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Parkinson's disease is a degenerative, chronic and progressive disease, characterized by motor dysfunctions. Patients also exhibit non-motor symptoms, such as affective and sleep disorders. Sleep disorders can potentiate clinical and neuropathological features and lead to worse prognosis. The goal of this study was to evaluate the effects of sleep deprivation (SD) in mice submitted to a progressive pharmacological model of Parkinsonism (chronic administration with a low dose of reserpine). Male Swiss mice received 20 injections of reserpine (0.1 mg/kg) or vehicle, on alternate days. SD was applied before or during reserpine treatment and was performed by gentle handling for 6 h per day for 10 consecutive days. Animals were submitted to motor and non-motor behavioral assessments and neurochemical evaluations. Locomotion was increased by SD and decreased by reserpine treatment. SD during treatment delayed the onset of catalepsy, but SD prior to treatment potentiated reserpine-induced catalepsy. Thus, although SD induced an apparent beneficial effect on motor parameters, a delayed deleterious effect on alterations induced by reserpine was found. In the object recognition test, both SD and reserpine treatment produced cognitive deficits. In addition, the association between SD and reserpine induced anhedonic-like behavior. Finally, an increase in oxidative stress was found in hippocampus of mice subjected to SD, and tyrosine hydroxylase immunoreactivity was reduced in substantia nigra of reserpine-treated animals. Results point to a possible late effect of SD, aggravating the deficits in mice submitted to the reserpine progressive model of PD. [ABSTRACT FROM AUTHOR]

Despite recent efforts to search for biomarkers for the pre-symptomatic diagnosis of Parkinson's disease (PD), the presence of risk factors, prodromal signs, and family history still support the classification of individuals at risk for this disease. Human epidemiological studies are useful in this search but fail to provide causality. The study of well-known risk factors for PD in animal models can help elucidate mechanisms related to the disease's etiology and contribute to future prevention or treatment approaches. This narrative review aims to discuss animal studies that investigated four of the main risk factors and/or prodromal signs related to PD: advanced age, male sex, sleep alterations, and depression. Different databases were used to search the studies, which were included based on their relevance to the topic. Although still in a reduced number, such studies are of great relevance in the search for evidence that leads to a possible early diagnosis and improvements in methods of prevention and treatment. [ABSTRACT FROM AUTHOR]

Copyright of HOLOS is the property of Instituto Federal do Rio Grande do norte - IFRN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spatial arrangement of distinct Amazonian environments through time and its effect on specialized biota remain poorly known, fueling long-lasting debates about drivers of biotic diversification. We address the late Quaternary sediment deposition that assembled the world's largest seasonally flooded ecosystems. Genome sequencing was used to reconstruct the demographic history of bird species specialized in either early successional vegetation or mature floodplain forests. Sediment deposition that built seasonally flooded habitats accelerated throughout the Holocene (last 11,700 years) under sea level highstand and intensification of the South American Monsoon, at the same time as global increases in atmospheric methane concentration. Bird populations adapted to seasonally flooded habitats expanded due to enlargement of Amazonian river floodplains and archipelagos. Our findings suggest that the diversification of the biota specialized in seasonally flooded habitats is coupled to sedimentary budget changes of large rivers, which rely on combined effects of sea level and rainfall variations. This study found that millennial periods of higher rainfall combined with rising sea level enhanced sediment accumulation in Amazonian rivers valleys. This fuelled synchronous expansion of vegetation adapted to seasonally flooded substrates and its specialized bird populations, showing how global climate changes can affect specific Amazonian species. [ABSTRACT FROM AUTHOR]

Climate change threats agriculture, mainly in developing countries. Understanding the vulnerability of farmers is very important to counteract the negative impacts. Therefore, this paper aims to analyze the degree of vulnerability to climate change of farmers of the Rio das Contas Basin, Brazil, based on their degree of sensibility, exposure, and adaptive capacity. Variations in exposure and vulnerability indexes between regional biomes were calculated. The sensibility index was higher than 50% in all municipalities. The exposure index was over 60% in most municipalities. A value of the adaptive capacity index, sufficient to reduce vulnerability, was not observed in any municipality. The vulnerability index was higher than 66% in more than half of the municipalities. Exposure and vulnerability indexes varied with the biome. The vulnerability is the result of high exposure and sensibility combined with low adaptive capacity. This suggests the need for investment to minimize these effects and mitigation activities to counter the negative impacts of future climate variability. [ABSTRACT FROM AUTHOR]

Dissemination of wireless networks and mobile devices, such as smartphones, has motivated the appearance of several types of location-based services. Consequently, the interest in low-complexity cost-effective mobile positioning techniques against the traditional method based on global positioning system has emerged. An interesting alternative is to utilize radio frequency (RF) signals to estimate the location of mobile terminals, as in multilateration and RF fingerprinting techniques. In this context, the objective of this work is to propose a new radio strength signal-based user equipment location method using a machine learning regression-based model to find directly the geographical coordinates of the mobile user in cellular networks. Numerical results show that, in most cases, the proposed method can meet the location accuracy requirements established by the Federal Communications Commission for network-based localization methods. [ABSTRACT FROM AUTHOR]

Hepatitis E has always been related to morbidity in pregnant women. Its epidemiology is not well understood in Brazil. Therefore, we tested sera from 209 pregnant women and 199 female blood donors, collected at a single center in Curitiba, Brazil. The Wantai assay was used for testing the anti‐hepatitis E virus (anti‐HEV), immunoglobulin G (IgG), and an in‐house polymerase chain reaction process for testing HEV RNA. Anti‐HEV was detected in 22.5% of the total group, 19% in the pregnant women group, and 26% in the blood donor group (P = 0.11), a much higher prevalence when compared with other studies in Brazil. Demographical analysis showed that 92.4% were born in the South Region of Brazil, 4.9% in the Southeast, and 2.7% were distributed over other regions of the country. With respect to their origin, 99% were from the South, 0.7% from the Southeast, and 0.2% from the Central‐West regions. Income, education, race, number of pregnancies, and abortion did differ significantly when comparing both the groups (P < 0.001). Age >30 (P = 0.012) and the number (>3) of pregnancies (P = 0.008) were related to anti‐HEV positivity. All anti‐HEV IgG–positive females were HEV RNA negative. In conclusion, HEV positivity was found in one out of five young women, which showed an urgent need for further epidemiological studies in Brazil. [ABSTRACT FROM AUTHOR]

