To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Litter size reduction can induce early overnourishment, being an attractive experimental model to study short- and long-term consequences of childhood obesity. Epidemiological data indicate sex differences regarding cardiometabolic disorders and hypertrophic cardiomyopathy. The present study aimed to describe biometric, nutritional and cardiovascular changes related to neonatal overweight promoted by litter size reduction in young and adult Wistar rats of both sexes. Litter adjustment to eight or four pups/mother (1:1 male-to-female ratio) gave, respectively, control and overweight groups. Body mass, food intake, haemodynamic and echocardiographic parameters and cardiorespiratory capacity were evaluated at postnatal days 30 and 150. Diminished litters were correlated with higher body mass and weight gain (12 %) during lactation, validating the experimental model of neonatal overweight. Soon after weaning male (16 %) and female (25 %) offspring of these litters presented a lower food intake than their respective control, without differences in body mass. Adult males from reduced litters presented higher abdominal circumference (7 %), systolic blood pressure (10 %), interventricular septum thickness (15 %) and relative wall thickness (15 %) compared with their respective control. Rats' performance on the maximal effort ergometer test was not affected by neonatal overweight. Data suggest the occurrence of catch-down growth and hypophagia in male and female rats submitted to neonatal overweight. However, only male rats presented haemodynamic and cardiac structural changes. These findings are crucial to personalised/gender medicine.
The effects of cold atmospheric plasma (CAP) of dielectric barrier discharges on the wettability, imbibition and germination of Leucaena leucocephala were investigated. It was established that CAP treatment markedly hydrophilized the seed coat, especially at longer treatment times. From the profile of the imbibition curve and visual observation, it was possible to verify that there are two resistance barriers to water penetration: integument surface and region of the macrosclereid cell wall (light line). Although the plasma interacts only in the integument, increasing the density of hydrophilic sites increases the capacity of water absorption, producing enough driving force to overcome the second resistance barrier. The existence of these two barriers changes the three-phase pattern generally observed during seed germination. Despite an increase in imbibition, the plasma treatment conditions used in this work, were not enough to overcome completely the dormancy barrier.
Tuberous sclerosis complex is a rare genetic disorder leading to the growth of hamartomas in multiple organs, including cardiac rhabdomyomas. Children with symptomatic cardiac rhabdomyoma require frequent admissions to intensive care units, have major complications, namely, arrhythmias, cardiac outflow tract obstruction and heart failure, affecting the quality of life and taking on high healthcare cost. Currently, there is no standard pharmacological treatment for this condition, and the management includes a conservative approach and supportive care. Everolimus has shown positive effects on subependymal giant cell astrocytomas, renal angiomyolipoma and refractory seizures associated with tuberous sclerosis complex. However, evidence supporting efficacy in symptomatic cardiac rhabdomyoma is limited to case reports. The ORACLE trial is the first randomised clinical trial assessing the efficacy of everolimus as a specific therapy for symptomatic cardiac rhabdomyoma.
ORACLE is a phase II, prospective, randomised, placebo-controlled, double-blind, multicentre protocol trial. A total of 40 children with symptomatic cardiac rhabdomyoma secondary to tuberous sclerosis complex will be randomised to receive oral everolimus or placebo for 3 months. The primary outcome is 50% or more reduction in the tumour size related to baseline. As secondary outcomes we include the presence of arrhythmias, pericardial effusion, intracardiac obstruction, adverse events, progression of tumour reduction and effect on heart failure.
ORACLE protocol addresses a relevant unmet need in children with tuberous sclerosis complex and cardiac rhabdomyoma. The results of the trial will potentially support the first evidence-based therapy for this condition.
Both transposition of the great arteries (TGA) previously submitted to a Senning/Mustard procedure and congenitally corrected TGA (cc-TGA) have the systemic circulation supported by the morphological right ventricle, thereby rendering these patients to heart failure events risk. The aim of this study was to evaluate cardiopulmonary exercise test parameters for stratifying the risk of heart failure events in TGA patients.
Retrospective evaluation of adult TGA patients with systemic circulation supported by the morphological right ventricle submitted to cardiopulmonary exercise test in a tertiary centre. Patients were followed up for at least 1 year for the primary endpoint of cardiac death or heart failure hospitalisation. Several cardiopulmonary exercise test parameters were analysed as potential predictors of the combined endpoint and their predictive power were compared (area under the curve).
Cardiopulmonary exercise test was performed in 44 TGA patients (8 cc-TGA), with a mean age of 35.1 ± 8.4 years. The primary endpoint was reached by 10 (22.7%) patients, with a mean follow-up of 36.7 ± 26.8 months. Heart rate at anaerobic threshold had the highest area under the curve value (0.864), followed by peak oxygen consumption (pVO2) (0.838). Heart rate at anaerobic threshold ≤95 bpm and pVO2 ≤20 ml/kg/min had a sensitivity of 87.5 and 80.0% and a specificity of 82.4 and 76.5%, respectively, for the primary outcome.
