990 resultados para SERUM-CALCIUM


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Rapport de synthèseObjectifsLe retard de croissance intrautérin (RCIU) est un problème affectant 10% des grossesses et est associé à une morbidité périnatale importante. Dans environ 80% des cas, une étiologie ou un facteur de risque majeur peuvent être identifiés. Mais près de 20% des cas sont considérés comme inexpliqués. La heat shock protéine 60kDa (HSP60) est une protéine fortement immunogène dont la synthèse est considérablement augmentée lors de conditions non- physiologiques. Les HSP60 humaines et bactériennes partagent un haut degré d'homologie de séquence ce qui peut engendrer une maladie auto-immune à la suite d'une infection bactérienne. Nous avons supposé que les RCIU inexpliqués pourraient être la conséquence d'une sensibilisation à l'HSP60 humaine.MéthodesLes RCIU inexpliqués ont été identifiés par mesure échographique avec un doppler normal, sans anomalies décelables chez la mère ou le foetus. Les sera foetaux ont été obtenus par cordocentèse, effectuée lors d'analyse du caryotype en cas de RCIU inexpliqué (groupe d'étude) ou pour le dépistage d'une incompatibilité Rhésus (groupe témoin). Ils ont été testés pour l'antigène HSP60 et les IgG et IgM anti-HSP60 par ELISA ainsi que pour d'autres paramètres immunitaires et hématologiques.RésultatsLes paramètres maternels sont similaires entre les 12 cas du groupe d'étude et les 23 cas du groupe contrôle. L'âge gestationnel moyen lors de la cordocentèse est de 29 semaines. Les IgM anti-HSP60 sont détectés dans 12 cas d'étude (100%) mais dans aucun cas contrôle (p <0,00017), les IgG anti-HSP60 dans 7 cas d'étude (58%) et un seul dans le groupe contrôle (p <0,001). Trois des quatre cas avec les taux d'IgM les plus élevés sont décédés. Il n'y a pas de différences entre les deux groupes quant aux taux d'antigène HSP60 ou d'autres marqueurs immunologiques ou hématologiques.ConclusionLes foetus avec un RCIU inexpliqué expriment un taux élevé d'anticorps IgM et IgG contre l'HSP60 humaine et le taux d'IgM est un facteur prédictif de la mortalité foetale. La détection de ces anticorps indique qu'une perturbation placentaire et une réaction auto-immune foetale liée à l'HSP60 sont associées à ce retard de développement chez le foetus.

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Adiponectin is an adipokine, present in the circulation in comparatively high concentrations and different molecular weight isoforms. For the first time, the distribution of these isoforms in serum and follicular fluid (FF) and their usefulness as biological markers for infertility investigations was studied. In vitro study. University based hospital. Fifty-four women undergoing intracytoplasmic sperm injection (ICSI). Oocytes were retrieved, fertilized in vitro using ICSI, and the resulting embryos transferred. Serum was collected immediately prior to oocyte retrieval. Adiponectin isoforms (high molecular weight (HMW), medium and low molecular weight) were determined in serum and FF. Total adiponectin and the different isoform levels were compared with leptin and ovarian steroid concentrations. Adiponectin isoforms in serum and FF. Adiponectin isoform distribution differed between serum and FF; the HMW fraction made up half of all adiponectin in the serum but only 23.3% in the FF. Total and HMW adiponectin in both serum and FF correlated negatively with the body mass index and the concentration of leptin. No correlations were observed for total adiponectin or its isoforms with estradiol, progesterone, anti-Mullerian hormone, inhibin B, or the total follicle stimulating hormone (FSH) dose administered during the ovarian stimulation phase. This study shows for the first time that adiponectin isoform distribution varies between the serum and FF compartments in gonadotropin stimulated patients. A trend towards higher HMW adiponectin serum levels in successful ICSI cycles compared to implantation failures was observed; studies with larger patient groups are required to confirm this observation.