The goal of this study was to confirm the vasopressor and cardiac effects of POTENAY® INJETÁVEL (POT), a mephentermine‐based product, given to cattle with induced vascular/cardiac depression. Ten healthy Holstein cattle (206 ± 13 kg) followed a randomized‐complete‐block design (RCBD) utilizing crossover study design. Each animal randomly received (1 ml/25 kg, IM) of either POT (n = 10) or volume‐matched placebo control (0.9%NaCl, CP, n = 10). A subset of animals (n = 5) received POT first (day 0) while the remaining (n = 5) received CP; after a six‐day washout period, cattle received the opposite compound. Animals were anesthetized and catheterized for systemic/left ventricular hemodynamic monitoring. Myocardial dysfunction/hypotension was induced by increasing the end‐tidal isoflurane concentration until arterial blood pressure was 20% lower than at baseline and remained stable. Once the animal was determined to be hypotensive and hemodynamically stable, steady‐state hypotensive baseline data (BL2) were acquired, and treatment with either POT or CP was given. Data were acquired post‐treatment at every 15 min for 90 min. POT improved cardiac output (+68 L/min, ±14%, p < 0.05), MAP (+14 mmHg, ±4%, p < 0.05), HR (+22 bpm, ±8%, p < 0.05), and peak rates of ventricular pressure change during both systole (dP/dtmax: +37 mmHg/s ±13%, p < 0.05) and diastole (dP/dtmin: +31 mmHg/s, ±7%, p < 0.05). No improvements were noted following placebo‐control administration. Results indicate that POT improves cardiac performance and systemic hemodynamics in cattle with induced cardiovascular depression when given as single intramuscular injection. [ABSTRACT FROM AUTHOR]

Abstract: Background: It is of great value to develop valid instruments to estimate food consumption; for this purpose, the triads method has been applied in validation studies of dietary intake to evaluate the correlation between three measurements [food frequency questionnaire (FFQ), reference method and biomarker]. The main aim of the present study was to validate a FFQ for Brazilian adults by means of the method of triads by estimating the ingestion of total fatty acids based on the level of saturation. Methods: The present study enrolled 152 Brazilian adults of both sexes, who were residents in the city of Viçosa, Brazil. The ingestion of total saturated, monounsaturated, polyunsaturated, trans, linoleic and linolenic fatty acids was assessed by means of a FFQ, two food records, and biomarkers, which were detected by gas chromatography. The validation coefficients were calculated using the method of triads and concordance was determined by Kappa statistics. Results: The FFQ was considered an adequate dietary method, because, based on the validation coefficients, it estimates the intake of total fat (0.84), as well as linolenic (0.90) and linoleic acids (0.31). A high concordance rate was confirmed for all nutrients assessed by the FFQ and food records. Regarding the biomarkers, linolenic acid and linoleic acid presented greater concordance. Conclusions: According to the validation coefficients, the FFQ precisely estimated total fat, linolenic acid and linoleic acid contents. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) is a known food pathogen, which main reservoir is the intestine of ruminants. The abundance of different STEC lineages in nature reflect a heterogeneity that is characterised by the differential expression of certain genotypic characteristics, which in turn are influenced by the environmental conditions to which the microorganism is exposed. Bacterial homeostasis and stress response are under the control of the alarmone guanosine tetraphosphate (ppGpp), which intrinsic levels varies across the E. coli species. In the present study, 50 STEC isolates from healthy sheep were evaluated regarding their ppGpp content, cytotoxicity and other relevant genetic and phenotypic characteristics. We found that the level of ppGpp and cytotoxicity varied considerably among the examined strains. Isolates that harboured the stx2 gene were the least cytotoxic and presented the highest levels of ppGpp. All stx2 isolates belonged to phylogroup A, while strains that carried stx1 or both stx1 and stx2 genes pertained to phylogroup B1. All but two stx2 isolates belonged to the stx2b subtype. Strains that belonged to phylogroup B1 displayed on average low levels of ppGpp and high cytotoxicity. Overall, there was a negative correlation between cytotoxicity and ppGpp. [ABSTRACT FROM AUTHOR]

When a dysfunction occurs in any component of the stomatognathic system, temporomandibular disorders ( TMD) may originate. The aim of this study was to compare the deviations, displacement and the execution speed of mandibular movements among asymptomatic participants and those with TMD. Convenience sampling was used; forty participants diagnosed by clinical evaluation following the Research Diagnostic Criteria for Temporomandibular Disorders were divided into three groups: arthropathy ( GART, 10 participants, 40% men), myopathy ( GMYO, 10 participants, 30% men), and the control group ( CG, 20 asymptomatic participants, 25% men). Participants were asked to perform the movements of free maximal mouth opening and closing, right and left lateral excursions, and protrusion with sliding teeth contacts. The mandibular trajectory was recorded using opto-electronic devices tracking reflective markers placed in front of the 'soft tissue pogonion point'. The movements were analysed on the following axis: x - medial-lateral, y - vertical, z - antero-posterior. Significative differences were found in CGx GART - unassisted maximal mouth opening and closing projection on y-axis (OCY), CGx GMYO - unassisted maximal mouth opening and closing projection on x-axis (OCX), and in the measures Opening lateral deviation on x-axis (OLDX), closing lateral deviation on x-axis (CLDX) and in the measures of speed for both. In regard to GARTx GMYO, a significative difference was found in Protrusion lateral deviation on x-axis (PLDX) 'Conover-Iman Test of Multiple Comparisons Using Rank Sums' using Bonferroni correction ( P < 0·05). In conclusion, the total opening movements in individuals with TMD tended to have higher deviation than in those asymptomatic individuals and a reduction in the speed of movements. [ABSTRACT FROM AUTHOR]