Heart rate at anaerobic threshold ≤95 bpm had the highest predictive power of all cardiopulmonary exercise test parameters analysed for heart failure events in TGA patients with systemic circulation supported by the morphological right ventricle.
The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favourable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of global (astrospheric), and local (atmospheric and surface) environments of exoplanets in the habitable zones (HZs) around G-K-M dwarf stars including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favourable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro)physical, chemical and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the HZ to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field in light of presentations and discussions during the NASA Nexus for Exoplanetary System Science funded workshop ‘Exoplanetary Space Weather, Climate and Habitability’ and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology.
Intake in sugar-rich diets can be limited either via rumen fill or excessive rumen fermentation and source of non-fibre carbohydrate (NFC) in the diet can affect both factors. The aim of the current study was to quantify the effect of partially replacing ground maize (GM) with steam-rolled maize (SRM) or pelleted citrus pulp (PCP) at two concentrate levels in sugarcane-based diets on digestibility, rumen ecosystem and metabolism of Nellore steers. Six rumen-cannulated steers were assigned to a 6 × 6 Latin square, replicated in time, in a 2 × 3 factorial arrangement of treatments with two levels of concentrate (600 or 800 g concentrate/kg dry matter [DM]) and three NFC sources. Each steer within a period was considered an experimental unit. Feeding more concentrate increased total tract digestibility of organic matter and decreased fibre intake and passage rate. It also reduced rumen populations of Fibrobacter succinogenes and Streptococcus bovis and increased Ruminococcus flavefaciens. Substituting PCP for GM increased rumen pH, acetic acid and organic matter digestibility. Feeding PCP also reduced R. flavefaciens and R. amylophilus rumen populations. Substituting SRM for GM increased starch digestibility and rumen propionic acid, but decreased rumen ammonia concentration. Feeding SRM increased rumen populations of Megasphaera elsdenii with the high-concentrate diet but reduced Ruminococcus albus populations at both concentrate levels. In conclusion, partial replacement of GM by PCP decreased intake in sugar-rich diets, while increasing total tract neutral detergent fibre digestibility. Replacement of GM with SRM increases rumen fermentation and total tract digestibility of starch.
The aim of this study was to establish a functional freezing–thawing protocol for epididymal sperm of collared peccaries (Pecari tajacu L., 1758) by comparing different extenders. The epididymal sperm from 12 sexually mature males was recovered by retrograde flushing using Tris-based or coconut water-based (ACP®-116c) extenders. After initial evaluation, samples were diluted and frozen with the same extenders to which 20% egg yolk and 6% glycerol were added. After 2 weeks, thawing was performed at 37°C/60 s and sperm motility, vigour, morphology, functional membrane integrity, sperm viability, sperm plasma membrane integrity, and a computer-assisted semen analysis (CASA) were assessed. In addition, to evaluate the survival of frozen–thawed sperm, a thermal resistance test (TRT) was executed. Samples preserved using Tris were in better condition compared with those preserved using ACP®, showing higher values for most assessments performed, including CASA and the TRT (P<0.05). After determining Tris to be the better of the two extenders, additional samples were thawed using different thawing rates (37°C/60 s, 55°C/7 s, 70°C/8 s). Sperm thawed at 37°C/60 s had the greatest preservation (P<0.05) of viability (54.1 ± 5.9%) and functional membrane integrity (43.2 ± 5.4%), and had higher values for various CASA parameters. In conclusion, we suggest the use of a Tris-based extender added to egg yolk and glycerol for the cryopreservation of epididymal sperm obtained from collared peccaries. In order to achieve better post-thawing sperm quality, we suggest that samples should be thawed at 37°C/60 s.
Several studies have shown that maternal low-protein (LP) diet induces detrimental effects in cardiovascular system and oxidative stress in male animals. Additional studies suggested that female has lower incidence of cardiovascular disease. However until present data, the possible effects of estradiol on the undernutrition during gestational and lactation periods are not discussed. The present study was conducted to evaluate the effects of a maternal LP diet during gestational and lactation period on oxidative balance in the female rat hearts ventricles at two ages. Dams were fed with normal protein (NP) or a LP diet during the gestational and lactation period, and their female offspring were divided into age groups (22 or 122 days, corresponding to a low or high estrogen level) composing four experimental groups. Evaluating the nutritional effect showed an increase in oxidative stress biomarkers and decrease in enzymatic defense in LP-22D compared with NP-22D. In contrast, no changes were observed in malondialdehyde and carbonyls, but an increase in glutathione-S-transferase (GST) activity in the LP-122D compared with NP-122D. The global oxy-score in the LP-22D group indicated a predominance of oxidative damage when compared with NP-22D, while in LP-122D group the global oxy-score was restored to NP-122D levels. Evaluating the estradiol effect, our data show a significant decrease in oxidative stress with increase in CAT and GST activity, associated with increase in intracellular thiols. Our data suggest that in situation with low levels of estradiol, hypoproteic diet during gestation and lactation period has detrimental effects on heart, however when estradiol levels raise, the detrimental effects induced are mitigated.
