticles, one including a flavonoid heteroside fraction responsible for the antibacterial properties. The incorporation of the HLE into a colloidal carrier improved antibacterial performance. Drug Dev. Res. 65:26,33, 2005. © 2005 Wiley-Liss, Inc. [source] Influence of factor IX on overall plasma coagulability and fibrinolytic potential as measured by global assay: monitoring in haemophilia BHAEMOPHILIA, Issue 1 2008N. A. GOLDENBERG Summary., We sought to determine the influence of factor IX (FIX) deficiency upon overall coagulative and fibrinolytic capacities in plasma using the clot formation and lysis (CloFAL) assay, and to investigate the role of this global assay as an adjunctive monitoring tool in haemophilia B. CloFAL assay parameters were measured in vitro in platelet-poor plasma in relation to FIX activity and antigen (FIX:Ag), and were determined ex vivo among FIX-deficient patients (n = 41) in comparison to healthy individuals (n = 48). Supplementation of FIX-deficient plasma with FIX in vitro demonstrated a non-linear concentration dependence of FIX upon overall plasma coagulability. Ex vivo, coagulability was significantly decreased in FIX-deficient vs. healthy subjects among adults [median coagulation index (CI): 4% vs. 104% respectively; P < 0.001] and children (median CI: 9% vs. 63%; P < 0.001). Fibrinolytic capacity was increased in adult FIX-deficient vs. healthy subjects (median fibrinolytic index: 216% vs. 125%, respectively, P < 0.001), and was supported by a trend in shortened euglobulin lysis time (ELT). Severe haemophilia B patients showed heterogeneity in aberrant CloFAL assay waveforms, influenced partly by FIX:Ag levels. Patients with relatively preserved FIX:Ag (i.e. dysfunctional FIX) exhibited a shorter time to maximal amplitude in clot formation than those with type I deficiency. During patient treatment monitoring, markedly hypocoagulable CloFAL assay waveforms normalized following 100% correction with infused FIX. The CloFAL global assay detects FIX deficiency, demonstrates differences in coagulability between dysfunctional FIX and type I deficiency, and appears useful as an adjunctive test to routine FIX measurement in monitoring haemophilia B treatment. [source] Ex vivo expanded cord blood CD4 T lymphocytes exhibit a distinct expression profile of cytokine-related genes from those of peripheral blood originIMMUNOLOGY, Issue 3 2009Yoshitaka Miyagawa Summary With an increase in the importance of umbilical cord blood (CB) as an alternative source of haematopoietic progenitors for allogenic transplantation, donor lymphocyte infusion (DLI) with donor CB-derived activated CD4+ T cells in the unrelated CB transplantation setting is expected to be of increased usefulness as a direct approach for improving post-transplant immune function. To clarify the characteristics of activated CD4+ T cells derived from CB, we investigated their mRNA expression profiles and compared them with those of peripheral blood (PB)-derived activated CD4+ T cells. Based on the results of a DNA microarray analysis and quantitative real-time reverse transcriptase,polymerase chain reaction (RT-PCR), a relatively high level of forkhead box protein 3 (Foxp3) gene expression and a relatively low level of interleukin (IL)-17 gene expression were revealed to be significant features of the gene expression profile of CB-derived activated CD4+ T cells. Flow cytometric analysis further revealed protein expression of Foxp3 in a portion of CB-derived activated CD4+ T cells. The low level of retinoic acid receptor-related orphan receptor , isoform t (ROR,t) gene expression in CB-derived activated CD4+ T cells was speculated to be responsible for the low level of IL-17 gene expression. Our data indicate a difference in gene expression between CD4+ T cells from CB and those from PB. The findings of Foxp3 expression, a characteristic of regulatory T cells, and a low level of IL-17 gene expression suggest that CB-derived CD4+ T cells may be a more appropriate source for DLI. [source] Strontium Ranelate Treatment Improves Trabecular and Cortical Intrinsic Bone Tissue Quality, a Determinant of Bone Strength,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 9 2007Patrick Ammann MD Abstract Beside its influence on determinants of bone strength (geometry, microarchitecture), which is likely to be related to a cellular effect, strontium ranelate improves bone tissue quality as evaluated by nanoindentation, increasing elastic modulus, hardness, and dissipated energy in vertebrae of rats treated for 104 wk with daily dose from 0 to 900 mg/kg. Introduction: We previously showed that strontium ranelate treatment improves the mechanical properties of the vertebral body and long bone midshaft in intact rats. The increased energy to failure obtained with strontium ranelate is essentially caused by an increase in plastic energy, suggesting that bone formed during treatment can withstand greater deformation before fracture. In the bone mineral phase, strontium is mainly located in the hydrated shell and could thus potentially influence intrinsic bone tissue quality. Materials and Methods: To study whether strontium ranelate treatment could positively influence intrinsic bone tissue quality (elastic modulus, hardness, and dissipated energy), nanoindentation tests were performed at the level of trabecular nodes and cortex under physiological or dry conditions in vertebrae of rats treated for 104 wk with strontium ranelate at a daily dose of 0, 225, 450, or 900 mg/kg (n = 12 per group). Ex vivo ,CT measurements and axial compression tests of adjacent vertebral bodies were also performed. Significance of difference was evaluated using ANOVA. Results: In agreement with previous results, strontium ranelate (900 mg/kg/d) significantly increased versus controls in maximal load (+23%), total energy (+71%), and plastic energy (+143%). At the level of trabecular bone, strontium ranelate treatment resulted in a significant increase in elastic modulus (+15.1%, p < 0.01), hardness (+11.5%, p < 0.05), and dissipated energy (+16.2%, p < 0.001) versus controls in physiological, but not in dry, conditions. The effect was less pronounced in cortex. Conclusions: These results show for the first time a direct