982 resultados para Wave Run-up


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Purpose: To study with a non invasive method any potential radiological change on the superior cerebellar artery (SCA) in patients treated radiosurgically for classic trigeminal neuralgia (CTN).Materials and methods: A retrospective measure of maximal dose received by SCA was performed analyzing the treatment planning in 55 consecutive patients treated by Gamma Knife radiosurgery for an CTN, then, a prospective study was designed using high resolution MR, with T2 SPIR, T1 without and with gadolinium enhancement, Proton density, 3D TONE and MIP reconstructions. Inclusion criteria were: patients followed at our institution, follow-up of one year or more, dose received by the SCA of 15 Gy or more and voluntary patient participation in the study. Patients with repeated Gamma Knife radiosurgery for failure or recurrence were excluded. The end points were: SCA occlusion, stenosis or infarction in the territory supplied by SCA.Results: Sixteen patients were studied, with a mean follow-up of 25.2 months (12-42 months). The mean maximal dose received by the SCA was 57.5 Gy. (15-87 Gy). Among these 16 patients studied, neither obstruction of the SCA nor infarction was demonstrated. In one patient a suspicion of asymptomatic SCA stenosis was visualized distant to the irradiation field.Conclusions: SCA can receive a high dose of irradiation during radiosurgical treatment for CTN. This study does not confirm any vascular damage to the SCA after radiosurgery for CTN. (C) 2011 Elsevier B.V. All rights reserved.

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Leptin, the 16,000 molecular weight protein product of the obese gene, was originally considered as an adipocyte-derived signaling molecule for the central control of metabolism. However, leptin has been suggested to be involved in other functions during pregnancy, particularly in placenta, in which it was found to be expressed. In the present work, we have found that recombinant human chorionic gonadotropin (hCG) added to BeWo choriocarcinoma cell line showed a stimulatory effect on endogenous leptin expression, when analyzed by Western blot. This effect was time and dose dependent. Maximal effect was achieved at hCG 100 IU/ml. Moreover, hCG treatment enhanced leptin promoter activity up to 12.9 times, evaluated by transient transfection with a plasmid construction containing different promoter regions and the reporter gene luciferase. This effect was dose dependent and evidenced with all the promoter regions analyzed, regardless of length. Similar results were obtained with placental explants, thus indicating physiological relevance. Because hCG signal transduction usually involves cAMP signaling, this pathway was analyzed. Contrarily, we found that dibutyryl cAMP counteracted hCG effect on leptin expression. Furthermore, cotransfection with the catalytic subunit of PKA and/or the transcription factor cAMP response element binding protein repressed leptin expression. Thereafter we determined that hCG effect could be partially blocked by pharmacologic inhibition of MAPK pathway with 50 microM PD98059 but not by the inhibition of the phosphatidylinositol 3-kinase pathway with 0.1 microm wortmannin. Moreover, hCG treatment promoted MAPK kinase and ERK1/ERK2 phosphorylation in placental cells. Finally, cotransfection with a dominant-negative mutant of MAPK blocked the hCG-mediated activation of leptin expression. In conclusion, we provide some evidence suggesting that hCG induces leptin expression in trophoblastic cells probably involving the MAPK signal transduction pathway.

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Glucose control is the cornerstone of Diabetes Mellitus (DM) treatment. Although self-regulation using capillary glycemia (SRCG) still remains the best procedure in clinical practice, continuous glucose monitoring systems (CGM) offer the possibility of continuous and dynamic assessment of interstitial glucose concentration. CGM systems have the potential to improve glycemic control while decreasing the incidence of hypoglycemia but the efficiency, compared with SRCG, is still debated. CGM systems have the greatest potential value in patients with hypoglycemic unawareness and in controlling daily fluctuations in blood glucose. The implementation of continuous monitoring in the standard clinical setting has not yet been established but a new generation of open and close loop subcutaneous insulin infusion devices are emerging making insulin treatment and glycemic control more reliable.