Copyright of Archivos de Zootecnia is the property of Archivos de Zootecnia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of HOLOS is the property of Instituto Federal do Rio Grande do norte - IFRN and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Health-care workers (HCWs) on the frontlines of the 2019 Coronavirus Disease 2019 (COVID-19) have a high risk of acquiring and dying from the disease. Brazil is a country with high morbimortality and ranks highest in general mortality from COVID-19. A large proportion of medical doctors (MDs) is dying, impacting in the workforce. As part of the research by Fiocruz on working conditions among HCWs, we have conducted this study of death among MDs. We analyzed data from Federal Council of Medicine, the only national platform with details about deaths in MDs. A broad search of other sources, including the Ministry of Health, was done, but unfortunately, the data does not exist. A total of 622 MDs died from March 2020 to March 2021: 87.6% male and 75% over age 60. The Southeast had the highest percentage (34.7%), followed by the Northeast (27.2%), and rankings by state showed Rio de Janeiro (15.8%), followed by São Paulo, Pará, Paraná and Paraíba, totalizing 50.1%. The specialties with highest mortality were gynecology (12.2%), pediatrics (10.0%), internal medicine (9.3%), general surgery (7.8%) and cardiology (7.6%). May 2020 was the month of worst mortality (16.9%) followed by July and June. A slow decline was observed until October, when Brazil begun to experience the ‘‘second wave’’. The vaccination of MDs began at the end of January 2021 and has not been sufficient time to evaluate the impact on morbimortality. The results of a study of 50 professional categories are under analysis and will be published soon as well as a study of ‘‘invisible’’ HCWs, who do not have specific training but are essential to supporting health care system, from primary care units to high-complexity hospitals. We hope that the results of these studies will improve links among managers, those who define public policies, and union leaders, achieving better workplace and living conditions, minimizing health and socioeconomic disparities. Key messages: This study is about death by COVID-19 among medical doctors in Brazil, as part of a large one on professional categories, essentials to supporting health care system, conducted by FIOCRUZ. This stdy is part of a large one on professional categories, essentials to supporting health care system, conducted by FIOCRUZ. [ABSTRACT FROM AUTHOR]

Context. The detection of reflected light from an exoplanet is a difficult technical challenge at optical wavelengths. Even though this signal is expected to replicate the stellar signal, not only is it several orders of magnitude fainter, but it is also hidden among the stellar noise. Aims. We apply a variant of the cross-correlation technique to HARPS observations of 51 Peg to detect the reflected signal from planet 51 Peg b. Methods. Our method makes use of the cross-correlation function (CCF) of a binary mask with high-resolution spectra to amplify the minute planetary signal that is present in the spectra by a factor proportional to the number of spectral lines when performing the cross correlation. The resulting cross-correlation functions are then normalized by a stellar template to remove the stellar signal. Carefully selected sections of the resulting normalized CCFs are stacked to increase the planetary signal further. The recovered signal allows probing several of the planetary properties, including its real mass and albedo. Results. We detect evidence for the reflected signal from planet 51 Peg b at a significance of 3σnoise. The detection of the signal permits us to infer a real mass of 0:46+0:06 >-0:01 MJup (assuming a stellar mass of 1:04 MSun) for the planet and an orbital inclination of 80+10-19 degrees. The analysis of the data also allows us to infer a tentative value for the (radius-dependent) geometric albedo of the planet. The results suggest that 51Peg b may be an inflated hot Jupiter with a high albedo (e.g., an albedo of 0.5 yields a radius of 1:9 ± 0:3 RJup for a signal amplitude of 6:0 ± 0:4 × 10-5). Conclusions. We confirm that the method we perfected can be used to retrieve an exoplanet's reflected signal, even with current observing facilities. The advent of next generation of instruments (e.g. VLT-ESO/ESPRESSO) and observing facilities (e.g. a new generation of ELT telescopes) will yield new opportunities for this type of technique to probe deeper into exoplanets and their atmospheres. [ABSTRACT FROM AUTHOR]

Context. In the near future, new instruments such as ESPRESSO will arrive, allowing us to reach a precision in radial velocity measurements on the order of 10 cm s–1. At this level of precision, several noise sources that until now have been outweighed by photon noise will start to contribute significantly to the error budget. The telluric lines that are not neglected by the masks for the radial velocity computation, here called micro-telluric lines, are one such noise source. Aims. In this work we investigate the impact of micro-telluric lines in the radial velocities calculations. We also investigate how to correct the effect of these atmospheric lines on radial velocities. Methods. The work presented here follows two parallel lines. First, we calculated the impact of the micro-telluric lines by multiplying a synthetic solar-like stellar spectrum by synthetic atmospheric spectra and evaluated the effect created by the presence of the telluric lines. Then, we divided HARPS spectra by synthetic atmospheric spectra to correct for its presence on real data and calculated the radial velocity on the corrected spectra. When doing so, one considers two atmospheric models for the synthetic atmospheric spectra: the LBLRTMand TAPAS. Results. We find that the micro-telluric lines can induce an impact on the radial velocity calculation that can already be close to the current precision achieved with HARPS, and so its effect should not be neglected, especially for future instruments such as ESPRESSO.Moreover, we find that the micro-telluric lines' impact depends on factors, such as the radial velocity of the star, airmass, relative humidity, and the barycentric Earth radial velocity projected along the line of sight at the time of the observation. [ABSTRACT FROM AUTHOR]

Context:No long-term studies have compared centrally acting drugs for treating obesity.Objective:To compare the efficacy and safety of diethylpropion (DEP), fenproporex (FEN), mazindol (MZD), fluoxetine (FXT) and sibutramine (SIB) in promoting weight loss.Design and Setting:A prospective, randomized, placebo (PCB)-controlled study conducted at a single academic institution.Patients:A total of 174 obese premenopausal women.Intervention:Participants randomly received DEP 75 mg (n=28), FEN 25 mg (n=29), MZD 2 mg (n=29), SIB 15 mg (n=30), FXT 20 mg (n=29) or PCB (n=29) daily over 52 weeks. Diet and physical activity were encouraged.Main Outcome Measures:The primary endpoints were changes in body weight and the proportion of women who achieved at least 5% weight loss by week 52 in the intent-to-treat population. Other measurements included anthropometry, safety, metabolic and cardiovascular parameters.Results:Weight loss was greater than PCB (−3.1±4.3 kg) with DEP (−10.0±6.4 kg; P<0.001), SIB (−9.5±5.9 kg; P<0.001), FEN (−7.8±6.9 kg; P<0.01) and MZD (−7.4±4.9 kg; P<0.01) but not with FXT (−2.5±4.1 kg). Ten (33.3%) women lost⩾5% of their initial weight with PCB, compared with 20 (71.4%; P<0.001) with DEP, 20 (69%; P<0.02) with FEN, 21 (72.4%; P<0.01) with MZD, 22 (73.3%; P<0.001) with SIB and 10 (35.5%) with FXT. Each medically treated group experienced more adverse events compared with PCB (P<0.001). Compared with PCB, constipation was more prevalent with DEP, SIB and MZD (P<0.01); anxiety was more prevalent with DEP (P=0.01); and irritability occurred more frequently with DEP and FEN (P=0.02). Significant improvements in the depression and anxiety scores, binge-eating episodes and quality of life correlated with weight loss.CONCLUSION:The centrally acting drugs DEP, FEN, MZD and SIB were more effective than PCB in promoting weight loss in obese premenopausal women, with a satisfactory benefit-risk profile. [ABSTRACT FROM AUTHOR]