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L'activation des mastocytes se produit dans plusieurs conditions pathologiques et est principalement observée chez des patients développant une réaction anaphylactique. Dans la pratique clinique, la mesure de l'histamine et de ses métabolites dans le plasma et dans l'urine du patient peut être effectuée et montre parfois des résultats aussi précis que la mesure de la beta-tryptase dans le sang lorsqu'il est nécessaire de confirmer une activation mastocytaire. En revanche, la mesure de la beta tryptase dans l'urine dans un but diagnostic n'a que rarement été effectuée sur des personnes vivantes et a montré des résultats contradictoires. Dans le domaine de la médecine légale, la mesure de la beta-tryptase dans un but diagnostic est effectuée dans le sérum postmortem obtenu à partir de sang prélevé au niveau fémoral. Cependant, le sang peut être partiellement ou complètement indisponible dans certains cas spécifiques, dans les autopsies de nourrissons ou de corps sévèrement mutilés par exemple. Un des buts de notre étude est d'évaluer la pertinence de la mesure de la beta-tryptase dans des échantillons biologiques alternatifs, à savoir dans l'urine, l'humeur vitrée et le liquide péricardique. Pour cela nous avons sélectionné 94 cas d'autopsies comprenant 6 cas de réaction anaphylactique suite à l'administration de produits de contraste radiologique, 10 cas d'hypothermie, 10 cas d'acidocétose diabétique, 10 cas de suicide par arme à feu, 18 cas de décès consécutif à une injection d'héroïne, 10 cas de décès traumatiques, 10 cas de mort subite avec peu ou pas d'athérosclérose coronarienne, 10 cas de décès avec une athérosclérose coronarienne sévère mais sans signe d'infarctus du myocarde et 10 cas de décès consécutif à un infarctus du myocarde avec une athérosclérose coronarienne sévère. Dans tous les cas de réaction anaphylactique suite à l'administration de produit de contraste radiologique, les concentrations de beta-tryptase, mesurées dans le sérum postmortem et dans le liquide péricardique, ont montré des valeurs plus élevées que le seuil clinique de référence (11 ng/l) et le seuil postmortem de référence (45 ng/l). La concentration de beta-tryptase mesurée dans l'urine et l'humeur vitrée a montré des valeurs inférieures au seuil clinique dans tous les cas de notre étude. La mesure de la concentration de beta tryptase dans le liquide péricardique semble donc une alternative valable à la mesure dans le sérum postmortem, lorsque le sang fémoral n'est pas disponible durant l'autopsie, afin de poser un diagnostic de réaction anaphylactique.

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Supernatants from cell cultures (also called conditioned media, CMs) are commonly analyzed to study the pool of secreted proteins (secretome). To reduce the exogenous protein background, serum-free media are often used to obtain CMs. Serum deprivation, however, can severely affect cell viability and phenotype, including protein secretion. We present a strategy to analyze the proteins secreted by cells in fetal bovine serum-containing CMs, which combines the advantage of metabolic labeling and protein concentration linearization techniques. Incubation of CMs with a hexapeptide ligand library was used to reduce the dynamic range of the samples and led to the identification of 3 times more proteins than in untreated CM samples. Labeling with a deuterated amino acid was used to distinguish between cellular proteins and homologous bovine proteins contained in the medium. Application of the strategy to two breast cancer cell lines led to the identification of proteins secreted in different amounts and which could correlate with their varying degree of aggressiveness. Selected reaction monitoring (SRM)-based quantitation of three proteins of interest in the crude samples yielded data in good agreement with the results from concentration-equalized samples.