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This study examined the validity and reliability of a sequential "Run-Bike-Run" test (RBR) in age-group triathletes. Eight Olympic distance (OD) specialists (age 30.0 ± 2.0 years, mass 75.6 ± 1.6 kg, run VO2max 63.8 ± 1.9 ml· kg(-1)· min(-1), cycle VO2peak 56.7 ± 5.1 ml· kg(-1)· min(-1)) performed four trials over 10 days. Trial 1 (TRVO2max) was an incremental treadmill running test. Trials 2 and 3 (RBR1 and RBR2) involved: 1) a 7-min run at 15 km· h(-1) (R1) plus a 1-min transition to 2) cycling to fatigue (2 W· kg(-1) body mass then 30 W each 3 min); 3) 10-min cycling at 3 W· kg(-1) (Bsubmax); another 1-min transition and 4) a second 7-min run at 15 km· h(-1) (R2). Trial 4 (TT) was a 30-min cycle - 20-min run time trial. No significant differences in absolute oxygen uptake (VO2), heart rate (HR), or blood lactate concentration ([BLA]) were evidenced between RBR1 and RBR2. For all measured physiological variables, the limits of agreement were similar, and the mean differences were physiologically unimportant, between trials. Low levels of test-retest error (i.e. ICC <0.8, CV<10%) were observed for most (logged) measurements. However [BLA] post R1 (ICC 0.87, CV 25.1%), [BLA] post Bsubmax (ICC 0.99, CV 16.31) and [BLA] post R2 (ICC 0.51, CV 22.9%) were least reliable. These error ranges may help coaches detect real changes in training status over time. Moreover, RBR test variables can be used to predict discipline specific and overall TT performance. Cycle VO2peak, cycle peak power output, and the change between R1 and R2 (deltaR1R2) in [BLA] were most highly related to overall TT distance (r = 0.89, p < 0. 01; r = 0.94, p < 0.02; r = 0.86, p < 0.05, respectively). The percentage of TR VO2max at 15 km· h(-1), and deltaR1R2 HR, were also related to run TT distance (r = -0.83 and 0.86, both p < 0.05).

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BACKGROUND Antiretroviral treatment (ART) in children has special features and consequently, results obtained from clinical trials with antiretroviral drugs in adults may not be representative of children. Nelfinavir (NFV) is an HIV-1 Protease Inhibitor (PI) which has become as one of the first choices of PI for ART in children. We studied during a 3-year follow-up period the effects of highly active antiretroviral therapy with nelfinavir in vertically HIV-1 infected children. METHODS Forty-two vertically HIV-infected children on HAART with NFV were involved in a multicentre prospective study. The children were monitored at least every 3 months with physical examinations, and blood sample collection to measure viral load (VL) and CD4+ cell count. We performed a logistic regression analysis to determinate the odds ratio of baseline characteristics on therapeutic failure. RESULTS Very important increase in CD4+ was observed and VL decreased quickly and it remained low during the follow-up study. Children with CD4+ <25% at baseline achieved CD4+ >25% at 9 months of follow-up. HIV-infected children who achieved undetectable viral load (uVL) were less than 40% in each visit during follow-up. Nevertheless, HIV-infected children with VL >5000 copies/ml were less than 50% during the follow-up study. Only baseline VL was an important factor to predict VL control during follow-up. Virological failure at defined end-point was confirmed in 30/42 patients. Along the whole of follow-up, 16/42 children stopped HAART with NFV. Baseline characteristics were not associated with therapeutic change. CONCLUSION NFV is a safe drug with a good profile and able to achieve an adequate response in children.