action of strontium ranelate on bone tissue quality. Beside its shown influence on classical determinants of bone strength (geometry, microarchitecture), which is likely to be related to a cellular effect, strontium ranelate improves bone tissue quality. This could contribute to the increase in bone strength and thus be involved in the reduction of fracture risk in postmenopausal osteoporotic patients treated with strontium ranelate. [source] Pharmacokinetics and pharmacokinetic/pharmacodynamic integration of marbofloxacin in calf serum, exudate and transudateJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 3 2002F. SHOJAEE ALIABADI Aliabadi, F. S., Lees, P. Pharmacokinetics and pharmacokinetic/pharmacodynamic integration of marbofloxacin in calf serum, exudate and transudate. J. vet. Pharmacol. Therap.25, 161,174. Marbofloxacin is a fluoroquinolone antimicrobial drug used in cattle for the treatment of respiratory infections. In this investigation the pharmacokinetics (PK) of marbofloxacin were determined after intravenous and intramuscular dosing at a dosage of 2 mg/kg. In addition the ex vivo pharmacodynamics (PD) of the drug were determined in serum and three types of tissue cage fluid (transudate, inflammatory exudate generated by carrageenan and exudate generated by lipopolysaccharide). Marbofloxacin PK was characterized by a high volume of distribution after dosing by both routes (1.28 L/kg intravenous and 1.25 L/kg intramuscular). Corresponding area under the concentration,time curve (AUC) and elimination half-life (t½el) values were 9.99 and 10.11 ,g h/mL and 4.23 and 4.33 h, respectively. Values of AUC for carrageenan-induced exudate, lipopolysaccharide-induced exudate and transudate were, respectively, 8.28, 7.83 and 7.75 ,g h/mL after intravenous and 8.84, 8.53 and 8.52 ,g h/mL after intramuscular dosing. Maximum concentration (Cmax) values were similar for the three tissue cage fluids after intravenous and intramuscular dosing. For in vivo PK data values of AUC: minimum inhibitory concentration (MIC) (AUIC) ratio for serum were 250 and 253, respectively, after intravenous and intramuscular dosing of marbofloxacin against a pathogenic strain of Mannheimia haemolytica (MIC=0.04 ,g/mL). For all tissue cage fluids AUIC values were >194 and >213 after intravenous and intramuscular dosing, and Cmax/MIC ratios were 9 or greater, indicating a likely high level of effectiveness in clinical infections caused by M. haemolytica of MIC 0.04 ,g/mL or less. This was confirmed by both in vitro (serum) and ex vivo (serum, exudate and transudate) measurements, which demonstrated a concentration-dependent killing profile for marbofloxacin against M. haemolytica. Ex vivo, after 24-h incubation, virtually all bacteria were killed (<10 cfu/mL) in all samples collected up to 9 h (serum), 24 h (carrageenan-induced exudate and transudate) and 36 h (lipopolysaccharide-induced exudate). Application of the sigmoid Emax equation to the ex vivo antibacterial data provided, for serum, AUIC24 h values of 37.1 for bacteriostasis, 46.3 for bactericidal activity and 119.6 for elimination of bacteria. These data may be used as a rational basis for setting dosing schedules which optimize clinical efficacy and minimize the opportunities for emergence of resistant organisms. [source] Ex vivo and in vivo evaluation of laser-induced thermotherapy for nodular thyroid diseaseLASERS IN SURGERY AND MEDICINE, Issue 7 2009Jörg-P. Abstract Background and Objective The prevalence of thyroid nodules ranges between 2% and 60% depending on the population studied. However, minimally invasive procedures like laser-induced thermotherapy (LITT) are increasingly used to treat tumors of parenchymatous organs and seem to be suitable for singular thyroid nodules as well. Their successful clinical application depends on the induction of sufficiently large lesions and a knowledge of the energy parameters required for complete thermal ablation. The aim of this study was to establish a dose,response relationship for LITT of thyroid nodules. Materials and Methods Thermal lesions were induced in healthy porcine thyroid glands ex vivo (n,=,110) and in vivo (n,=,10) using an Nd:YAG laser (1,064,nm). Laser energy was applied for 300,seconds in a power range of 10,20,W. During the ablation, continuous temperature measurement at a distance of 5 and 10,mm from the applicator was performed. The lesions were longitudinally and transversally measured, and the volume was calculated. Furthermore, enzyme histochemical analysis of the thyroid tissue was performed. Results The maximum inducible lesion volumes were between 0.74,±,0.18,cm3 at a laser power of 10,W and 3.80,±,0.41,cm3 at 20,W. The maximum temperatures after ablation were between 72.9,±,2.9°C (10,W) and 112.9,±,9.2°C (20,W) at a distance of 5,mm and between 49.5,±,2.2°C (10,W) and 73.2,±,6.7°C (20,W) at a distance of 10,mm from the applicator. The histochemical analysis demonstrates a complete loss of NADPH dehydrogenase activity in thermal lesions as a sign of irreversible cell damage. Conclusions This study is the first to demonstrate a dose,response relationship for LITT of thyroid tissue. LITT is suitable for singular thyroid nodules and induces reproducible clinically relevant lesions with irreversible cell damage in an appropriate application time. Lasers Surg. Med. 41:479,486, 2009. © 2009 Wiley-Liss, Inc. [source] Simulated reflux decreases vocal fold epithelial barrier resistance,,THE LARYNGOSCOPE, Issue 8 2010CF-SLP, Elizabeth Erickson MS Abstract Objectives/Hypothesis: The vocal fold epithelium provides a barrier to the entry of inhaled and systemic challenges. However, the location of the epithelium makes it vulnerable to damage. Past research suggests, but does not directly demonstrate, that exposure to gastric reflux adversely affects the function of the epithelial barrier. Understanding the nature of reflux-induced epithelial barrier dysfunction is necessary to better recognize the mechanisms for vocal fold susceptibility to this disease. Therefore, we examined the effects of physiologically relevant reflux challenges on vocal fold transepithelial resistance and gross epithelial and subepithelial appearance. Study Design: Ex vivo, mixed