Nuclear-modification factor for open-heavy-flavor production at forward rapidity in Cu plus Cu collisions at root s(NN)=200 GeV

Background: Heavy-flavor production in p + p collisions is a good test of perturbative-quantum-chromodynamics (pQCD) calculations. Modification of heavy-flavor production in heavy-ion collisions relative to binary-collision scaling from p + p results, quantified with the nuclear-modification factor (R-AA), provides information on both cold-and hot-nuclear-matter effects. Midrapidity heavy-flavor R-AA measurements at the Relativistic Heavy Ion Collider have challenged parton-energy-loss models and resulted in upper limits on the viscosity-entropy ratio that are near the quantum lower bound. Such measurements have not been made in the forward-rapidity region. Purpose: Determine transverse-momentum (p(T)) spectra and the corresponding R-AA for muons from heavy-flavor meson decay in p + p and Cu + Cu collisions at root s(NN) = 200 GeV and y = 1.65. Method: Results are obtained using the semileptonic decay of heavy-flavor mesons into negative muons. The PHENIX muon-arm spectrometers measure the p(T) spectra of inclusive muon candidates. Backgrounds, primarily due to light hadrons, are determined with a Monte Carlo calculation using a set of input hadron distributions tuned to match measured-hadron distributions in the same detector and statistically subtracted. Results: The charm-production cross section in p + p collisions at root s = 200 GeV, integrated over p(T) and in the rapidity range 1.4 < y < 1.9, is found to be d(sigma e (e) over bar)/dy = 0.139 +/- 0.029 (stat)(-0.058)(+0.051) (syst) mb. This result is consistent with a perturbative fixed-order-plus-next-to-leading-log calculation within scale uncertainties and is also consistent with expectations based on the corresponding midrapidity charm-production cross section measured by PHENIX. The R-AA for heavy-flavor muons in Cu + Cu collisions is measured in three centrality bins for 1 < p(T) < 4 GeV/c. Suppression relative to binary-collision scaling (R-AA < 1) increases with centrality. Conclusions: Within experimental and theoretical uncertainties, the measured charm yield in p + p collisions is consistent with state-of-the-art pQCD calculations. Suppression in central Cu + Cu collisions suggests the presence of significant cold-nuclear-matter effects and final-state energy loss.

Evaluation of frozen-section analysis of surgical margins in the treatment of breast cancer

Objective: To evaluate surgical margins in cases of ductal carcinoma through a histopathological exam using frozen sections. Materials and Methods: Retrospective study encompassing 242 conservative surgeries, 179 of which included intraoperative frozensection histopathology and 63 intraoperative nonfreezing techniques (macroscopy/gross examination and cytology). The results of such analyses were compared with those of the histology processing following paraffin embedment and hematoxylin and eosin (H & E) staining. A margin was deemed free when the distance between the tumor and the surgical border was equal to or greater than two millimeters. The factors given consideration for possibly affecting the results were: age, surgical aspects (skin removal and widening of surgical margins), histopathological findings (size, affected lymph nodes, and angiolymphatic invasion), and extensive intraductal and immunohistochemical components (estrogen, progesterone, Ki-67, and HER-2 receptors). In the statistical analyses, the chi-square test was used and negative predictive values were calculated. Results: The negative predictive values were 87.1% and 79.3% for frozen and nonfrozen sections, respectively. There was no significant difference between the two groups (p = 0.14). The factors under consideration had no influence on the results of the intraoperative exam of the margins. Conclusion: The present study allowed to conclude that the intraoperative exam of the surgical margins by frozen section is not superior to a macroscopy and / or cytology exam.

Hybrid Scaffolds Built From PET and Collagen as a Model For Vascular Graft Architecture

A hybrid material with excellent mechanical and biological properties is produced by electrospinning a co-solution of PET and collagen. The fibers are mapped using SEM, confocal Raman microscopy and collagenase digestion assays. Fibers of different compositions and morphologies are intermingled within the same membrane, resulting in a heterogeneous scaffold. The collagen distribution and exposure are found to depend on the PET/collagen ratio. The materials are chemically and mechanically characterized and biologically tested with fibroblasts (3T3-L1) and a HUVEC culture in vitro. All of the hybrid scaffolds show better cell attachment and proliferation than PET. These materials are potential candidates to be used as vascular grafts.