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Introduction: Two subcutaneous injections of adalimumab in severeacute sciatica have demonstrated a significant benefit on the numberof back surgeries in a short-term randomized controlled clinical trial[1]. This 3-year follow-up study aimed to determine whether theshort-term benefit was sustained over a longer period of time.Methods: Information on surgery was retrieved in 56/61 patients(93%). We used a Cox proportional hazard models to determinefactors predisposing to surgery.Results: Twenty-three (41%) patients had back surgery within 3 years,8/29 (28%) in the adalimumab group and 15/ 27 (56%) in the placebogroup, p = 0.038. Adalimumab injections reduced the need for backsurgery by 61% (Hazard Ratio (HR): 0.39 (95% CI: 0.17-0.92). In amultivariate model, treatment with a TNF-α antagonist remained thestrongest protective factor (HR 0.17, p = 0.002). Other significantpredictors of surgery were a good correlation between symptomsand MRI findings (HR = 11.6, p = 0.04), baseline intensity of leg pain(HR = 1.3, p = 0.06), intensity of back pain (HR = 1.4, p = 0.03)and duration of sickness leave (HR = 1.01 per day, p = 0.03).Conclusion: A short course of adalimumab in patients with severeacute sciatica significantly reduces the need for back surgery.

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Background: In FL, Rituximab as a single agent delivered in the standard schedule (4 times weekly) may induce a response rate of 50−70% with an event-free survival (EFS) of 1−3 years according to patients' characteristics. Prolonged Rituximab exposure seems to improve EFS at least in responding patients and to increase the rate of longterm responders. Here we report long-term results of a clinical trial comparing single agent Rituximab delivered in the standard schedule versus prolonged exposure, with focus on the proportion of long-term responders and their characteristics. Material and Methods: Between 1998 and 2002, chemotherapy na¨ıve (n = 64) or pre-treated (n = 138) FL patients received Rituximab in the standard schedule. Those responding or with stable disease were randomized to no further treatment (observation, n = 78) or 4 additional doses of Rituximab given at 2-month intervals (prolonged exposure, n = 73). EFS was calculated from the first dose of standard schedule until progression, relapse, second tumor or death. Results: At a median follow up of 9.4 years and with all living patients having been followed for at least 5 years, the median EFS is 13 months for the observation and 24 months for the prolonged exposure arm (p = 0.0007). In the observation arm 13% had no event at 5-years and only 4% at 8 years, while in the prolonged exposure arm it was 27% at 5 years and remained 21% at 8 years. The only significant prognostic factor for EFS in a multivariate Cox regression was the prolonged Rituximab schedule (hazard ratio 0.58, CI 0.39−0.86, p = 0.007), whereas being chemotherapy na¨ıve, presenting with stage

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Background: Several markers of atherosclerosis and of inflammation have been shown to predict coronary heart disease (CHD) individually. However, the utility of markers of atherosclerosis and of inflammation on prediction of CHD over traditional risk factors has not been well established, especially in the elderly. Methods: We studied 2202 men and women, aged 70-79, without baseline cardiovascular disease over 6-year follow-up to assess the risk of incident CHD associated with baseline noninvasive measures of atherosclerosis (ankle-arm index [AAI], aortic pulse wave velocity [aPWV]) and inflammatory markers (interleukin-6 [IL-6], C-reactive protein [CRP], tumor necrosis factor-a [TNF-a]). CHD events were studied as either nonfatal myocardial infarction or coronary death ("hard" events), and "hard" events plus hospitalization for angina, or the need for coronary-revascularization procedures (total CHD events). Results: During the 6-year follow-up, 283 participants had CHD events (including 136 "hard" events). IL-6, TNF-a and AAI independently predicted CHD events above Framingham Risk Score (FRS) with hazard ratios [HR] for the highest as compared with the lowest quartile for IL-6 of 1.95 (95%CI: 1.38-2.75, p for trend <0.001), TNF-a of 1.45 (95%CI: 1.04-2.02, p for trend 0.03), of 1.66 (95%CI: 1.19-2.31) for AAI 0.9, as compared to AAI 1.01-1.30. CRP and aPWV were not independently associated with CHD events. Results were similar for "hard" CHD events. Addition of IL-6 and AAI to traditional cardiovascular risk factors yielded the greatest improvement in the prediction of CHD; C-index for "hard"/total CHD events increased from 0.62/0.62 for traditional risk factors to 0.64/0.64 for IL-6 addition, 0.65/0.63 for AAI, and 0.66/0.64 for IL-6 combined with AAI. Being in the highest quartile of IL-6 combined with an AAI 0.90 or >1.40 yielded an HR of 2.51 (1.50-4.19) and 4.55 (1.65-12.50) above FRS, respectively. With use of CHD risk categories, risk prediction at 5 years was more accurate in models that included IL-6, AAI or both, with 8.0, 8.3 and 12.1% correctly reclassified, respectively. Conclusions: Among older adults, markers of atherosclerosis and of inflammation, particularly IL-6 and AAI, are independently associated with CHD. However, these markers only modestly improve cardiovascular risk prediction beyond traditional risk factors.