design with between-group and repeated-measures analyses. Methods: Healthy, native porcine vocal folds (N = 52) were exposed to physiologically relevant acidic pepsin, acid-only, or pepsin-only challenges and examined with electrophysiology and light microscopy. For all challenges, vocal folds exposed to a neutral pH served as control. Results: Acidic pepsin and acid-only challenges, but not pepsin-only or control challenges significantly reduced transepithelial resistance within 30 minutes. Reductions in transepithelial resistance were irreversible. Challenge exposure produced minimal gross changes in vocal fold epithelial or subepithelial appearance as evidenced by light microscopy. Conclusions: These findings demonstrate that acidic environments characteristic of gastric reflux compromise epithelial barrier function without gross structural changes. In healthy, native vocal folds, reductions in transepithelial resistance could reflect reflux-related epithelial disruption. These results might guide the development of pharmacologic and therapeutic recommendations for patients with reflux, such as continued acid-suppression therapy and patient antireflux behavioral education. Laryngoscope, 2010 [source] MAGNETIC RESONANCE IN SURGICAL ONCOLOGY: II , LITERATURE REVIEWANZ JOURNAL OF SURGERY, Issue 6 2005Laurence Gluch Ex vivo and in vivo applications of magnetic resonance spectroscopy have been developed which aid in distinguishing malignant from normal tissues. Studies of breast, colon, cervix, oesophageal and prostate cancer reveal both the successes and failings of present technology. Verification that these non-invasive tests might supplant conventional histology in obtaining spatial diagnostic and chemical prognostic information remains for the time being illusive. [source] Selective functional inhibition of JAK-3 is sufficient for efficacy in collagen-induced arthritis in miceARTHRITIS & RHEUMATISM, Issue 8 2010Tsung H. Lin Objective All ,-chain cytokines signal through JAK-3 and JAK-1 acting in tandem. We undertook this study to determine whether the JAK-3 selective inhibitor WYE-151650 would be sufficient to disrupt cytokine signaling and to ameliorate autoimmune disease pathology without inhibiting other pathways mediated by JAK-1, JAK-2, and Tyk-2. Methods JAK-3 kinase selective compounds were characterized by kinase assay and JAK-3,dependent (interleukin-2 [IL-2]) and ,independent (IL-6, granulocyte,macrophage colony-stimulating factor [GM-CSF]) cell-based assays measuring proliferation or STAT phosphorylation. In vivo, off-target signaling was measured by IL-22, and erythropoietin (EPO),mediated models, while on-target signaling was measured by IL-2,mediated signaling. Efficacy of JAK-3 inhibitors was determined using delayed-type hypersensitivity (DTH) and collagen-induced arthritis (CIA) models in mice. Results In vitro, WYE-151650 potently suppressed IL-2,induced STAT-5 phosphorylation and cell proliferation, while exhibiting 10,29-fold less activity against JAK-3,independent IL-6, or GM-CSF,induced STAT phosphorylation. Ex vivo, WYE-151650 suppressed IL-2,induced STAT phosphorylation, but not IL-6,induced STAT phosphorylation, as measured in whole blood. In vivo, WYE-151650 inhibited JAK-3,mediated IL-2,induced interferon-, production and decreased the natural killer cell population in mice, while not affecting IL-22,induced serum amyloid A production or EPO-induced reticulocytosis. WYE-151650 was efficacious in mouse DTH and CIA models. Conclusion In vitro, ex vivo, and in vivo assays demonstrate that WYE-151650 is efficacious in mouse CIA despite JAK-3 selectivity. These data question the need to broadly inhibit JAK-1,, JAK-2,, or Tyk-2,dependent cytokine pathways for efficacy. [source] Clinical scale ex vivo manufacture of neutrophils from hematopoietic progenitor cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2009Nicholas E. Timmins Abstract Dose-intensive chemotherapy results in an obligatory period of severe neutropenia during which patients are at high risk of infection. While patient support with donor neutrophils is possible, this option is restricted due to donor availability and logistic complications. To overcome these problems, we explored the possibility of large scale ex vivo manufacture of neutrophils from hematopoietic progenitor cells (HPC). CD34+ HPC isolated from umbilical cord blood (UCB) and mobilized peripheral blood (mPB) were expanded in serum-free medium supplemented with stem cell factor, granulocyte colony stimulating factor, and a thrombopoietin peptide mimetic. After 15 days of cultivation a 5,800-fold expansion in cell number was achieved for UCB, and up to 4,000-fold for mPB, comprising 40% and 60% mature neutrophils respectively. Ex vivo expanded neutrophils exhibited respiratory burst activity similar to that for donor neutrophils, and were capable of killing Candida albicans in vitro. These yields correspond to a more than 10-fold improvement over current methods, and are sufficient for the production of multiple neutrophil transfusion doses per HPC donation. To enable clinical scale manufacture, we adapted our protocol for use in a wave-type bioreactor at a volume of 10,L. This is the first demonstration of a large scale bioprocess suitable for routine manufacture of a mature blood cell product from HPC, and could enable prophylactic neutrophil support for chemotherapy patients. Biotechnol. Bioeng. 