Differences in early biomechanical properties after myopic and hyperopic lasik using mechanical microkeratome Sub-Bowman's Keratomileusis (SBK)

Purpose: To evaluate biomechanical changes measured with the ORA (Ocular Response Analyzer (R); Reichert Ophthalmic Instruments, Buffalo, New York, USA) after Lasik with the Moria One Use Plus and to compare the biomechanics changes after myopic and hyperopic ablations. Methods: Fourteeneyes for hyperopia (H) and 19 eyes for myopia (M) were evaluated with the ORA preoperatively and 1 month after Lasik with thin flap (100 microns) using SBK-OUP (Sub-Bowman Keratomileusis-One Use Plus, Moria (R)). CH (Corneal Hysteresis), CRF (Corneal Resistance Factor), IOPg (gold-standard, Goldmann correlated Intraocular pressure), IOPcc (Corneal compensated Intraocular pressure) and more 38 variables derived from the corneal biomechanical response signal of the ORA were analyzed. The Wilcoxon test was used to assess differences between the variables before and after surgery for each group and the differences between the pre and postoperative (1 month) myopic eyes were compared with those obtained in hyperopic eyes, using the Mann-Whitney test. Results: There was a significant difference before and after Lasik in myopic and hyperopic eyes in IOPg (Wilcoxon, p<0.05), but not in IOPcc. Only myopic eyes showed a significant difference in CH and CRF measurements before and after LASIK, as well as 9 other biomechanical parameters (aspect1, h1, dive1, path1, p1area1, W11, H11, and w2 path11; Wilcoxon, p<0, 05), 8 of these being related to the first sign of flattening. Five parameters related to the sign of the second applanation showed significant variation only in the eyes before and after hyperopic Lasik (aspect2, h2, dive2, mslew2 and H21; Wilcoxon, p<0,05). There was a difference in both myopic and hyperopic on three parameters related to the applanation signal areas (p1area, and p2area p2area1; Wilcoxon, p<0.05). Differences in IOPg and p1area, before and after surgery were significantly higher in myopic eyes than in hyperopic eyes (Mann-Whitey, p<0.05). Conclusion: There are several significant differences in biomechanical parameters after Lasik with Moria OUP_SBK. Overall, the impact of myopic LASIK on corneal biomechanics is higher than of hyperopic Lasik. The parameters derived from the first sign of the ORA are more affected in myopic LASIK, whereas parameters derived from the second applanation are more affected in hyperopic LASIK.

Effect of continuous and interval exercise training on the PETCO2 response during a graded exercise test in patients with coronary artery disease

OBJECTIVE: The purpose of this study was to evaluate the following: 1) the effects of continuous exercise training and interval exercise training on the end-tidal carbon dioxide pressure (PETCO2) response during a graded exercise test in patients with coronary artery disease; and 2) the effects of exercise training modalities on the association between PETCO2 at the ventilatory anaerobic threshold (VAT) and indicators of ventilatory efficiency and cardiorespiratory fitness in patients with coronary artery disease. METHODS: Thirty-seven patients (59.7 +/- 1.7 years) with coronary artery disease were randomly divided into two groups: continuous exercise training (n = 20) and interval exercise training (n = 17). All patients performed a graded exercise test with respiratory gas analysis before and after three months of the exercise training program to determine the VAT, respiratory compensation point (RCP) and peak oxygen consumption. RESULTS: After the interventions, both groups exhibited increased cardiorespiratory fitness. Indeed, the continuous exercise and interval exercise training groups demonstrated increases in both ventilatory efficiency and PETCO2 values at VAT, RCP, and peak of exercise. Significant associations were observed in both groups: 1) continuous exercise training (PETCO(2)VAT and cardiorespiratory fitness r = 0.49; PETCO(2)VAT and ventilatory efficiency r = -0.80) and 2) interval exercise training (PETCO(2)VAT and cardiorespiratory fitness r = 0.39; PETCO(2)VAT and ventilatory efficiency r = -0.45). CONCLUSIONS: Both exercise training modalities showed similar increases in PETCO2 levels during a graded exercise test in patients with coronary artery disease, which may be associated with an improvement in ventilatory efficiency and cardiorespiratory fitness.