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Glucocorticoids reduce diabetic macular edema, but the mechanisms underlying glucocorticoid effects are imperfectly elucidated. Glucocorticoids may bind to glucocorticoid (GR) and mineralocorticoid (MR) receptors. We hypothesize that MR activation may influence retinal hydration. The effect of the MR agonist aldosterone (24 h) on ion/water channel expression (real-time PCR, Western blot, immunofluorescence) was investigated on cultured retinal Müller glial cells (RMGs, which contribute to fluid homeostasis in the retina), in Lewis rat retinal explants, and in retinas from aldosterone-injected eyes. We evidenced cell-specific expression of MR, GR, and 11-beta-hydroxysteroid dehydrogenase type II. Aldosterone significantly enhances expression of sodium and potassium channels ENaC-alpha (6.5-fold) and Kir4.1 (1.9-fold) through MR and GR occupancy, whereas aquaporin 4 (AQP4, 2.9-fold) up-regulation is MR-selective. Aldosterone intravitreous injection induces retinal swelling (24% increase compared to sham-injected eyes) and activation of RMGs. It promotes additional localization of Kir4.1 and AQP4 toward apical microvilli of RMGs. Our results highlight the mineralocorticoid-sensitivity of the neuroretina and show that aldosterone controls hydration of the healthy retina through regulation of ion/water channels expression in RMGs. These results provide a rationale for future investigations of abnormal MR signaling in the pathological retina.

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CONTEXT GH treatment is effective in children born small for gestational age (SGA); however, its effectiveness and safety in very young SGA children is unknown. OBJECTIVE The aim was to analyze the outcome of very young SGA children treated with GH and followed for 2 yr. The results after 24 months of treatment, compared with a control group without treatment during 12 months followed by 12 months of treatment, are shown. DESIGN We performed a multicenter, controlled, randomized, open trial. SETTINGS The pediatric endocrinology departments of 14 public hospitals in Spain participated in the study. PATIENTS Seventy-six children, aged 2-5 yr born SGA and without catch-up growth, were studied. INTERVENTION Children received GH at 0.06 mg/kg.d for 2 yr (group I) or were followed for 12 months with no treatment and then treated for 12 months (group II). MAIN OUTCOME MEASURES Age, general health status, pubertal stage, bone age, height, weight, biochemical and hormonal analyses, and adverse side effects were determined at biannual check-ups. RESULTS The mean height sd score gain for chronological age in children treated for 24 months (group I) was 2.10, whereas in those treated only during the last 12 months (group II) was 1.43. In both groups, children under 4 yr of age had the greatest gain in growth velocity. No significant acceleration of bone age or side effects related to treatment was seen. CONCLUSION Very young SGA children without spontaneous catch-up growth could benefit from GH treatment because growth was accelerated and no negative side effects were observed.