Diets rich in saturated fats may contribute to the loss of pancreatic β-cells in type 2 diabetes. JunB, a member of the activating protein 1 (AP-1) transcription factor family, promotes β-cell survival and mediates part of the beneficial effects of GLP-1 agonists. In this study we interrogated the molecular mechanisms involved in JunB-mediated β-cell protection from lipotoxicity. The saturated fatty acid palmitate decreased JunB expression, and this loss may contribute to β-cell apoptosis, as overexpression of JunB protected cells from lipotoxicity. Array analysis of JunB-deficient β-cells identified a gene expression signature of a downregulated endoplasmic reticulum (ER) stress response and inhibited AKT signaling. JunB stimulates XBP1 expression via the transcription factor c/EBPδ during ER stress, and forced expression of XBP1s rescued the viability of JunB-deficient cells, constituting an important antiapoptotic mechanism. JunB silencing inhibited AKT activation and activated the proapoptotic Bcl-2 protein BAD via its dephosphorylation. BAD knockdown reversed lipotoxic β-cell death potentiated by JunB siRNA. Interestingly, XBP1s links JunB and AKT signaling as XBP1 knockdown also reduced AKT phosphorylation. GLP-1 agonists induced cAMP-dependent AKT phosphorylation leading to β-cell protection against palmitate-induced apoptosis. JunB and XBP1 knockdown or IRE1 inhibition decreased AKT activation by cAMP, leading to β-cell apoptosis. In conclusion, JunB modulates the β-cell ER stress response and AKT signaling via the induction of XBP1s. The activation of the JunB gene network and the crosstalk between the ER stress and AKT pathway constitute a crucial defense mechanism by which GLP-1 agonists protect against lipotoxic β-cell death. These findings elucidate novel β-cell-protective signal transduction in type 2 diabetes. [ABSTRACT FROM AUTHOR]

Context. The search for planets orbiting metal-poor stars is of utmost importance for our understanding of planet formation models. However, no dedicated searches have been conducted so far for very low mass planets orbiting such objects. Only a few cases of low-mass planets orbiting metal-poor stars are thus known. Amongst these, HD?41248 is a metal-poor, solar-type star on the orbit of which a resonant pair of super-Earth-like planets has been announced. This detection was based on 62 radial velocity measurements obtained with the HARPS spectrograph (public data). Aims. We present a new planet search program that is using the HARPS spectrograph to search for Neptunes and super-Earths that orbit a sample of metal-poor FGK dwarfs. We then present a detailed analysis of 162 additional radial velocity measurements of HD?41248, obtained within this program, with the goal of confirming the existence of the proposed planetary system. Methods. We analysed the precise radial velocities, obtained with the HARPS spectrograph, together with several stellar activity diagnostics and line profile indicators. Results. A careful analysis shows no evidence for the planetary system. One of the signals, with a period of ~25?days, is shown to be related to the rotational period of the star, and is clearly seen in some of the activity proxies. We were unable to convincingly retrieve the remaining signal (P ~ 18?days) in the new dataset. Conclusions. We discuss possible causes for the complex (evolving) signals observed in the data of HD?41248, proposing that they might be explained by the appearance and disappearance of active regions on the surface of a star with strong differential rotation, or by a combination of the sparse data sampling and active region evolution. [ABSTRACT FROM AUTHOR]

Androgen action is exerted through the androgen receptor. The normal 46,XY genital virilization depends on androgen receptor gene expression, which is tissue specific, and requires normal androgen receptor mRNA levels in androgen sensitive tissues. Hypospadias is a frequent male genital abnormality, potentially related to reduced androgen sensitivity in genital tissues. The aim of this study was to compare, by quantitative real time PCR, the amount of androgen receptor mRNA in cells obtained from the urethral mucosa of patients with middle idiopathic hypospadias with the androgen receptor mRNA levels observed in control phimosis subjects with eutopic urethral opening. Prepubertal individuals were studied, including 41 controls and 17 hypospadias patients with mean (SD) ages of 4.7 (2.1) years and 4.0 (3.0) years, respectively. We observed significantly less androgen receptor mRNA in the urethral mucosa of patients with hypospadias than in the controls (p = 0.002). The correlation between the level of androgen receptor mRNA expression and the penile size was almost statistically significant only in hypospadias patients (r = 0.47; p = 0.053). We also established the number of CAG repeats in exon 1 of the androgen receptor gene by GeneScan analysis. No significant difference was observed in the number of CAG repeats when patients and controls were compared. A negative correlation between the CAG repeats and penile size was detected in patients with hypospadias, but not in controls. Our data suggest that a critical lower level of androgen receptor mRNA expression could be a determining factor in the development of middle hypospadias. [ABSTRACT FROM AUTHOR]

In this work, a semi-analytical model was developed to determine the contrast-to-noise ratio (CNR) and the normalized average glandular dose (\barDgN) in digital mammography, taking into account interactions up to second order. The optimal x-ray spectra were investigated using a Figure of Merit (FOM), for different breast thicknesses (3\ cm\leqL\leq 7\ cm) and glandularities (20% and 50%), anti-scatter grids types, considering a-Se and CsI image receptors. The anode/filter combinations evaluated were: Mo/Mo, Mo/Rh, Rh/Rh, and a W anode combined with k-edge filters (Mo, Ru, Rh, Pd, Ag, Cd, In and Sn), for tube potential between 23 and 35 kVp. Results demonstrate that the W-anode spectra combined with k-edge filters show a superior performance compared to the Mo/Mo combination traditionally employed in mammography, for all conditions analyzed. The optimum general x-ray spectra for 3 cm, 5 cm and 7 cm breasts are, respectively, W/Mo at 23 kVp, W/Pd at 28 kVp and W/Ag at 30 kVp. For the a-Se receptor, the optimum filter atomic number is one unit higher than that obtained for the CsI, while the optimal tube potentials are the same. The optimal tube potential was up to 1-2 kVp greater for a linear grid than that obtained without grid or with a cellular grid. For breast thicker than 7 cm, the optimum filter atomic number also increases by one unit for a linear grid. Compared to standard technique, the performance improvement of a W anode with proper k-edge filters is more noticeable for thicker and denser breasts, for a a-Se receptor and a linear grid. Finally, it was verified that the semi-analytical model implemented provided results of optimum x-ray spectra in a fast and simple way, with a good agreement with those obtained experimentally or by Monte Carlo simulation. [ABSTRACT FROM PUBLISHER]