Assessment of a Neurophysiological Model of the Mandibular Branch of the Facial Nerve in Rats by Electromyography

Objectives: Our objective was to develop an experimental model for the noninvasive and objective evaluation of facial nerve regeneration in rats using a motor nerve conduction test (electromyography). Methods: Twenty-two rats were submitted to neurophysiological evaluation using motor nerve conduction of the mandibular branch of the facial nerve to obtain the compound muscle action potentials (CMAPs). To record the CM APs, we used two needle electrodes that were inserted into the lower lip muscle of the rat. A supramaximal electrical stimulus was applied, and the values of CMAP latency, amplitude, length, area, and stimulus intensity obtained from each side were compared by use of the Wilcoxon test. Results: There was no significant difference (all p > 0.05) in latency, amplitude, duration, area, or intensity of stimuli between the two sides. The amplitudes ranged between 1.61 and 8.30 mV, the latencies between 1.03 and 1.97 ms, and the stimulus intensities between 1.50 and 2.90 mA. Conclusions: This is a noninvasive, easy, and highly reproducible method that contributes to an improvement of the techniques previously described and may contribute to future studies of the degeneration and regeneration of the facial nerve.

Orthorexia nervosa behavior in a sample of Brazilian dietitians assessed by the Portuguese version of ORTO-15

BACKGROUND: Orthorexia nervosa (ON) is described as an obsessive pathological behavior characterized by a strong preoccupation with healthy eating and the avoidance of foods or ingredients considered unhealthy by the subject. Although it is still not officially recognized as an eating disorder, previous studies have discussed its frequency in some groups and a fifteen-question test (ORTO-15) was developed elsewhere to assess ON behavior. OBJECTIVE: The present study aimed to evaluate ON behavior in a sample of Brazilian dietitians after testing the psychometric properties of the Portuguese version of ORTO-15. METHODS: A total of 392 dietitians answered an online version of the test. The answers were analyzed regarding ON tendency, according with the scoring grid proposed by its authors. Exploratory factor analysis was performed and internal consistency was assessed. RESULTS: It was found that three questions of the test presented loadings lower than 0.5. The 12 remaining question formed 3 factors with internal consistency of -0.51, 0.63 and 0.47. The answers of the participants to these questions revealed a tendency to orthorexic behavior, mainly regarding aspects such as: making food choices conditioned by worry about health status, evaluating food rather from nutritional quality than from its taste, believing that consuming healthy food may improve appearance, discrediting the influence of mood on eating behavior and banning food choices considered by them as eating transgressions. CONCLUSION: There is no evidence of the validity and reliability of the ORTO-15 with the initial psychometric evaluation performed. Further analyses are needed. Nevertheless, it was possible to observe a high frequency of orthorexic behavior among the studied Brazilian dietitians. However, additional studies are needed to completely understand dietitians behavior toward ON. (Eat. Weight Disord. 17: e29-c35, 2012). (C) 2012, Editrice Kurtis

A comparison between diuretics and angiotensin-receptor blocker agents in patients with stage I hypertension (PREVER-treatment trial): study protocol for a randomized double-blind controlled trial

Abstract Background Cardiovascular disease is the leading cause of death in Brazil, and hypertension is its major risk factor. The benefit of its drug treatment to prevent major cardiovascular events was consistently demonstrated. Angiotensin-receptor blockers (ARB) have been the preferential drugs in the management of hypertension worldwide, despite the absence of any consistent evidence of advantage over older agents, and the concern that they may be associated with lower renal protection and risk for cancer. Diuretics are as efficacious as other agents, are well tolerated, have longer duration of action and low cost, but have been scarcely compared with ARBs. A study comparing diuretic and ARB is therefore warranted. Methods/design This is a randomized, double-blind, clinical trial, comparing the association of chlorthalidone and amiloride with losartan as first drug option in patients aged 30 to 70 years, with stage I hypertension. The primary outcomes will be variation of blood pressure by time, adverse events and development or worsening of microalbuminuria and of left ventricular hypertrophy in the EKG. The secondary outcomes will be fatal or non-fatal cardiovascular events: myocardial infarction, stroke, heart failure, evidence of new subclinical atherosclerosis and sudden death. The study will last 18 months. The sample size will be of 1200 participants for group in order to confer enough power to test for all primary outcomes. The project was approved by the Ethics committee of each participating institution. Discussion The putative pleiotropic effects of ARB agents, particularly renal protection, have been disputed, and they have been scarcely compared with diuretics in large clinical trials, despite that they have been at least as efficacious as newer agents in managing hypertension. Even if the null hypothesis is not rejected, the information will be useful for health care policy to treat hypertension in Brazil. Clinical trials registration number ClinicalTrials.gov: NCT00971165