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Background/Purpose: Denosumab (DMAb) is an approved therapy for the treatment of postmenopausal women with osteoporosis at increased risk for fracture. A favorable risk/benefit profile was demonstrated in the pivotal, 3-year FREEDOM trial (Cummings et al NEJM 2009). The open-label, active-treatment FREEDOM Extension study is investigating the efficacy and safety of DMAb for up to 10 years. The Extension trial enrolled women who had received DMAb or placebo in FREEDOM and provides an opportunity to evaluate the long-term efficacy and safety of continuous DMAb treatment (long-term group), and to replicate the DMAb findings observed in FREEDOM (cross-over group). Here, we report the results from the first 3 years of the Extension, representing up to 6 continuous years of DMAb exposure. Methods: During the Extension, each woman is scheduled to receive 60 mg DMAb every 6 months and supplemental calcium and vitamin D daily. For the analyses reported here, women from the FREEDOM DMAb group received 3 more years of DMAb for a total of 6 years of exposure (long-term group) and women from the FREEDOM placebo group received 3 years of DMAb exposure (cross-over group). Results: Of the 5928 women eligible for the Extension, 4550 (77%) enrolled (N_2343 long-term; N_2207 cross-over). In the long-term group, further significant mean increases in bone mineral density (BMD) occurred 4044 for cumulative 6-year gains of 15.2% at the lumbar spine and 7.5% at the total hip (Figure). During the first 3 years of DMAb treatment during the Extension, the cross-over group had significant mean gains in BMD at the lumbar spine (9.4%) and total hip (4.8%), similar to those observed in the long-term DMAb group during the first 3 years of FREEDOM (lumbar spine, 10.1%; total hip, 5.7%). Serum CTX was rapidly and similarly reduced after the 1st (cross-over) or 7th (long-term) DMAb dose with the characteristic attenuation observed at the end of the dosing period. In the cross-over group, yearly incidences of new vertebral and nonvertebral fractures were lower than in the FREEDOM placebo group. Fracture incidence remained low in the long-term group. Incidences of adverse events (AEs) and serious AEs did not increase over time with DMAb treatment. There were 2 subjects with AEs adjudicated to ONJ in the cross-over group and 2 in the long-term group. Both cases in the cross-over group healed completely and without further complications; 1 of these subjects continues to receive DMAb. Both women in the long-term group continue to be followed. No atypical femur fractures have been observed to date. Figure. Percent changes in bone mineral density during FREEDOM and the Extension Conclusion: DMAb treatment for 6 continuous years (long-term group) remained well tolerated, maintained reduced bone turnover, and continued to significantly increase BMD. Fracture incidence remained low. DMAb treatment for 3 years in the cross-over group reproduced the original observations in FREEDOM

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BACKGROUND: The prevalence of hyperuricemia has rarely been investigated in developing countries. The purpose of the present study was to investigate the prevalence of hyperuricemia and the association between uric acid levels and the various cardiovascular risk factors in a developing country with high average blood pressures (the Seychelles, Indian Ocean, population mainly of African origin). METHODS: This cross-sectional health examination survey was based on a population random sample from the Seychelles. It included 1011 subjects aged 25 to 64 years. Blood pressure (BP), body mass index (BMI), waist circumference, waist-to-hip ratio, total and HDL cholesterol, serum triglycerides and serum uric acid were measured. Data were analyzed using scatterplot smoothing techniques and gender-specific linear regression models. RESULTS: The prevalence of a serum uric acid level >420 micromol/L in men was 35.2% and the prevalence of a serum uric acid level >360 micromol/L was 8.7% in women. Serum uric acid was strongly related to serum triglycerides in men as well as in women (r = 0.73 in men and r = 0.59 in women, p < 0.001). Uric acid levels were also significantly associated but to a lesser degree with age, BMI, blood pressure, alcohol and the use of antihypertensive therapy. In a regression model, triglycerides, age, BMI, antihypertensive therapy and alcohol consumption accounted for about 50% (R2) of the serum uric acid variations in men as well as in women. CONCLUSIONS: This study shows that the prevalence of hyperuricemia can be high in a developing country such as the Seychelles. Besides alcohol consumption and the use of antihypertensive therapy, mainly diuretics, serum uric acid is markedly associated with parameters of the metabolic syndrome, in particular serum triglycerides. Considering the growing incidence of obesity and metabolic syndrome worldwide and the potential link between hyperuricemia and cardiovascular complications, more emphasis should be put on the evolving prevalence of hyperuricemia in developing countries.