Three assays were performed. In assay 1, oocytes harvested during the winter months were subjected to kinetic heat shock by stressing the oocytes at 39.5°C (HS1) or at 40.5°C (HS2) for either 6, 12, 18 or 24 h and then matured at control temperature (38.5°C). The nuclear maturation rates (NMR) of all oocytes were recorded after 24 h. In assay 2, oocytes collected year-round maturated, were implanted via in vitro fertilization (IVF) and developed for 9 days. Gene expression analysis was performed on target genes (Cx43, CDH1, DNMT1, HSPA14) with reference to the two housekeeping genes (GAPDH and SDHA) in embryos. Similarly, in assay 3, genetic analysis was performed on the embryos produced from heat-stressed oocytes (from HS1 and HS2). In assay 1, the duration of heat stress resulted in a significant decline in NMR (P < 0.05) with HS1 for maturated oocytes at 86.4 ± 4.3; 65.5 ± 0.7; 51.3 ± 0.9; 38.1 ± 1.9 and 36.3 ± 0.9, for control, 6 h, 12 h, 18 h and 24 h, respectively. For assays 2 and 3, results demonstrated that DNMT1, Cx43 and HSPA14 were down-regulated in the embryos produced in the warm with respect to the cold months (P < 0.05). A constant up- and down-regulation of DNMT1 and HSPA14 genes were observed in both HS-treated samples. Also, an inconsistent pattern of gene expression was observed in Cx43 and CDH1 genes (P < 0.05). Targeted gene expression was aberrant in embryo development, which can provide evidence on early embryo arrest and slowed embryo development.
Human oocyte dysmorphisms attain a large proportion of retrieved oocytes from assisted reproductive technology (ART) treatment cycles. Extracytoplasmic defects involve abnormal morphology of the zona pellucida (ZP), perivitelline space and first polar body. The aim of the present study was to describe a novel dysmorphism affecting the ZP, indented ZP. We also evaluated the clinical, embryological and ultrastructural features of these cases. We evaluated all ART treatment cycles during 7 consecutive years and found 13 treatment cycles (six patients) with all oocytes presenting an indented ZP. In addition, these oocytes presented total or partial absence of the perivitelline space, absence of resistance to ZP and oolemma penetration during microinjection, and low ooplasm viscosity during aspiration. This novel described dysmorphism was recurrent and attained all oocytes in three cases that had more than one treatment cycle. When compared with controls, data showed significant low oocyte maturity (42% versus 81.6%) and high cycle cancellation (30.8% versus 8.5%) rates, normal degeneration (3.4% versus 6.3%) and fertilization rates (69% versus 69.5%), and low pregnancy (15.4% versus 33.3%) and live-birth delivery (7.7% versus 27.7%) rates per cycle. Ultrastructure analysis revealed a zona pellucida structure with large empty electrolucent regions, an outer ZP layer with an indented surface with protuberances and a thick inner ZP that obliterated the perivitelline space. There was evidence of exocytosis of ZP material by the oocyte. In conclusion, oocytes with this novel described dysmorphism (indented ZP) are associated with low maturity, pregnancy and live-birth delivery rates.
Civil engineering is a branch of science that covers a broad range of areas where experimental procedures often plays an important role. The research in this field is usually supported by experimental structures able to test physical and mathematical models and to provide measurement results with acceptable accuracy. To assure measurement quality, a metrology probabilistic approach can provide valuable mathematical and computational tools especially suited to the study, evaluation and improvement of measurement processes in its different components (modeling, instrumentation performance, data processing, data validation and traceability), emphasizing measurement uncertainty evaluation as a tool to the analysis of results and to promote the quality and capacity associated with decision-making. This paper presents some of the research held by the metrology division of the Portuguese civil engineering research institutes, focused on the contribution of measurement uncertainty studies to a variety of frameworks, such as testing for metrological characterization and physical and mathematical modeling. Experimental data will be used to illustrate practical cases.