U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration

The LA-MC-ICP-MS method applied to U-Pb in situ dating is still rapidly evolving due to improvements in both lasers and ICP-MS. To test the validity and reproducibility of the method, 5 different zircon samples, including the standard Temora-2, ranging in age between 2.2 Ga and 246 Ma, were dated using both LA-MC-ICP-MS and SHRIMP. The selected zircons were dated by SHRIMP and, after gentle polishing, the laser spot was driven to the same site or on the same zircon phase with a 213 nm laser microprobe coupled to a multi-collector mixed system. The data were collected with a routine spot size of 25 μm and, in some cases, of 15 and 40 μm. A careful cross-calibration using a diluted U-Th-Pb solution to calculate the Faraday reading to counting rate conversion factors and the highly suitable GJ-1 standard zircon for external calibrations were of paramount importance for obtaining reliable results. All age results were concordant within the experimental errors. The assigned age errors using the LA-MC-ICP-MS technique were, in most cases, higher than those obtained by SHRIMP, but if we are not faced with a high resolution stratigraphy, the laser technique has certain advantages.

HTLV-1/2 seroprevalence and coinfection rate in Brazilian first-time blood donors: an 11-year follow-up

The seroprevalence and geographic distribution of HTLV-1/2 among blood donors are extremely important to transfusion services. We evaluated the seroprevalence of HTLV-1/2 infection among first-time blood donor candidates in Ribeirão Preto city and region. From January 2000 to December 2010, 1,038,489 blood donations were obtained and 301,470 were first-time blood donations. All samples were screened with serological tests for HTLV-1/2 using enzyme immunoassay (EIA). In addition, the frequency of coinfection with hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), Chagas disease (CD) and syphilis was also determined. In-house PCR was used as confirmatory test for HTLV-1/2. A total of 296 (0.1%) first-time donors were serologically reactive for HTLV-1/2. Confirmatory PCR of 63 samples showed that 28 were HTLV-1 positive, 13 HTLV-2 positive, 19 negative and three indeterminate. Regarding HTLV coinfection rates, the most prevalent was with HBV (51.3%) and HCV (35.9%), but coinfection with HIV, CD and syphilis was also detected. The real number of HTLV-infected individual and coinfection rate in the population is underestimated and epidemiological studies like ours are very informative.

Lab-on-a-chip: the future in water quality detection

Interpretación realizada por las alumnas en prácticas de la Facultad de Traducción e Interpretación, Estíbaliz López-Leiton Trujillo, Danaide Rodríguez Hernández, Esther Ramírez Millares.

Identificazione delle Lamine di tipo A come nuovi substrati della protein chinasi Akt/PKB