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Anabolic androgenic steroids (AAS) are doping agents that are mostly used for improvement of strength and muscle hypertrophy. In some sports, athletes reported that the intake of AAS is associated with a better recovery, a higher training load capacity and therefore an increase in physical and mental performances. The purpose of this study was to evaluate, the effect of multiple doses of AAS on different physiological parameters that could indirectly relate the physical state of athletes during a hard endurance training program. In a double blind settings, three groups (n = 9, 8 and 8) were orally administered placebo, testosterone undecanoate or 19-norandrostenedione, 12 times during 1 month. Serum biomarkers (creatine kinase, ASAT and urea), serum hormone profiles (testosterone, cortisol and LH) and urinary catecholamines (noradrenalin, adrenalin and dopamine) were evaluated during the treatment. Running performance was assessed before and after the intervention phase by means of a standardized treadmill test. None of the measured biochemical variables showed significant impact of AAS on physical stress level. Data from exercise testing on submaximal and maximal level did not reveal any performance differences between the three groups or their response to the treatment. In the present study, no effect of multiple oral doses of AAS on endurance performance or bioserum recovery markers was found.

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BACKGROUND: MYCN oncogene amplification has been defined as the most important prognostic factor for neuroblastoma (NB), the most common solid extracranial neoplasm in children. High copy numbers are strongly associated with rapid tumor progression and poor outcome, independently of tumor stage or patient age, and this has become an important factor in treatment stratification. PROCEDURE: By real-time quantitative PCR analysis, we evaluated the clinical relevance of circulating MYCN DNA of 267 patients with locoregional or metastatic NB in children less than 18 months of age. RESULTS: For patients in this age group with INSS stage 4 or 4S NB and stage 3 patients, serum-based determination of MYCN DNA sequences had good sensitivity (85%, 83%, and 75% respectively) and high specificity (100%) when compared to direct tumor gene determination. In contrast, the approach showed low sensitivity patients with stages 1 and 2 disease. CONCLUSION: Our results show that the sensitivity of the serum-based MYCN DNA sequence determination depends on the stage of the disease. However, this simple, reproducible assay may represent a reasonably sensitive and very specific tool to assess tumor MYCN status in cases with stage 3 and metastatic disease for whom a wait and see strategy is often recommended.

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BACKGROUND: Renal calcium stones and hypercalciuria are associated with a reduced bone mineral density (BMD). Therefore, the effect of changes in calcium homeostasis is of interest for both stones and bones. We hypothesized that the response of calciuria, parathyroid hormone (PTH) and 1.25 vitamin D to changes in dietary calcium might be related to BMD. METHODS: A single-centre prospective interventional study of 94 hyper- and non-hypercalciuric calcium stone formers consecutively retrieved from our stone clinic. The patients were investigated on a free-choice diet, a low-calcium diet, while fasting and after an oral calcium load. Patient groups were defined according to lumbar BMD (z-score) obtained by dual X-ray absorptiometry (group 1: z-score <-0.5, n = 30; group 2: z-score -0.5-0.5, n = 36; group 3: z-score >0.5, n = 28). The effect of the dietary interventions on calciuria, 1.25 vitamin D and PTH in relation to BMD was measured. RESULTS: An inverse relationship between BMD and calciuria was observed on all four calcium intakes (P = 0.009). On a free-choice diet, 1.25 vitamin D and PTH levels were identical in the three patient groups. However, the relative responses of 1.25 vitamin D and PTH to the low-calcium diet were opposite in the three groups with the highest increase of 1.25 vitamin D in group 1 and the lowest in group 3, whereas PTH increase was most pronounced in group 3 and least in group 1. CONCLUSION: Calcium stone formers with a low lumbar BMD exhibit a blunted response of PTH release and an apparently overshooting production of 1.25 vitamin D following a low-calcium diet.