Background and Objectives Platelet transfusions are performed almost entirely according to expert experience. This study assessed the effectiveness of a restrictive guideline to reduce platelet transfusions in preterm infants. Methods A retrospective cohort of preterm infants with a birth weight of <1500 g had been born in 2 periods. In Period 1, a transfusion was indicated for a platelet count of <50 000/ml in clinically stable neonates or <100 000/ml in bleeding or clinically unstable infants. In Period 2, the indications were restricted to <25 000/ml in clinically stable neonates, or <50 000/ml in newborns who were either on mechanical ventilation, subject to imminent invasive procedures, within 72 h following a seizure, or extremely premature and <7 days old. A count of <100 000/ml was indicated for bleeding or major surgery. Results Periods 1 and 2 comprised 121 and 134 neonates, respectively. The rates of ventricular haemorrhage and intrahospital death were similar in both periods. The percentage of transfused infants, the odds of receiving a platelet transfusion, the mean platelet count before transfusion and the percentage of transfusions with a platelet count >50,000/ml were greater in Period 1. Among thrombocytopenic neonates, the percentage of transfused neonates and the number of transfusions were similar in both groups. Conclusion The restrictive guideline for platelet transfusions reduced the platelet count thresholds for neonatal transfusions without increasing the rate of ventricular haemorrhage. [ABSTRACT FROM AUTHOR]

Context. With the announced arrival of instruments such as ESPRESSO one can expect that several systematic noise sources on the measurement of precise radial velocity will become the limiting factor instead of photon noise. A stellar companion within the fiber is such a possible noise source. Aims. With this work we aim at characterizing the impact of a stellar companion within the fiber to radial velocity measurements made by fiber-fed spectrographs. We consider the contaminant star either to be part of a binary system whose primary star is the target star, or as a background/foreground star. Methods. To carry out our study, we used HARPS spectra, co-added the target with contaminant spectra, and then compared the resulting radial velocity with that obtained from the original target spectrum. We repeated this procedure and used different tunable knobs to reproduce the previously mentioned scenarios. Results. We find that the impact on the radial velocity calculation is a function of the difference between individual radial velocities, of the difference between target and contaminant magnitude, and also of their spectral types. For the worst-case scenario in which both target and contaminant star are well-centered on the fiber, the maximum contamination for a ɢ or Κ star may be higher than 10 cm s-1, on average, if the difference between target and contaminant magnitude is ▵ m < 10, and higher than 1 m/s if ▵ m < 8. If the target star is of spectral type M, ▵ m < 8 produces the same contamination of 10 cms-1, and a contamination may be higher than 1 m/s if ▵ m < 6. [ABSTRACT FROM AUTHOR]

Nutrient criteria as reference concentrations and trophic state boundaries are necessary for water management worldwide because anthropogenic eutrophication is a threat to the water uses. We compiled data on total phosphorus (TP), nitrogen (TN) and chlorophyll a (Chl a) from 17 subtropical reservoirs monitored from 2005-2009 in the São Paulo State (Brazil) to calculate reference concentrations through the trisection method (United States Environmental Protection Agency). By dividing our dataset into thirds we presented trophic state boundaries and frequency curves for the nutrient levels in water bodies with different enrichment conditions. TP and TN baseline concentrations (0.010 mg/L and 0.350 mg/L, respectively) were bracketed by ranges for temperate reservoirs available in the literature. We propose trophic state boundaries (upper limits for the oligotrophic category: 0.010 mg TP/L, 0.460 mg TN/L and 1.7 µg Chl a/L; for the mesotrophic: 0.030 mg TP/L, 0.820 mg TN/L and 9.0 µg Chl a/L). Through an example with a different dataset (from the Itupararanga Reservoir, Brazil), we encouraged the use of frequency curves to compare data from individual monitoring efforts with the expected concentrations in oligotrophic, mesotrophic and eutrophic regional systems. Such analysis might help designing recovery programs to reach targeted concentrations and mitigate the undesirable eutrophication symptoms in subtropical freshwaters. [ABSTRACT FROM AUTHOR]

Despite their importance for water management, long-term studies on trophic state are relatively scarce in subtropical reservoirs. We analyzed total phosphorus (TP), total nitrogen (TN) and chlorophyll a (Chi a) concentrations in the Billings Reservoir (Brazil) over time: Phase 1 (1977-1992, Tietê River water was pumped to Billings to increase energy generation, 100m3 s1); Phase 2 (19922007, Tiet O water was conveyed to Billings only in special cases for flood avoidance, 8 m3 s1); and Phase 3 (2007-2010, besides flood control, Billings received Tietê water treated by an in situ flotation system, 13 m3 5-1). We compared our results with data from 12 reservoirs to evaluate current (20052009) enrichment conditions. Phosphorus and nitrogen concentrations decreased (p <0.05, MANOVA) from Phase 1 to 2 and were stable thereafter. TN/TP ratios increment (1 977-2010) indicated shift from Nto P-limitation in the reservoir, affecting the phytoplankton. Nutrient levels in Billings are currently between the expected concentrations in mesotrophic and eutrophic reservoirs (0.03 mg L1 -1, median for the eutrophic waterbodies from the dataset. Although water quality in Billings has improved, nutrient inputs from Tieté River pumping episodes, diffuse and internal sources are still favoring biomass accrual and compromising water uses. [ABSTRACT FROM AUTHOR]