Akt (also called PKB) is a 63 kDa serine/threonine kinase involved in promotion of cell survival, proliferation a nd metabolic responses downstream the phosphoinositide-3-kinase (PI 3-kinase) signaling pathway. In resting cells, Akt is a predominantly cytosolic enzyme; however generation of PI 3-kinase lipid products recruits Akt to the plasma membrane, resulting in a conformational change which confers full enzymatic activity through the phosphorylation of the membrane-bound protein at two residues, Thr308, and Ser473. Activated Akt redistributes to cytoplasm and nucleus, where phosphorylation of specific substrates occurs. Both the presence and the activity of Akt in the nucleus have been described. An interesting mechanism that mediates nuclear translocation of Akt has been described in human mature T-cell leukemia: the product of TCL1 gene, Tcl1, interacts with the PH domain of phosphorylated Akt, thus driving Akt to the nucleus. In this context, Tcl1 may act as a direct transporter of Akt or may contribute to the formation of a complex that promotes the transport of active Akt to the nucleus, where it can phosphorylate nuclear substrates. A well described nuclear substrate if Foxo. IGF-1 triggers phosphorylation of Foxo by Akt inside the nucleus, where phospho-Foxo associates to 14.3.3 proteins that, in turn, promote its export to the cytoplasm where it is sequestered. Remarkably, Foxo phosphorylation by Akt has been shown to be a crucial event in Akt-dependent myogenesis. However, most Akt nuclear substrates have so far remained elusive, as well as nuclear Akt functions. This lack of information prompted us to undertake a search of substrates of Akt in the nucleus, by the combined use of 2D-separation/mass spectrometry and anti-Akt-phosphosubstrate antibody. This study presents evidence of A-type lamins as novel nuclear substrates of Akt. Lamins are type V intermediate filaments proteins found in the nucleus of higher eukaryotes where, together with lamin-binding proteins, they form the lamina at the nuclear envelope, providing mechanical stability for the nuclear membrane. By coimmunoprecipitation, it is demonstrated here that endogenous lamin A and Akt interact, and that A-type lamins are phosphorylated by Akt both in vitro and in vivo. Moreover, by phosphoaminoacid analysis and mutagenesis, it is further demonstrated that Akt phosphorylates lamin A at Ser404, and, more importantly, that while lamin A/C phosphorylation is stable throughout the cell cycle, phosphorylation of the precursor prelamin A becomes detectable as cells enter the G2 phase, picking at G2/M. This study also shows that lamin phosphorylation by Akt creates a binding site for 14.3.3 adaptors which, in turn, promote prelamin A degradation. While this mechanism is in agreement with a general role of Akt in the regulation of a subset of its substrates, opposite to what has been described, degradation is not mediated through a ubiquitination and proteasomal mechanism but through a lysosomal pathway, as indicated by the reverting action of the lysosomal inhibitor cloroquine. Phosphorylation is a key event in the mitotic breakdown of the nuclear lamina. However, the kinases and the precise sites of phosphorylation are scarcely known. Therefore, these results represent an important breakthrough in this very significant but understudied area. The phosphorylation of the precursor protein prelamin A and its subsequent degradation at G2/M, when both the nuclear envelop and the nuclear lamina disassemble, can be view as part of a mechanism to dispose off the precursor that is not needed in this precise context. The recently reported finding that patients affected by Emery-Dreifuss muscular dystrophy carry a mutation at Arg 401, in the Akt phosphorylation motif, open new perspective that warrant further investigation in this very important field.

Programmazione funzionale in spazio logaritmico: una libreria di funzione aritmetiche

In questa Tesi forniamo una libreria di funzioni aritmetiche che operano in spazio logaritmico rispetto all'input. Partiamo con un'analisi dei campi in cui è necessario o conveniente porre dei limiti, in termini di spazio utilizzato, alla computazione di un determinato software. Vista la larga diffusione del Web, si ha a che fare con collezioni di dati enormi e che magari risiedono su server remoti: c'è quindi la necessità di scrivere programmi che operino su questi dati, pur non potendo questi dati entrare tutti insieme nella memoria di lavoro del programma stesso. In seguito studiamo le nozioni teoriche di Complessità, in particolare quelle legate allo spazio di calcolo, utilizzando un modello alternativo di Macchina di Turing: la Offline Turing Machine. Presentiamo quindi un nuovo “modello” di programmazione: la computazione bidirezionale, che riteniamo essere un buon modo di strutturare la computazione limitata in spazio. Forniamo poi una “guida al programmatore” per un linguaggio di recente introduzione, IntML, che permettere la realizzazione di programmi logspace mantenendo però il tradizionale stile di programmazione funzionale. Infine, per mostrare come IntML permetta concretamente di scrivere programmi limitati in spazio, realizziamo una libreria di funzioni aritmetiche che operano in spazio logaritmico. In particolare, mostriamo funzioni per calcolare divisione intera e resto sui naturali, e funzioni per confrontare, sommare e moltiplicare numeri espressi come parole binarie.