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BACKGROUND: The relation of serum uric acid (SUA) with systemic inflammation has been little explored in humans and results have been inconsistent. We analyzed the association between SUA and circulating levels of interleukin-6 (IL-6), interleukin-1beta (IL-1beta), tumor necrosis factor- alpha (TNF-alpha) and C-reactive protein (CRP). METHODS AND FINDINGS: This cross-sectional population-based study conducted in Lausanne, Switzerland, included 6085 participants aged 35 to 75 years. SUA was measured using uricase-PAP method. Plasma TNF-alpha, IL-1beta and IL-6 were measured by a multiplexed particle-based flow cytometric assay and hs-CRP by an immunometric assay. The median levels of SUA, IL-6, TNF-alpha, CRP and IL-1beta were 355 micromol/L, 1.46 pg/mL, 3.04 pg/mL, 1.2 mg/L and 0.34 pg/mL in men and 262 micromol/L, 1.21 pg/mL, 2.74 pg/mL, 1.3 mg/L and 0.45 pg/mL in women, respectively. SUA correlated positively with IL-6, TNF-alpha and CRP and negatively with IL-1beta (Spearman r: 0.04, 0.07, 0.20 and 0.05 in men, and 0.09, 0.13, 0.30 and 0.07 in women, respectively, P<0.05). In multivariable analyses, SUA was associated positively with CRP (beta coefficient +/- SE = 0.35+/-0.02, P<0.001), TNF-alpha (0.08+/-0.02, P<0.001) and IL-6 (0.10+/-0.03, P<0.001), and negatively with IL-1beta (-0.07+/-0.03, P = 0.027). Upon further adjustment for body mass index, these associations were substantially attenuated. CONCLUSIONS: SUA was associated positively with IL-6, CRP and TNF-alpha and negatively with IL-1beta, particularly in women. These results suggest that uric acid contributes to systemic inflammation in humans and are in line with experimental data showing that uric acid triggers sterile inflammation.

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BACKGROUND: In a previous study we demonstrated that mild metabolic alkalosis resulting from standard bicarbonate haemodialysis induces hypotension. In this study, we have further investigated the changes in systemic haemodynamics induced by bicarbonate and calcium, using non-invasive procedures. METHODS: In a randomized controlled trial with a single-blind, crossover design, we sequentially changed the dialysate bicarbonate and calcium concentrations (between 26 and 35 mmol/l for bicarbonate and either 1.25 or 1.50 mmol/l for calcium). Twenty-one patients were enrolled for a total of 756 dialysis sessions. Systemic haemodynamics was evaluated using pulse wave analysers. Bioimpedance and BNP were used to compare the fluid status pattern. RESULTS: The haemodynamic parameters and the pre-dialysis BNP using either a high calcium or bicarbonate concentration were as follows: systolic blood pressure (+5.6 and -4.7 mmHg; P < 0.05 for both), stroke volume (+12.3 and +5.2 ml; P < 0.05 and ns), peripheral resistances (-190 and -171 dyne s cm(-5); P < 0.05 for both), central augmentation index (+1.1% and -2.9%; ns and P < 0.05) and BNP (-5 and -170 ng/l; ns and P < 0.05). The need of staff intervention was similar in all modalities. CONCLUSIONS: Both high bicarbonate and calcium concentrations in the dialysate improve the haemodynamic pattern during dialysis. Bicarbonate reduces arterial stiffness and ameliorates the heart tolerance for volume overload in the interdialytic phase, whereas calcium directly increases stroke volume. The slight hypotensive effect of alkalaemia should motivate a probative reduction of bicarbonate concentration in dialysis fluid for haemodynamic reasons, only in the event of failure of classical tools to prevent intradialytic hypotension.