2009; 104: 832,840 © 2009 Wiley Periodicals, Inc. [source] Protective role of the antidiabetic drug metformin against chronic experimental pulmonary hypertensionBRITISH JOURNAL OF PHARMACOLOGY, Issue 5 2009C Agard Background and purpose:, Pulmonary arterial hypertension (PAH) is associated with increased contraction and proliferation of pulmonary vascular smooth muscle cells. The anti-diabetic drug metformin has been shown to have relaxant and anti-proliferation properties. We thus examined the effect of metformin in PAH. Experimental approach:, Metformin effects were analysed in hypoxia- and monocrotaline-induced PAH in rats. Ex vivo and in vitro analyses were performed in lungs, pulmonary artery rings and cells. Key results:, In hypoxia- and monocrotaline-induced PAH, the changes in mean pulmonary arterial pressure and right heart hypertrophy were nearly normalized by metformin treatment (100 mg·kg,1·day,1). Pulmonary arterial remodelling occurring in both experimental models of PAH was also inhibited by metformin treatment. In rats with monocrotaline-induced PAH, treatment with metformin significantly increased survival. Metformin increased endothelial nitric oxide synthase phosphorylation and decreased Rho kinase activity in pulmonary artery from rats with PAH. These effects are associated with an improvement of carbachol-induced relaxation and reduction of phenylephrine-induced contraction of pulmonary artery. In addition, metformin inhibited mitogen-activated protein kinase activation and strongly reduced pulmonary arterial cell proliferation during PAH. In vitro, metformin directly inhibited pulmonary artery smooth muscle cell growth. Conclusions and implications:, Metformin protected against PAH, regardless of the initiating stimulus. This protective effect may be related to its anti-remodelling property involving improvement of endothelial function, vasodilatory and anti-proliferative actions. As metformin is currently prescribed to treat diabetic patients, assessment of its use as a therapy against PAH in humans should be easier. [source] Repolarization of the cardiac action potential.ACTA PHYSIOLOGICA, Issue 2010Does an increase in repolarization capacity constitute a new anti-arrhythmic principle? Abstract The cardiac action potential can be divided into five distinct phases designated phases 0,4. The exact shape of the action potential comes about primarily as an orchestrated function of ion channels. The present review will give an overview of ion channels involved in generating the cardiac action potential with special emphasis on potassium channels involved in phase 3 repolarization. In humans, these channels are primarily Kv11.1 (hERG1), Kv7.1 (KCNQ1) and Kir2.1 (KCNJ2) being the responsible ,-subunits for conducting IKr, IKs and IK1. An account will be given about molecular components, biophysical properties, regulation, interaction with other proteins and involvement in diseases. Both loss and gain of function of these currents are associated with different arrhythmogenic diseases. The second part of this review will therefore elucidate arrhythmias and subsequently focus on newly developed chemical entities having the ability to increase the activity of IKr, IKs and IK1. An evaluation will be given addressing the possibility that this novel class of compounds have the ability to constitute a new anti-arrhythmic principle. Experimental evidence from in vitro, ex vivo and in vivo settings will be included. Furthermore, conceptual differences between the short QT syndrome and IKr activation will be accounted for. [source] Cleansing without compromise: the impact of cleansers on the skin barrier and the technology of mild cleansingDERMATOLOGIC THERAPY, Issue 2004K. P. Ananthapadmanabhan ABSTRACT:, Cleanser technology has come a long way from merely cleansing to providing mildness and moisturizing benefits as well. It is known that harsh surfactants in cleansers can cause damage to skin proteins and lipids, leading to after-wash tightness, dryness, barrier damage, irritation, and even itch. In order for cleansers to provide skin-care benefits, they first must minimize surfactant damage to skin proteins and lipids. Secondly, they must deposit and deliver beneficial agents such as occlusives, skin lipids, and humectants under wash conditions to improve skin hydration, as well as mechanical and visual properties. While all surfactants tend to interact to some degree with lipids, their interaction with proteins can vary significantly, depending upon the nature of their functional head group. In vitro, ex vivo, and in vivo studies have shown that surfactants that cause significant skin irritation interact strongly with skin proteins. Based on this understanding, several surfactants and surfactant mixtures have been identified as "less irritating" mild surfactants because of their diminished interactions with skin proteins. Surfactants that interact minimally with both skin lipids and proteins are especially mild. Another factor that can aggravate surfactant-induced dryness and irritation is the pH of the cleanser. The present authors' recent studies demonstrate that high pH (pH 10) solutions, even in the absence of surfactants, can increase stratum corneum (SC) swelling and alter lipid rigidity, thereby suggesting that cleansers with neutral or acidic pH, close to SC-normal pH 5.5, may be potentially less damaging to the skin. Mildness enhancers and moisturizing agents such as lipids, occlusives, and humectants minimize damaging interactions between surfactants, and skin proteins and lipids, and thereby, reduce skin damage. In addition, these agents play an ameliorative role, replenishing the skin lipids lost during the wash period. The present review discusses the benefits of such agents and their respective roles in improving the overall health of the skin barrier. [source] Three-dimensional endoscopic ultrasonography for the assessment of early gastric carcinoma invasion: could it provide diagnostic innovations?DIGESTIVE ENDOSCOPY, Issue 2 2002EMAN A. SABET Background: This study aimed to evaluate a three-dimensional endoscopic ultrasonographic (3-D EUS) system in the assessment of the tumor invasion depth of early gastric carcinoma. Methods: Sixty-nine macroscopically early cancer lesions in 67 patients were recruited in an in vivo study. The surgically resected gastric specimens of 30 of them were re-examined in an ex vivo study. An Olympus 3-D EUS imaging system was employed in both studies. Diagnostic accuracy for tumor invasion depth was evaluated and compared with histopathological sections stained by H&E and Masson's trichrome stain. Reconstructed surface-rendering images were evaluated and compared with the endoscopic and macroscopic findings. Results: Three-dimensional EUS allowed rapid tomographic assessment of the lesions in both the in vivo and ex vivo studies. The accuracy of 3-D EUS for the assessment of tumor invasion depth was 87% in the in vivo study. The accuracy rate was significantly lower (P = 0.03) for the cancer lesions associated