Summary Background Mohs micrographic surgery offers high cure rates of nonmelanoma skin cancers with optimal sparing of normal tissue. However, it is generally more time-consuming and labour-intensive than traditional surgery. Optical coherence tomography (OCT) is an emergent technology that has the potential to diagnose basal cell carcinoma (BCC) in vivo. Objective To compare the efficiency and accuracy of ex vivo OCT with frozen-section histology for identifying BCC in Mohs surgery. Methods Thirty-eight patients were enrolled. After the stages were taken, images were captured with an OCT microscope and subsequently processed for standard frozen sections. Results In total, 75 sections were scanned and the mean time to produce one OCT image was 7 min. In four of 26 positive haematoxylin-eosin sections and 23 of 49 negative sections, there was a good correlation with OCT images. The sensitivity and specificity were 19% and 56%, respectively. Conclusions It is possible to identify BCC with ex vivo OCT and this is more rapidly obtained than with haematoxylin-eosin frozen sections. However, tumour visualization in OCT was disappointing. Practical benefit may be obtained by optimizing this technology and combining it with other new diagnostic tools. [ABSTRACT FROM AUTHOR]

Pancreatic β-cell apoptosis is a key feature of diabetes mellitus and the mitochondrial pathway of apoptosis is a major mediator of β-cell death. We presently evaluated the role of the myeloid cell leukemia sequence 1 (Mcl-1), an antiapoptotic protein of the Bcl-2 family, in β-cells following exposure to well-defined β-cell death effectors, for example, pro-inflammatory cytokines, palmitate and chemical endoplasmic reticulum (ER) stressors. All cytotoxic stresses rapidly and preferentially decreased Mcl-1 protein expression as compared with the late effect observed on the other antiapoptotic proteins, Bcl-2 and Bcl-xL. This was due to ER stress-mediated inhibition of translation through eIF2α phosphorylation for palmitate and ER stressors and through the combined action of translation inhibition and JNK activation for cytokines. Knocking down Mcl-1 using small interference RNAs increased apoptosis and caspase-3 cleavage induced by cytokines, palmitate or thapsigargin, whereas Mcl-1 overexpression partly prevented Bax translocation to the mitochondria, cytochrome c release, caspase-3 cleavage and apoptosis induced by the β-cell death effectors. Altogether, our data suggest that Mcl-1 downregulation is a crucial event leading to β-cell apoptosis and provide new insights into the mechanisms linking ER stress and the mitochondrial intrinsic pathway of apoptosis. Mcl-1 is therefore an attractive target for the design of new strategies in the treatment of diabetes. [ABSTRACT FROM AUTHOR]

Pinheiros River (Brazil) plays a pivotal role in supplying water to Billings Reservoir, which presents multiple uses (human drinking, energy generation, irrigation, navigation, fishing and leisure). An intense monitoring program was performed during the years 2007 and 2008 to find out whether on site flotation is a feasible solution or not for improving the water quality of this urban river, attenuating the pollutants load caused by the water pumping to the reservoir (approximately 10m3 s-1). The monitoring of 18 variables (13,429 laboratorial analysis during the period of 490 days), suggested that despite the convenience of the on site approach for water treatment, especially for rivers located in fully urbanized areas, the flotation system is not enough itself to recover Pinheiros River water quality, given the several constraints that apply. Total phosphorus removal was high in percentage terms (about 90%), although the remaining concentrations were not so low (mean of 0.05mg L-1). The removal efficiency of some variables was insufficient, leading to high final mean concentrations of metals [e.g. aluminium (0.29mgL-1), chromium (0.02mgL-1) and iron (1.1mgL-1)] as well as nitrogen-ammonia (25.8mgL-1) and total suspended solids (18mgL-1) in the treated water. [ABSTRACT FROM AUTHOR]

Beta cell failure is a crucial component in the pathogenesis of type 2 diabetes. One of the proposed mechanisms of beta cell failure is local inflammation, but the presence of pancreatic islet inflammation in type 2 diabetes and the mechanisms involved remain under debate. Chemokine and cytokine expression was studied by microarray analysis of laser-capture microdissected islets from pancreases obtained from ten non-diabetic and ten type 2 diabetic donors, and by real-time PCR of human islets exposed to oleate or palmitate at 6 or 28 mmol/l glucose. The cellular source of the chemokines was analysed by immunofluorescence of pancreatic sections from individuals without diabetes and with type 2 diabetes. Microarray analysis of laser-capture microdissected beta cells showed increased chemokine and cytokine expression in type 2 diabetes compared with non-diabetic controls. The inflammatory response in type 2 diabetes was mimicked by exposure of non-diabetic human islets to palmitate, but not to oleate or high glucose, leading to the induction of IL-1β, TNF-α, IL-6, IL-8, chemokine (C-X-C motif) ligand 1 (CXCL1) and chemokine (C-C motif) ligand 2 (CCL2). Interference with IL-1β signalling abolished palmitate-induced cytokine and chemokine expression but failed to prevent lipotoxic human islet cell death. Palmitate activated nuclear factor κB (NF-κB) in human pancreatic beta and non-beta cells, and chemically induced endoplasmic reticulum stress caused cytokine expression and NF-κB activation similar to that occurring with palmitate. Saturated-fatty-acid-induced NF-κB activation and endoplasmic reticulum stress may contribute to IL-1β production and mild islet inflammation in type 2 diabetes. This inflammatory process does not contribute to lipotoxicity ex vivo, but may lead to local chemokine release. [ABSTRACT FROM AUTHOR]

Chronic inflammation and pro-inflammatory cytokines are important mediators of pancreatic β-cell destruction in type 1 diabetes (T1D). We presently show that the cytokines IL-1β+IFN-γ and different ER stressors activate the Bcl-2 homology 3 (BH3)-only member death protein 5 (DP5)/harakiri (Hrk) resulting in β-cell apoptosis. Chemical ER stress-induced DP5 upregulation is JNK/c-Jun-dependent. DP5 activation by cytokines also involves JNK/c-Jun phosphorylation and is antagonized by JunB. Interestingly, cytokine-inducted DP5 expression precedes ER stress: mitochondrial release of cytochrome c and ER stress are actually a consequence of enhanced DP5 activation by cytokine-mediated nitric oxide formation. Our findings show that DP5 is central for β-cell apoptosis after different stimuli, and that it can act up- and downstream of ER stress. These observations contribute to solve two important questions, namely the mechanism by which IL-1β+IFN-γ induce β-cell death and the nature of the downstream signals by which ER stress ‘convinces’ β-cells to trigger apoptosis. [ABSTRACT FROM AUTHOR]