Caracterización del ensuciamiento en membranas de ultrafiltración mediante parámetros de medida de resistencia en operación de flujo cruzado

Programa de Doctorado: Ingeniería Ambiental y Desalinización

Riparazione del danno ischemico ostruttivo del miocardio mediante cellule staminali mesenchimali sottoposte a stimolazione elettromeccanica in bioreattore

Nell’ambito dell’ingegneria dei tessuti, la possibilità di rigenerazione del miocardio post-infartuale è un argomento “caldo”, che suscita grandi speranze ma solleva altrettanto grandi interrogativi - sostenuti dal sussistere di dubbi di base sulle scelte operative praticabili. Esiste tuttavia concordanza nel considerare fondamentale l’utilizzo di un “supporto” che possa mantenere nella sede peri-infartuale le cellule competenti. Infatti, la semplice iniezione di cellule staminali per via endovenosa o direttamente nell’area infartuata non si è dimostrata particolarmente efficace, soprattutto a causa della cospicua perdita cellulare che si verifica rapidamente dopo il trapianto. Ci si orienta quindi verso la strategia di seminare cellule in grado di transdifferenziare in senso muscolare cardiaco su un materiale biocompatibile in vitro e di impiantare successivamente il costrutto ottenuto in vivo dove ci si attende il riassorbimento del biomateriale e l’integrazione delle cellule. Tuttavia, mentre in altri settori della medicina - quali ortopedia e dermatologia - l’impiego di pseudotessuti ingegnerizzati ha già permesso di conseguire ottimi risultati nella rigenerazione di tessuti danneggiati, allo stato attuale, i progressi ottenuti nell’ambito della rigenerazione del miocardio infartuato appaiono ancora aneddotici e distanti dall’ottenere protocolli condivisi per l’impiego in clinica. Il lavoro presentato in questa ricerca, condotto grazie alla sinergia di competenze interdisciplinari negli ambiti chimico, biologico e dell’ingegneria biomedica meccanica ed elettronica, è uno studio di fattibilità di una metodica standardizzata in grado di indirizzare cellule staminali mesenchimali (MSCs) indifferenziate verso l’acquisizione in vitro di caratteri fenotipici confrontabili con quelli delle cellule muscolari cardiache attraverso il paradigma della coltura dinamica in bioreattore. Il prototipo di bioreattore impiegato, in quanto sviluppato originalmente nel corso di questa attività di ricerca, presenta rispetto ad altri strumenti descritti l’innovazione e il vantaggio di non richiedere l’utilizzo di un incubatore, in quanto esso stesso permette di coltivare cellule al suo interno in condizioni controllate di temperatura, pH e concentrazione di CO2. La sua flessibilità operativa consente di impostare e controllare da personal computer leggi di moto di qualsiasi forma anche con cicliche molto veloci. Infine, la presenza di estensimetri in grado di misurare finemente la variazione di tensione esercitata sulla matrice polimerica utilizzata, posta in trazione tra due afferraggi, permette di applicare nel tempo una forza di stiramento costante, ottenendo deformazioni controllate e risultati riproducibili in termini di modificazioni cellulari. Il superamento delle problematiche sorte durante la fase di messa a punto del sistema, che deve essere ritenuto parte integrante del lavoro di sviluppo condotto, ha permesso di studiare l’adattamento di MSCs allo stiramento ciclico, mostrando che questo effettivamente determina alcune differenze fenotipiche rispetto al controllo statico. Inoltre le cellule hanno acquistato una disposizione orientata lungo l’asse longitudinale delle fibre, dato questo particolarmente importante se si considera la disposizione ordinata delle cellule del miocardio, le quali costituiscono un vero e proprio sincizio, indispensabile per una diffusione sincrona dell’impulso elettrico di contrazione. La creazione di uno pseudotessuto cardiaco ottimale richiederà ovviamente ulteriore lavoro, ma la metodica qui presentata si propone al tempo stesso come uno strumento di studio e come una strategia operativa per un approccio innovativo e standardizzabile alla medicina rigenerativa del miocardio.