with ulcer fibrosis (74%) than for those with no fibrosis (97%). In the 30 subjects who underwent both studies, the accuracy rates were higher in the ex vivo than the in vivo study (94%vs 77% for all the lesions, and 93%vs 74% for cancers associated with fibrosis), but were not statistically significant. The rates of good surface-rendering images were 64% and 94% in the in vivo and ex vivo studies, respectively. The differences were attributed to the clearer dual-plane reconstruction images obtained in the ex vivo study in absence of motion artifacts. Conclusions: Three-dimensional EUS is a promising imaging technique for the assessment of tumor invasion depth of early gastric cancer. [source] The Effects of Ecstasy (MDMA) on Rat Liver BioenergeticsACADEMIC EMERGENCY MEDICINE, Issue 7 2004Daniel E. Rusyniak MD Abstract Objectives: Use of the drug ecstasy (3,4-methylenedioxymethamphetamine [MDMA]) can result in life-threatening hyperthermia. Agents that uncouple mitochondrial oxidative phosphorylation are known to cause severe hyperthermia. In the present study, the authors tested the hypothesis that MDMA directly uncouples oxidative phosphorylation in rat liver mitochondria. Methods: Effects on mitochondrial bioenergetics were assessed both in vitro and ex vivo. In vitro studies consisted of measuring the effects of MDMA (0.1,5.0 mmol/L) on states of respiration in isolated rat liver mitochondria and on mitochondrial membrane potential in a rat liver cell line. In ex vivo studies, mitochondrial rates of respiration were measured in the livers of rats one hour after treatment with MDMA (40 mg/kg subcutaneously). Results: With the in vitro mitochondrial preparations, only concentrations of 5 mmol/L MDMA showed evidence of uncoupling with a slight increase in state 4 respiration and a corresponding decrease in the respiratory control index. MDMA (0.1,5.0 mmol/L) failed to decrease the mitochondrial membrane potential in 3,3-dihexyloxacarbocyanide iodide,stained WB-344 cells after either one or 24 hours of incubation. Ex vivo rates of respiration obtained from the livers of rats one hour after treatment with MDMA (40 mg/kg subcutaneously) showed no evidence of mitochondrial uncoupling. Conclusions: These data suggest that while high concentrations of MDMA have some mild uncoupling effects in isolated mitochondria, these effects do not translate to cell culture or ex vivo studies in treated animals. These data do not support the view that the hyperthermia induced by MDMA is from a direct effect on mitochondrial oxidative phosphorylation. [source] Dentinogenic potential of the dental pulp: facts and hypothesesENDODONTIC TOPICS, Issue 1 2007DIMITRIOS TZIAFAS The aim of the present article is to discuss observations and hypotheses from different experimental approaches on the biological mechanisms underlying initiation of tertiary dentin formation and therapeutic control of pulp,dentinal regeneration. The specific dentinogenic potential of dental pulp cells in up-regulating the biosynthetic activity of primary odontoblasts (reactionary dentinogenesis) and differentiation into odontoblast-like cells (reparative dentinogenesis) is described. The role of biologically active matrices and molecules as signaling factors in the expression of the dentinogenic potential of dental pulp cells, in numerous ex vivo and in vivo models, is reviewed. Data are focused on the mechanisms by which the signaling molecules, in the presence of the appropriate pulp microenvironment and specific mechanical support, can induce competent pulpal cells in the acquisition of odontoblast-like cell phenotype and reparative dentin formation. The ability of tissue engineering to stimulate reconstruction of the amputated pulp,dentin complex offers exciting opportunities for the future. Advances in molecular biology and bioengineering research might thus be integrated into the clinical problems of endodontology. Received 13 February 2009; accepted 2 September 2009. [source] Magnetic resonance microscopy of the equine hoof wall: a study of resolution and potentialEQUINE VETERINARY JOURNAL, Issue 5 2006M. D. KELLER Summary Reasons for performing study: Obtaining magnetic resonance images of the inner hoof wall tissue at the microscopic level would enable early accurate diagnosis of laminitis and therefore more effective therapy. Objectives: To optimise magnetic resonance imaging (MRI) parameters in order to obtain the highest possible resolution of the structures beneath the equine hoof wall. Methods: Magnetic resonance microscopy (MRM) was performed in front feet from 6 cadaver horses using T2 -weighted fast spin echo (FSE-T2), and T1 -weighted gradient echo (GRE-T1) sequences. Results: In T2 weighted FSE images most of the stratum medium showed no signal, however the coronary, terminal and sole papillae were visible. The stratum lamellatum was clearly visible and primary epidermal lamellae could be differentiated from dermal lamellae. Conclusion: Most structures beneath the hoof wall were differentiated. Conventional scanners for diagnostic MRI in horses are low or high field. However this study used ultra-high field scanners currently not available for clinical use. Signal-to-noise ratio (S/N) increases as a function of field strength. An increase of spatial resolution of the image results in a decreased S/N. S/N can also be improved with better coils and the resolution of high field MRI scanners will increase as technology develops and surface array coils become more readily available. Potential relevance: Although MR images with microscopic resolution were obtained ex vivo, this study demonstrates the potential for detection of lamellar pathology as it occurs. Early recognition of the development of laminitis to instigate effective therapy at an earlier stage and may improve the outcome for laminitic horses. Clinical MR is now readily available at 3 T, while 4 T, 7 T and 9 T systems are being used for human whole body applications. [source] Natural killer cells in viral hepatitis: facts and controversiesEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 9 2010Mario U. Mondelli Eur J Clin Invest 2010; 40 (9): 851,863 Abstract Background, Hepatitis B virus (HBV) and hepatitis C virus (HCV) are major