Background and Objectives Benefits of adopting restrictive guidelines for erythrocyte transfusions are still controversial. The objective of this study was to verify if a very strict guideline could reduce erythrocyte transfusions in preterm infants without adverse outcomes. Materials and Methods Two prospective cohorts of neonates with gestational age < 37 weeks and birth weight < 1500 g were studied. Neonates born in Period 1 were submitted to a strict guideline for erythrocyte transfusions. In Period 2, a new stricter protocol was introduced. Infants of both periods were compared regarding number of transfusions and clinical outcome. Results The median number of transfusions decreased from 2 (1 to 14) in Period 1 to 1 (1–9), P = 0·001, in Period 2. The linear regression multivariate analysis showed that the implementation of the stricter guideline was associated with a reduction in the number of transfusions received by patients by 0·55 (95% confidence interval: –0·08; –1·02) units/patients. Number of apnea episodes, weight at 28 days of life and days of hospital stay were similar in both periods. Intra-hospital death was lower in Period 2. Conclusion A very strict guideline reduced the number of erythrocyte transfusions in preterm infants, without threatening their clinical course. [ABSTRACT FROM AUTHOR]

Background and Purpose: I(Kur) (Ultra-rapid delayed rectifier current) has microM sensitivity to 4-aminopyridine (4-AP) and is an important modulator of the plateau amplitude and action potential duration in canine atria. Kv1.5 encodes I(Kur) and is present in both atria and ventricles in canines and humans. We hypothesized that a similar plateau outward current with microM sensitivity to 4-AP is present in canine ventricle.Experimental Approach: We used established voltage clamp protocols and used 4-AP (50 and 100 microM) to measure a plateau outward current in normal canine myocytes isolated from the left ventricular mid-myocardium.Key Results: Action potential recordings in the presence of 4-AP showed significant prolongation of action potential duration at 50 and 90% repolarization at 0.5 and 1 Hz (P<0.05), while no prolongation occurred at 2 Hz. Voltage clamp experiments revealed a rapidly activating current, similar to current characteristics of canine atrial I(Kur), in approximately 70% of left ventricular myocytes. The IC(50) of 4-AP for this current was 24.2 microM. The concentration of 4-AP used in our experiments resulted in selective blockade of an outward current that was not I(to) or I(Kr). Beta-adrenergic stimulation with isoprenaline significantly increased the 4-AP sensitive outward current density (P<0.05), suggesting a role for this current during increased sympathetic stimulation. In silico incorporation into a canine ventricular cell model revealed selective AP prolongation after current blockade.Conclusions and Implications: Our results support the existence of a canine ventricular plateau outward current sensitive to micromolar 4-AP and its constitutive role in ventricular repolarization. [ABSTRACT FROM AUTHOR]

Background and Purpose: Recent reports suggest that n-3 (omega-3) polyunsaturated fatty acids (PUFAs) may reduce atrial fibrillation (AF). Reduction of the atrial effective refractory period (ERP) is believed to be an important early remodeling event that favors the development and perpetuation of AF. We hypothesized that n-3 PUFAs would attenuate early atrial electrophysiolgical remodeling in a canine model of acute atrial tachypacing.Experimental Approach: Adult dogs of either sex received n-3 PUFAs (n=6), n-6 PUFAs (n=6), or saline (n=6) infused over 1 h. After a stable ERP was established, treatment was initiated concurrently with 6 h of rapid atrial pacing (400 b.p.m.). Serial right atrial ERPs were measured during rapid atrial pacing, and induction of atrial tachyarrhythmias was attempted at the conclusion of each study.Key Results: There was no change in P wave duration or in the PQ, QRS, QT or QTc intervals in any of the treatment groups. N-3 PUFA treatment significantly reduced the shortening of atrial ERP, compared to both control groups (P<0.05). In separate experiments, the same n-3 PUFA infusion was given to dogs remaining in normal sinus rhythm. During sinus rhythm, n-3 PUFA infusion did not alter any electrocardiogram (ECG) parameter or the atrial ERP.Conclusions and Implications: We conclude that acute n-3 PUFA treatment prevents acute atrial electrophysiological remodeling during high rate activity, which may minimize the self-perpetuation of AF. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the frequency and clinical characteristics of ocular complications and their risk factors, as well as autologous serum tears (AST) for the treatment of dry eye in these patients. Data from the files of 124 patients who had undergone allogeneic haematopoietic progenitor cell transplantation (HPCT) were evaluated. In addition, 33 HPCT patients were examined and their data were compared with controls. Analysis of tears and AST was performed. Dry eye manifestation occurred in 32% of patients and was positively correlated with age over 27 years (P=0.05), peripheral blood progenitor cell transplant (P=0.002), chronic graft-versus-host disease (P=0.0027), and chronic or acute myeloid leukaemia (P=0.001). Dry mouth and Schirmer test <5 mm were predictive factors for dry eye in HPCT patients (P=0.002 and odds ratio 3.9 and P=0.007, odds ratio=5.9, respectively). Microbiological analysis revealed that six of 11 AST samples were contaminated after 30 days of use. The present study supports the role of potential risk factors for ocular complications and key elements to detect alterations in the tear film from HPCT patients. In addition, AST contamination must be considered after longer periods of use.Bone Marrow Transplantation (2006) 38, 223–227. doi:10.1038/sj.bmt.1705426; published online 19 June 2006 [ABSTRACT FROM AUTHOR]