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Few data for normal urinary oxalate (Ox) and calcium (Ca) excretion related both to gestational age and nutritional factors have been reported in preterm or term infants. We therefore determined the molar Ox and Ca to creatinine (Cr) ratios in spot urines from 64 preterm and 37 term infants aged 1-60 days, either fed formula or human milk (HM). Only vitamin D was supplemented; renal or metabolic diseases were excluded. Urinary Ox/Cr ratio was higher in preterm than in term infants, both when formula fed (1st month 253 vs. 180 mmol/mol and 2nd month 306 vs. 212 mmol/mol; P&lt;0.05) or HM fed (206 vs. 169 mmol/ mol and 283* vs. 232 mmol/mol; *P&lt;0.05). Ox/Cr was also higher in formula- than HM-fed preterm infants. The ratio increased during the first 2 months of life irrespective of nutrition. Urinary Ca/Cr ratio was comparable in all groups during the 1st month of life, except for a lower (P &lt; 0.05) value in term infants fed HM (0.10 mol/mol). It increased in all groups during the 2nd month of life, being highest in HM-fed preterm infants (1.86 mol/mol). In conclusion, urinary Ox and Ca excretion is influenced by both gestational age and nutrient intake in preterm and term infants.

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The involvement of voltage-gated calcium channels in the survival of immature CNS neurons was studied in aggregating brain cell cultures by examining cell type-specific effects of various channel blockers. Nifedipine (10 microM), a specific blocker of L-type calcium channels, caused a pronounced and irreversible decrease of glutamic acid decarboxylase activity, whereas the activity of choline acetyltransferase was significantly less affected. Flunarizine (1-10 microM, a relatively unspecific ion channel blocker) elicited similar effects, that were attenuated by NMDA. The glia-specific marker enzymes, glutamine synthetase and 2',3'-cyclic nucleotide 3'-phosphohydrolase, were affected only after treatment with high concentrations of nifedipine (50 microM) or NiCl2 (100 microM, shown to block T-type calcium channels). Nifedipine (50 microM), NiCl2 (100 microM), and flunarizine (5 microM) also caused a significant increase in the soluble nucleosome concentration, indicating increased apoptotic cell death. This effect was prevented by cycloheximide (1 microM). Furthermore, the combined treatment with calcicludine (10 nM, blocking L-type calcium channels) and funnel-web spider toxin-3.3 (100 nM, blocking T-type channels) also caused a significant increase in free nucleosomes as well as a decrease in glutamic acid decarboxylase activity. In contrast, cell viability was not affected by peptide blockers specific for N-, P-, and/or Q-type calcium channels. Highly differentiated cultures showed diminished susceptibility to nifedipine and flunarizine. The present data suggest that the survival of immature neurons, and particularly that of immature GABAergic neurons, requires the sustained entry of Ca2+ through voltage-gated calcium channels.

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Alleviation of Al rhizotoxicity by Ca and Mg can differ among species and genotypes. Root elongation of soybean [Glycine max (L.) Merr.] line N93-S-179 and cvs. Young and Ransom exposed to varying concentrations of Al, Ca and Mg were compared in two experiments using a vertically split root system. Roots extending from a surface compartment with limed soil grew for 12 days into a subsurface compartment with nutrient solution treatments maintained at pH 4.6 with either 0 or 15 µmol L-1 Al. Calcium and Mg concentrations in treatments ranging from 0 to 20 mmol L-1. Although an adequate supply of Mg was provided in the surface soil compartment for soybean top growth, an inclusion of Mg was necessary in the subsurface solutions to promote root elongation in both the presence and absence of Al. In the absence of Al in the subsurface solution, tap root length increased by 74 % and lateral root length tripled when Mg in the solutions was increased from 0 to either 2 or 10 mmol L-1. In the presence of 15 µmol L-1 Al, additions of 2 or 10 mmol L-1 Mg increased tap root length fourfold and lateral root length by a factor of 65. This high efficacy of Mg may have masked differences in Al tolerance between genotypes N93 and Young. Magnesium was more effective than Ca in alleviating Al rhizotoxicity, and its ameliorative properties could not be accounted for by estimated electrostatic changes in root membrane potential and Al3+ activity at the root surface. The physiological mechanisms of Mg alleviation of Al injury in roots, however, are not known.