human hepatotropic pathogens responsible for a large number of chronic infections worldwide. Their persistence is thought to result from inefficiencies of innate and adaptive immune responses; however, very little information is available on the former. Natural killer (NK) cells are a major component of innate immunity and their activity is tightly regulated by several inhibitory and activating receptors. Design, In this review, we examine controversial findings regarding the role of NK cells in the pathogenesis of acute and chronic liver disease caused by HCV and HBV. Results, Recent studies built up on technical advances to identify NK receptors and their functional correlates in this setting. While NK cells seem to behave correctly during acute hepatitis, it would appear that the NK cytotoxic potential is generally conserved in chronic hepatitis, if not increased in the case of HCV. In contrast, their ability to secrete antiviral cytokines such as interferon ex vivo or after cytokine stimulation is severely impaired. Conclusions, Current evidence suggests the existence of an NK cell functional dichotomy, which may contribute to virus persistence, while maintaining low-level chronic liver inflammation. The study of liver-infiltrating NK cells is still at the very beginning, but it is likely that it will shed more light on the role of this simple and at the same time complex innate immune cell in liver disease. [source] Ovariectomy increases vascular calcification via the OPG/RANKL cytokine signalling pathwayEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2008B. G. Choi ABSTRACT Background, Observational studies suggest a strong relationship between menopause and vascular calcification. Receptor activator of nuclear factor-,, ligand (RANKL) and osteoprotegerin (OPG) are critical regulators of bone remodelling and modulate vascular calcification. We assessed the hypothesis that ovariectomy increases vascular calcification via the OPG/RANKL axis. Materials and methods, Age-matched sexually mature rabbits were randomized to ovariectomy (OVX, n = 12) or sham procedure (SHAM, n = 12). One month post-procedure, atherosclerosis was induced by 15 months 0·2%-cholesterol diet and endothelial balloon denudations (at months 1 and 3). Aortic atherosclerosis was assessed in vivo by magnetic resonance imaging (MRI) at months 9 and 15. At sacrifice, aortas were harvested for ex vivo microcomputed tomography (µCT) and molecular analysis of the vascular tissue. Results, Vascular calcification density and calcific particle number were significantly greater in OVX than SHAM (8·4 ± 2·8 vs. 1·9 ± 0·6 mg cm,3, P = 0·042, and 94 ± 26 vs. 33 ± 7 particles cm,3, P = 0·046, respectively). Calcification morphology, as assessed by the arc angle subtended by the largest calcific particle, showed no difference between groups (OVX 33 ± 7° vs. SHAM 33 ± 5°, P = 0·99). By Western blot analysis, OVX increased the vascular OPG:RANKL ratio by 66%, P = 0·029, primarily by decreasing RANKL (P = 0·019). At month 9, MRI demonstrated no difference in atheroma volume between OVX and SHAM, and no significant change was seen by the end of the study. Conclusions, In contrast to bone, vascular OPG:RANKL ratio increased in response to ovariectomy with a corresponding fourfold increase in arterial calcification. This diametrical organ-specific response may explain the comorbid association of osteoporosis with calcifying atherosclerosis in post-menopausal women. [source] Resveratrol modulates apoptosis and oxidation in human blood mononuclear cellsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 9 2003G. A. Losa Abstract Background, We examined the effect of resveratrol (RS), a nonflavonoid polyphenolic phytoalexin found in grapes and red wine, and RS coincubated with the oxidant 2-deoxy-D-ribose (dR), on apoptosis and on the oxidative metabolic status of normal human peripheral blood mononuclear cells (PBMNCs) isolated ex vivo from healthy donors. Material and methods, Apoptosis was measured by changes of membrane permeability to propidium iodide (PI), plasma membrane exposure of phosphatidylserine (PS) and intracellular caspase activity. Oxidative status was assessed by recording the intracellular glutathione concentration (GSH), the activities of the enzymes y -glutamyltransferase (y- GT) and glutathione-S-transferase (GST), and intracellular lipid peroxidation (MDA). Results, Neither apoptotic nor oxidative parameters were affected by culturing PBMNCs in medium containing RS up to 20 µM for 5 days, while the frequency of cells with intermediate permeability to PI (17% ± 5) increased at 50 µM of RS. Thus resveratrol was slightly toxic, but there was little apoptosis in these cells. Peripheral blood mononuclear cells were also grown first in medium plus RS for 24 h and then for 96 h in medium containing RS plus 10 mM of dR, an oxidant sugar that is apoptogenic for human lymphocytes. The apoptotic changes triggered by dR were counteracted by the phytoalexin in a dose-dependent manner, but RS activity was absent at the lowest concentration (5 µM) and significantly reduced at the highest concentration used (50 µM). In PBMNCs coincubated with 20 µM of RS and 10 mM of dR the antioxidant effect of RS manifested with a significant reduction of caspases-3, -8, y- GT, GST activities and MDA content. Conclusions, Peripheral blood mononuclear cells acquire antioxidant capacity when treated with RS. Grape resveratrol may make a useful dietary supplement for minimizing oxidative injury in immune-perturbed states and human chronic degenerative diseases. [source] Phenotypic analysis of human peripheral blood regulatory T cells (CD4+FOXP3+CD127lo/,) ex vivo and after in vitro restimulation with malaria antigensEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 1 2010Olivia C. Finney Abstract Regulatory T cells (Treg) play crucial roles in regulating autoimmune responses and immunity to tumors and infectious diseases. However, numerous subpopulations of Treg are now being described and the utility of various Treg markers is being reassessed. Here we report the results of a detailed phenotypic comparison of two supposedly regulatory human T-cell populations, namely CD4+FOXP3+ T cells and CD4+CD25hi T cells. We