The Neotropics house two guilds of large arboreal vertebrate seed predators: parrots and the pitheciin primates. Both have diets dominated by immature fruits. The possibility of members of the Pitheciinae (genera Cacajao, Chiropotes and Pithecia) acting as occasional seed dispersers has been mooted, but not experimentally shown. We combined primate behavioural data and seed germination data from three separate field studies in the Brazilian states of Amazonas and Pará to analyse patterns of post-consumption seed survivorship for seeds discarded by three pitheciin species (Cacajao melanocephalus ouakary, Chiropotes chiropotes and Chiropotes albinasus). We then calculated the frequency of dispersal events for four species eaten by C. m. ouakary. All three primate species dropped intact seeds while feeding, and 30.7% of 674 dropped seeds germinated ex situ. Undamaged seeds from unripe and ripe samples germinated (29.3% and 42.7%, respectively), and all three primate species carried some fruits up to 20 m from the parent tree before consuming them. Potential seed-dispersal events varied from 1 (Macrolobium acaciifolium) per fruiting cycle to more than 6500 (Duroia velutina), suggesting that there are differences in dispersal potential. In summary, although they are highly specialized seed predators, these primates may also act as important dispersers for some plant species, and effective dispersal is not restricted to ripe fruits, as immature fruits removed from a tree may continue to mature and the seeds later germinate, a much-neglected aspect of dispersal ecology. The possibility that similar events occur in parrots should be experimentally investigated.
Spermatogenesis is a complex process of cell proliferation, meiosis and differentiation. In order to determine the genetic mechanisms that control this process we need to develop adequate methodologies for the purification of stage-specific germ cells. In this study we aim to evaluate four markers (c-kit, oct-4, Integrin α6 and Integrin β1), used to isolate spermatogonial stem cells in mammals, as possible markers to isolate/sort testicular adult stem and progenitor cells in humans.
The occurrence of dolphins in the Belém area, northern Brazil, has been poorly surveyed. In addition, there has been much speculation on the identity of cetaceans inhabiting these brackish waters. Vantage point observations conducted from September 2008 to October 2010 resulted in the observation of 44 groups of dolphins and 79 individuals. Among these, 56 were Inia geoffrensis (71%) and 23 Sotalia. In addition, 21 boat transects were conducted and recorded 50 individuals in 19 sightings. Among sighted during transects 36 were Sotalia (72%) and 14 were Inia. In both observation methods, Tasco Offshore binoculars were used and size and group composition and behaviour (feeding, resting, socializing, travelling and not identified) were recorded. All the categories of behaviour were recorded for Inia and Sotalia, except resting. The Inia group size ranged from one to four individuals, the solitary ones prevailing (57% in vantage point and 67% in boat surveys). Groups ranging from one to seven Sotalia dolphins were registered, in both observation methods. Boto calves were observed in September 2008 and 2009, and February 2010. In April 2010 two botos were sighted in courtship behaviour. Sotalia calves were found in March, May and December 2009. Botos frequently came closer to the right river margin, often entering the Igarapé do Tucunduba, usually in feeding behaviour. On the other hand, Sotalia was sighted in the main channel, or closer to the left margin, opposite to the observation point. Sotalia were observed in the rainy season, except for three sightings in the dry season.
In testis we find mainly PPP1gamma2 isoform. We hypothesize that in different cell types we can find different regulatory subunits that may constitute targets for therapeutics of diseases such as male infertility, cancer and Alzheimer's disease. We identified a novel alternative splicing isoform of IIIG9 in testis, a known regulator of PPP1, IIIG9sT, and the aim of this study was its further characterization. We used a specific antibody for IIIG9sT in order to characterize its localization in bovine sperm cells. We also transfected IIIG9sT-GFP construct in mouse spermatogonia cells (GC-1 cells) and we used specific antibodies for each PPP1 isoform for the colocalization studies. We observed them under a fluorescent microscope and a LSM and quantified a high co-localization with PPP1gamma1 and 2 isoforms.
Protein phosphatase 1 (PPP1) is the PPP most ubiquitous and each isoform interact with regulatory subunits that may be responsible for their subcellular localization. We identified PPP1R15B, C1ORF71 as novel regulators and the aim of this study was their further characterization in carcinoma cells. We analysed localization of each regulator in MDA-MB-468 cells and we transfected with constructs that we made with each as a GFP-fusion protein. For PPP1 cellular localization we used specific antibodies for each isoform. We observed the cells under a fluorescent microscope and LSM and we quantified co-localization. We found a high overlap coefficient of both the novel proteins with PPP1alpha and PPP1gamma1. We propose a model in which PPP1 regulator interacts with one or two regulatory subunits that may be used as target for therapeutic strategies.
The magnetoresistive behavior of granular thin films prepared by Fe and Co implantation in Ag thin films is reported. Ag thin films (∼2000Å) were implanted with Fe or Co at fluences up to 8×1016 at./cm2. The magnetoresistive response obtained after implantation was found to increase with the implanted fluence. A further increase by a factor of 3–4 can be achieved annealing the films in a conventional furnace at 620 K under vacuum. The best value of the magnetoresistance obtained so far is 9% at 10 K for a film implanted with Co at a fluence of 8×1016 at./cm2.
Email your librarian or administrator to recommend adding this to your organisation's collection.