The goal of this research was to study the safety and the efficacy of transfusing citrate-phosphate-adenine anticoagulant-preservative (CPDA-1) RBC stored for up to 28 days to reduce donor exposures in premature infants. A prospective randomized two-group study was conducted with very low-birth-weight premature infants that received at least one RBC transfusion during hospital stay. Neonates randomly assigned to Group 1 (26 infants) were transfused with CPDA-1 RBC stored for up to 28 days; those assigned to Group 2 (26 infants) received CPDA-1 RBC stored for up to 3 days. Demographic and transfusion-related data were collected. Neonates from both groups showed similar demographics and clinical characteristics. The number of transfusions per infant transfused was 4·4 ± 4·0 in Group 1 and 4·2 ± 3·1 in Group 2, and the number of donors per infant transfused was 1·5 ± 0·8 (Group 1) and 4·3 ± 3·4 (Group 2), P < 0·001. RBC transfusions containing 29·7 ± 18·3 mmol L−1 of potassium (RBC stored for up to 28 days) did not cause clinical or biochemical changes and reduced donor exposures by 70·2%, compared to transfusions containing 19·8 ± 12·3 mmol L−1 of potassium (RBC stored for up to 3 days), P < 0·001. In conclusion, RBC stored for up to 28 days safely reduced donor exposures in premature infants. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: To assess the involvement of the AGE-specific receptor (AGER, also known as RAGE) axis and nuclear factor kappa-B (NFKB, also known as NF-kappaB) activation in the development of lacrimal gland and tear film dysfunction in diabetes, the present study evaluated: (1) lacrimal gland and tear film alterations in diabetic rats; and (2) the expression of AGE, AGER and NFKB in ocular tissues of normoglycaemic and diabetic rats. Materials and Methods: Diabetes was induced in male Wistar rats with intravenous streptozotocin. Tear secretion parameters were measured and NFKB expression was evaluated in lacrimal glands of control and diabetic rats by western blot. Immunohistochemistry with confocal microscopy was used to assess AGE, AGER and NFKB expression in lacrimal glands of both groups. Results: Lacrimal gland weight and tear film volume were lower in diabetic than in control rats (p=0.01 and 0.02, respectively). IL1B and TNF concentrations in tears were higher in diabetic than in control rats (p=0.007 and 0.02, respectively). NFKB protein was identified in rat cornea, conjunctiva and lacrimal glands. AGE, AGER and NFKB expression were greater in lacrimal glands of diabetic than in those of control rats. Conclusions/interpretation: Diabetes induces significant alterations in rat lacrimal gland structure and secretion. The higher expression of AGE, AGER and NFKB in lacrimal glands of diabetic rats suggests that these factors are involved in signalling and in subsequent inflammatory alterations related to dry eye in diabetes mellitus. [ABSTRACT FROM AUTHOR]

This paper describes the MAGI (microscope-assisted guided interventions) augmented-reality system, which allows surgeons to view virtual features segmented from preoperative radiological images accurately overlaid in stereo in the optical path of a surgical microscope. The aim of the system is to enable the surgeon to see in the correct 3-D position the structures that are beneath the physical surface. The technical challenges involved are calibration, segmentation, registration, tracking, and visualization. This paper details our solutions to these problems. As it is difficult to make reliable quantitative assessments of the accuracy of augmented-reality systems, results are presented from a numerical simulation, and these show that the system has a theoretical overlay accuracy of better than 1 mm at the focal plane of the microscope. Implementations of the system have been tested on volunteers, phantoms, and seven patients in the operating room. Observations are consistent with this accuracy prediction. [ABSTRACT FROM AUTHOR]

Conflicting data are available concerning left ventricular (LV) function in patients after total correction of tetralogy of Fallot (TOF). The response to afterload stress determined by methoxamine challenge and the peak systolic blood pressure-end-systolic volume relationship were evaluated echocardiographically in 20 postoperative TOF patients (age range 9 to 15 years, mean 12±2). All patients were without significant residual shunts or pulmonary stenosis. Results were compared with those in 10 control subjects (age range 9 to 15 years, mean 11±2). The TOF group had higher mean end- diastolic (76·9±14·4 vs 66·2±7·2 ml. m P<0·05) and mean end-systolic (36·7±8 vs 29·6±3·9 ml. m P<0·05 volumes than controls. Stroke volume index (SVI) and LV ejection fraction were similar in the two groups. In normal subjects, mnethoxamine caused a decrease in SVI in seven Out of 10 patients and a mild increase in three; the mean value of SVI at rest was not significantly different from the mean value at peak pressor effect (36·5±4·4 vs 35·9±4·0 ml. m, P=NS). In the TOF group, methoxamine induceda reduction in SVI in all patients, the mean value of SVl at peak pressor effect was significantly lower than the mean value at rest (31·3±5·4 vs 40·2±6·9 ml. m P<0·001). Ejection fraction decreased in both groups with the afterload challenge, but in the TOF patients the reduction was significantly higher than in the normal subjects (from 53±4 to 38±5% vs from 55±3 to 49±3%, P<0·001). Peak systolic blood pressure-end- systolic volume relationships were constructed. The slope (m) of the relationship was significantly lower in the TOF group than in the control subjects (2·85±0·77 vs 6·21+0·58, p<0·001);in the TOE group m was below the 95% confidence limit in all studied patients. There was a significant correlation between aortic oxygen saturation preoperatively and the slope of the peak systolic pressure-end-systolic volume relation. Thus, LV function after successful total correction of TOFmay be abnormal, with larger than normal LV size and decreased contractile function. [ABSTRACT FROM PUBLISHER]

Conflicting data are available concerning left ventricular (LV) function in patients after total correction of tetralogy of Fallot (TOF). The response to afterload stress determined by methoxamine challenge and the peak systolic blood pressure-end-systolic volume relationship were evaluated echocardiographically in 20 postoperative TOF patients (age range 9 to 15 years, mean 12±2). All patients were without significant residual shunts or pulmonary stenosis. Results were compared with those in 10 control subjects (age range 9 to 15 years, mean 11±2). The TOF group had higher mean end- diastolic (76·9±14·4 vs 66·2±7·2 ml. m P<0·05) and mean end-systolic (36·7±8 vs 29·6±3·9 ml. m P<0·05 volumes than controls. Stroke volume index (SVI) and LV ejection fraction were similar in the two groups. In normal subjects, mnethoxamine caused a decrease in SVI in seven Out of 10 patients and a mild increase in three; the mean value of SVI at rest was not significantly different from the mean value at peak pressor effect (36·5±4·4 vs 35·9±4·0 ml. m, P=NS). In the TOF group, methoxamine induceda reduction in SVI in all patients, the mean value of SVl at peak pressor effect was significantly lower than the mean value at rest (31·3±5·4 vs 40·2±6·9 ml. m P<0·001). Ejection fraction decreased in both groups with the afterload challenge, but in the TOF patients the reduction was significantly higher than in the normal subjects (from 53±4 to 38±5% vs from 55±3 to 49±3%, P<0·001). Peak systolic blood pressure-end- systolic volume relationships were constructed. The slope (m) of the relationship was significantly lower in the TOF group than in the control subjects (2·85±0·77 vs 6·21+0·58, p<0·001);in the TOE group m was below the 95% confidence limit in all studied patients. There was a significant correlation between aortic oxygen saturation preoperatively and the slope of the peak systolic pressure-end-systolic volume relation. Thus, LV function after successful total correction of TOFmay be abnormal, with larger than normal LV size and decreased contractile function. [ABSTRACT FROM PUBLISHER]