find that CD4+FOXP3+ cells are extremely heterogeneous with respect to CD25 expression and that FOXP3+ and CD25hi CD4+ T cells differ in their expression of chemokine receptors (CCR), CD95 and Bcl-2, suggestive of distinct migration characteristics and susceptibility to apoptosis. Further, we propose that CD25 expression should be regarded as an activation marker rather than as a defining marker of Treg. Lastly, CD4+FOXP3+ T cells activated in vitro with malaria antigen expressed the highest levels of CCR4 and CD95, and the lowest levels of CCR7, indicating that they are most likely generated from effector memory cells during an immune response and rapidly succumb to apoptosis at the end of the response. [source] CD8+ T-cell responses to Theileria parva are preferentially directed to a single dominant antigen: Implications for parasite strain-specific immunityEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 9 2009Niall D. MacHugh Abstract Although immunodominance of CD8+ T-cell responses is a well-recognised feature of viral infections, its role in responses to more antigenically complex pathogens is less clear. In previous studies we have observed that CD8+ T-cell responses to Theileria parva exhibit different patterns of parasite strain specificity in cattle of different MHC genotypes. In the current study, we demonstrated that animals homozygous for the A10 and A18 MHC haplotypes have detectable responses to only one of 5 T. parva antigens. Over 60% of the responding T cells from the A18+ and A10+ animals recognised defined epitopes in the Tp1 and Tp2 antigens, respectively. Comparison of T-cell receptor , chain expression profiles of CD8+ T-cell lines and CD8+ T cells harvested ex vivo confirmed that the composition of the T-cell lines was representative of the in vivo memory CD8+ T-cell populations. Analysis of the Tp1 and Tp2 antigens revealed sequence polymorphism, which was reflected by differential recognition by T-cell lines. In conclusion, we have demonstrated a profound immunodominance in the CD8+ T-cell response to T. parva, which we propose is a major determinant of the parasite strain specificity of the response and hence immune protection. [source] IL-15 is critical for the maintenance and innate functions of self-specific CD8+ T cellsEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 7 2009Momoe Itsumi Abstract IL-15 is a pleiotropic cytokine involved in host defense as well as autoimmunity. IL-15-deficient mice show a decrease of memory phenotype (MP) CD8+ T cells, which develop naturally in naïve mice and whose origin is unclear. It has been shown that self-specific CD8+ T cells developed in male H-Y antigen-specific TCR transgenic mice share many similarities with naturally occurring MP CD8+ T cells in normal mice. In this study, we found that H-Y antigen-specific CD8+ T cells in male but not female mice decreased when they were crossed with IL-15-deficient mice, mainly due to impaired peripheral maintenance. The self-specific TCR transgenic CD8+ T cells developed in IL-15-deficient mice showed altered surface phenotypes and reduced effector functions ex vivo. Bystander activation of the self-specific CD8+ T cells was induced in vivo during infection with Listeria monocytogenes, in which proliferation but not IFN-, production was IL-15-dependent. These results indicated important roles for IL-15 in the maintenance and functions of self-specific CD8+ T cells, which may be included in the naturally occurring MP CD8+ T-cell population in naïve normal mice and participate in innate host defense responses. [source] Decreased specific CD8+ T,cell cross-reactivity of antigen recognition following vaccination with Melan-A peptideEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 7 2006Victor Appay Abstract The aim of T,cell vaccines is the expansion of antigen-specific T,cells able to confer immune protection against pathogens or tumors. Although increase in absolute cell numbers, effector functions and TCR repertoire of vaccine-induced T,cells are often evaluated, their reactivity for the cognate antigen versus their cross-reactive potential is rarely considered. In fact, little information is available regarding the influence of vaccines on T,cell fine specificity of antigen recognition despite the impact that this feature may have in protective immunity. To shed light on the cross-reactive potential of vaccine-induced cells, we analyzed the reactivity of CD8+ T,cells following vaccination of HLA-A2+ melanoma patients with Melan-A peptide, incomplete Freund's adjuvant and CpG-oligodeoxynucleotide adjuvant, which was shown to induce strong expansion of Melan-A-reactive CD8+ T,cells in vivo. A collection of predicted Melan-A cross-reactive peptides, identified from a combinatorial peptide library, was used to probe functional antigen recognition of PBMC ex vivo and Melan-A-reactive CD8+ T,cell clones. While Melan-A-reactive CD8+ T,cells prior to vaccination are usually constituted of widely cross-reactive naive cells, we show that peptide vaccination resulted in expansion of memory T,cells displaying a reactivity predominantly restricted to the antigen of interest. Importantly, these cells are tumor-reactive. [source] The Shiga toxin B-subunit targets antigen in vivo to dendritic cells and elicits anti-tumor immunityEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 5 2006Benoit Vingert Abstract The non-toxic B-subunit of Shiga toxin (STxB) interacts with the glycolipid Gb3, which is preferentially expressed on dendritic cells (DC) and B cells. After administration of STxB chemically coupled to OVA (STxB-OVA) in mice, we showed that the immunodominant OVA257,264 peptide restricted by Kb molecules is specifically presented by CD11c+CD8,, DC, some of them displaying a mature phenotype. Using mice carrying a transgene encoding a diphtheria toxin receptor (DTR) under the control of the murine CD11c promoter, which allows inducible ablation of DC, we showed that DC are required for efficient priming of CTL after STxB-OVA vaccination. Immunization of mice with STxB-OVA induced OVA-specific CD8+ T cells detected ex vivo; these cells were long lasting, since they could be detected even 91,days after the last immunization and were