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Introduction: Ethylglucuronide (EtG) is a direct and specific metabolite of ethanol. Its determination in hair is of increasing interest for detecting and monitoring alcohol abuse. The quantification of EtG in hair requires analytical methods showing highest sensitivity and specificity. We present a fully validated method based on gas chromatography-negative chemical ionization tandem mass spectrometry (GC-NCI-MS/MS). The method was validated using French Society of Pharmaceutical Sciences and Techniques (SFSTP) guidelines which are based on the determination of the total measurement error and accuracy profiles. Methods: Washed and powdered hair is extracted in water using an ultrasonic incubation. After purification by Oasis MAX solid phase extraction, the derivatized EtG is detected and quantified by GC-NCI-MS/MS method in the selected reaction monitoring mode. The transitions m/z 347 / 163 and m/z 347 / 119 were used for the quantification and identification of EtG. Four quality controls (QC) prepared with hair samples taken post mortem from 2 subjects with a known history of alcoholism were used. A proficiency test with 7 participating laboratories was first run to validate the EtG concentration of each QC sample. Considering the results of this test, these samples were then used as internal controls for validation of the method. Results: The mean EtG concentrations measured in the 4 QC were 259.4, 130.4, 40.8, and 8.4 pg/mg hair. Method validation has shown linearity between 8.4 and 259.4 pg/mg hair (r2 > 0.999). The lower limit of quantification was set up at 8.4 pg/mg. Repeatability and intermediate precision were found less than 13.2% for all concentrations tested. Conclusion: The method proved to be suitable for routine analysis of EtG in hair. GC-NCI-MS/MS method was then successfully applied to the analysis of EtG in hair samples collected from different alcohol consumers.

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CONTEXT Adipose tissue hypoxia and endoplasmic reticulum (ER) stress may link the presence of chronic inflammation and macrophage infiltration in severely obese subjects. We previously reported the up-regulation of TNF-like weak inducer of apoptosis (TWEAK)/fibroblast growth factor-inducible 14 (Fn14) axis in adipose tissue of severely obese type 2 diabetic subjects. OBJECTIVES The objective of the study was to examine TWEAK and Fn14 adipose tissue expression in obesity, severe obesity, and type 2 diabetes in relation to hypoxia and ER stress. DESIGN In the obesity study, 19 lean, 28 overweight, and 15 obese nondiabetic subjects were studied. In the severe obesity study, 23 severely obese and 35 control subjects were studied. In the type 2 diabetes study, 11 type 2 diabetic and 36 control subjects were studied. The expression levels of the following genes were analyzed in paired samples of sc and visceral adipose tissue: Fn14, TWEAK, VISFATIN, HYOU1, FIAF, HIF-1a, VEGF, GLUT-1, GRP78, and XBP-1. The effect of hypoxia, inflammation, and ER stress on the expression of TWEAK and Fn14 was examined in human adipocyte and macrophage cell lines. RESULTS Up-regulation of TWEAK/Fn14 and hypoxia and ER stress surrogate gene expression was observed in sc and visceral adipose tissue only in our severely obese cohort. Hypoxia modulates TWEAK or Fn14 expression in neither adipocytes nor macrophages. On the contrary, inflammation up-regulated TWEAK in macrophages and Fn14 expression in adipocytes. Moreover, TWEAK had a proinflammatory effect in adipocytes mediated by the nuclear factor-kappaB and ERK but not JNK signaling pathways. CONCLUSIONS Our data suggest that TWEAK acts as a pro-inflammatory cytokine in the adipose tissue and that inflammation, but not hypoxia, may be behind its up-regulation in severe obesity.

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Schistosomiasis, classified by the World Health Organization as a neglected tropical disease, is an intravascular parasitic disease associated to a chronic inflammatory state. Evidence implicating inflammation in vascular dysfunction continues to mount, which, broadly defined, reflects a failure in the control of intracellular Ca2+ and consequently, vascular contraction. Therefore, we measured aorta contraction induced by 5-hydroxytryptamine (5-HT) and endothelin-1 (ET-1), two important regulators of vascular contraction. Isometric aortic contractions were determined in control and Schistosoma mansoni-infected mice. In the infected animals, 5-HT induced a 50% higher contraction in relation to controls and we also observed an increased contraction in response to Ca2+ mobilisation from sarcoplasmic reticulum. Nevertheless, Rho kinase inhibition reduced the contraction in response to 5-HT equally in both groups, discarding an increase of the contractile machinery sensitivity to Ca2+. Furthermore, no alteration was observed for contractions induced by ET-1 in both groups. Our data suggest that an immune-vascular interaction occurs in schistosomiasis, altering vascular contraction outside the mesenteric portal system. More importantly, it affects distinct intracellular signalling involved in aorta contraction, in this case increasing 5-HT receptor signalling.