composed of both central and memory T cells. Vaccination of mice with STxB-OVA and STxB coupled to E7, a protein derived from HPV16, inhibited tumor growth in prophylactic and therapeutic experiments. This effect was mainly mediated by CD8+ T cells. STxB therefore appears to be a powerful carrier directly targeting DC in vivo, resulting in a strong and durable CTL response associated with tumor protection. [source] Mechanism of modulation of T cell responses by N-palmitoylated peptidesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 12 2004Clara Bueno Abstract Small structural changes in the antigenic peptides recognized by TCR can alter the biological properties of those peptides and convert them into weak agonists, partial agonists, or antagonists of these receptors. These altered peptide ligands (APL) are usually generated by conservative amino acid substitutions at TCR contact residues. Here, we show that APL with therapeutic properties can also be generated by attachment of palmitic acid at the N terminus of the peptide without the need to modify the peptide's primary sequence. Using N-palmitoylated pigeon cytochrome-c peptide 81,104 (PALPCC81,104), we were able to induce T cell hyporesponsiveness to the wild-type peptide in vitro. More importantly, administration of the PALPCC81,104 to mice reduced the responsiveness to the native peptide when tested ex vivo. Biochemical and functional experiments indicated that the action of N-palmitoylated peptides was due to the conversion of the native peptide into a weak agonist that could then induce T cell anergy. Our results demonstrate that N-palmitoylation of antigenic peptides is a feasible strategy to generate APL, as it avoids the need to screen multiple amino acid variants of each specific antigen to identify those with therapeutic properties. [source] Oxidative stability of Echium plantagineum seed oil bodiesEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2010David A. Gray Abstract Echium plantagineum seed contains a highly polyunsaturated oil (approximately 14% linoleic acid, 10% ,-linolenic acid, 33% ,-linolenic acid and 14% stearidonic acid); almost half of the fatty acids are omega-3 fatty acids, so there is an interest in the possible health benefits of this oil, which, once extracted, is prone to oxidation. For the first time in reported literature, oil bodies (OBs), the organelles that store the oil in mature seed, were recovered from E. plantagineum seeds. The oxidative stability of these organelles ex vivo, dispersed in an aqueous continuous phase, was tested against processed E. plantagineum oil emulsions stabilised with either SDS or Tween 20. For both primary and secondary oxidation products the OBs were the most stable form of dispersed oil, and the dispersed systems were all more stable than bulk E. plantagineum oil after incubating at 40°C for 7 days. The possible reasons for the enhanced chemical stability of E. plantagineum OBs are explored in this paper. Practical applications: OBs, the natural store of oil in oilseeds, can be recovered from seeds intact and are relatively stable to oxidation ex vivo. Echium seed OBs, enriched in physiologically active omega-3 fatty acids, therefore offer an attractive alternative to traditional oil extraction methods and overcome the need to encapsulate the omega-3 rich oil. [source] Long-term depression activates transcription of immediate early transcription factor genes: involvement of serum response factor/Elk-1EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2006Antje Lindecke Abstract Long-term depression (LTD) is one of the paradigms used in vivo or ex vivo for studying memory formation. In order to identify genes with potential relevance for memory formation we used mouse organotypic hippocampal slice cultures in which chemical LTD was induced by applications of 3,5-dihydroxyphenylglycine (DHPG). The induction of chemical LTD was robust, as monitored electrophysiologically. Gene expression analysis after chemical LTD induction was performed using cDNA microarrays containing >7000 probes. The DHPG-induced expression of immediate early genes (c-fos, junB, egr1 and nr4a1) was subsequently verified by TaqMan polymerase chain reaction. Bioinformatic analysis suggested a common regulator element [serum response factor (SRF)/Elk-1 binding sites] within the promoter region of these genes. Indeed, here we could show a DHPG-dependent binding of SRF at the SRF response element (SRE) site within the promoter region of c-fos and junB. However, SRF binding to egr1 promoter sites was constitutive. The phosphorylation of the ternary complex factor Elk-1 and its localization in the nucleus of hippocampal neurones after DHPG treatment was shown by immunofluorescence using a phosphospecific antibody. We suggest that LTD leads to SRF/Elk-1-regulated gene expression of immediate early transcription factors, which could in turn promote a second broader wave of gene expression. [source] A disaccharide derived from chondroitin sulphate proteoglycan promotes central nervous system repair in rats and mice,EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2004Asya Rolls Abstract Chondroitin sulphate proteoglycan (CSPG) inhibits axonal regeneration in the central nervous system (CNS) and its local degradation promotes repair. We postulated that the enzymatic degradation of CSPG generates reparative products. Here we show that an enzymatic degradation product of CSPG, a specific disaccharide (CSPG-DS), promoted CNS recovery by modulating both neuronal and microglial behaviour. In neurons, acting via a mechanism that involves the PKC, and PYK2 intracellular signalling pathways, CSPG-DS induced neurite outgrowth and protected against neuronal toxicity and axonal collapse in vitro. In microglia, via a mechanism that involves ERK1/2 and PYK2, CSPG-DS evoked a response that allowed these cells to manifest a neuroprotective phenotype ex vivo. In vivo, systemically or locally injected CSPG-DS protected neurons in mice subjected to glutamate or aggregated ,-amyloid intoxication. Our results suggest that treatment with CSPG-DS might provide a way to promote post-traumatic recovery, via multiple cellular targets. [source] | |||||||||||||||||||||||||||||||||||||||||||