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The mechanisms involved in kidney disturbances during development, induced by vitamin D3 deficiency in female rats, that persist into adulthood were evaluated in this study. Female offspring from mothers fed normal (control group, n=8) or vitamin D-deficient (Vit.D-, n=10) diets were used. Three-month-old rats had their systolic blood pressure (SBP) measured and their blood and urine sampled to quantify vitamin D3 (Vit.D3), creatinine, Na+, Ca+2 and angiotensin II (ANGII) levels. The kidneys were then removed for nitric oxide (NO) quantification and immunohistochemical studies. Vit.D- pups showed higher SBP and plasma ANGII levels in adulthood (P<0.05) as well as decreased urine osmolality associated with increases in urinary volume (P<0.05). Decreased expression of JG12 (renal cortex and glomeruli) and synaptopodin (glomeruli) as well as reduced renal NO was also observed (P<0.05). These findings showed that renal disturbances in development in pups from Vit.D- mothers observed in adulthood may be related to the development of angiogenesis, NO and ANGII alterations.
Here we evaluated the effect of fermented milk supplemented with whey protein (approximately 80 % protein), probiotic (Bifidobacterium animalis subsp. lactis BB12) and pomegranate juice (Punica granatum L.) on the physical performance, intestinal motility and villi structure, inflammatory markers and intestinal microbiota of rats under high-intensity acute exercise. In all, twenty-four Wistar rats were separated into groups: control (Ctrl), supplemented (Supp), exercised (Exe) and exercised and supplemented (Exe+Supp). Rats in the Supp groups received fermented milk during 6 weeks by oral administration. At the end of the supplementation period, the Exe groups were submitted to high-intensity acute exercise on a treadmill. We found that intense acute exercise caused changes in the intestinal villi interspace, changes in the proportion of Lactobacillus species and an increase in Clostridium species, as well as a decrease in intestinal motility. Supplementation increased intestinal motility, and maintained the intestinal villi interspace and the natural microbiota proportions of the exercised rats. Physical performance was not improved by fermented milk supplementation. We conclude that the fermented milk containing whey protein, B. animalis (BB12) and pomegranate juice can re-establish intestinal microbiota and protect the animals from the undesirable effects of intense acute exercise.
Non-typhoidal Salmonella is an important burden, particularly in developing countries of the African region. We report for the first time in Angola, a sub-Saharan African country with commercial/travel relationships with Europe, an unexpectedly high occurrence of Salmonella (n = 12/63, 19%) from a high diversity of sources, particularly farm and wild animals. The detection of diverse serotypes (n = 12), involving putative new S. enterica subsp. salamae serotypes, is also of note, reinforcing the need for a comprehensive surveillance in Angola critical to identify animal/food/environmental sources of salmonellosis with impact on animal health, local people, tourists and exported products.
Extreme solar-terrestrial events are those in which very energetic solar ejections hit the earth?s magnetosphere, causing intense energization of the earth?s ring current. Statistically, their occurrence is approximately once per Gleissberg solar cycle (70-100yrs). The solar transient occurred on July, 23rd (2012) was potentially one of such extreme events. The associated coronal mass ejection (CME), however, was not ejected towards the earth. Instead, it hit the STEREO A spacecraft, located 120 degrees away from the Sun-Earth line. Estimates of the geoeffectiveness of such a CME point to a scenario of extreme Space Weather conditions. In terms of the ring current energization, as measured by the Disturbance Storm-Time index (Dst), had this CME hit the Earth, it would have caused the strongest geomagnetic storm in space era.
Some key physical processes that impact the evolution of Earth's atmosphere on time-scale from days to millennia, such as the EUV emissions, are determined by the solar magnetic field. However, observations of the solar spectral irradiance are restricted to the last few solar cycles and are subject to large uncertainties. We present a physics-based model to reconstruct short-term solar spectral irradiance (SSI) variability. The coronal magnetic field is estimated to employ the Potential Field Source Surface extrapolation (PFSS) based on observational synoptic charts and magnetic flux transport model. The emission is estimated to employ the CHIANTI atomic database 8.0. The performance of the model is compared to the emission observed by TIMED/SORCE.
The density and temperature profiles in the solar corona are complex to describe, the observational diagnostics is not easy. Here we present a physics-based model to reconstruct the evolution of the electron density and temperature in the solar corona based on the configuration of the magnetic field imprinted on the solar surface. The structure of the coronal magnetic field is estimated from Potential Field Source Surface (PFSS) based on magnetic field from both observational synoptic charts and a magnetic flux transport model. We use an emission model based on the ionization equilibrium and coronal abundances from CHIANTI atomic database 8.0. The preliminary results are discussed in details.
To evaluate the clinical and histopathological factors affecting the prognosis of patients with squamous cell locoregional advanced laryngeal cancer.
A retrospective chart review was conducted of 121 patients with locoregional advanced laryngeal cancer, primarily treated with surgery from 2007 to 2011. Disease-free survival and overall survival rates were analysed as oncological outcomes. Prognostic variables, namely gender, pharyngeal invasion, pathological assessment of tumour and nodal stage, adjuvant therapy, margin status, nodal extracapsular extension, tumour differentiation, lymphovascular and perineural invasion, and predominant growth pattern, were also analysed.
One-year and three-year disease-free survival rates were 81.3 per cent and 63.5 per cent, respectively. One-year and three-year overall survival rates were 88.3 per cent and 61.4 per cent, respectively. Multivariate analysis showed that nodal extracapsular extension (p < 0.05) and an infiltrative growth pattern (p < 0.05) were associated with disease progression. Nodal extracapsular extension (p < 0.05) was associated with higher mortality.
Nodal extracapsular extension and an infiltrative growth pattern were the main prognostic factors in locoregional advanced laryngeal cancer. The presence of pharyngeal invasion, pathologically confirmed node-positive stage 2–3 disease, close or microscopic positive margins, and lymphovascular and perineural invasion have a negative impact on prognosis.
The magnetic flux emergence can help understand the physical mechanism responsible for solar atmospheric phenomena. Emerging magnetic flux is frequently related to eruptive events, because when emerging they can reconnected with the ambient field and release magnetic energy. We will use a physic-based model to reconstruct the evolution of the solar emission based on the configuration of the photospheric magnetic field. The structure of the coronal magnetic field is estimated by employing force-free extrapolation NLFFF based on vector magnetic field products (SHARPS) observed by HMI instrument aboard SDO spacecraft from Sept. 29 (2013) to Oct. 07 (2013). The coronal plasma temperature and density are described and the emission is estimated using the CHIANTI atomic database 8.0. The performance of the our model is compared to the integrated emission from the AIA instrument aboard SDO spacecraft in the specific wavelengths 171Å and 304Å.
To conduct a systematic review aimed at identifying and characterizing the experience-based household food security scales and to synthesize their psychometric properties.
Search in the MEDLINE, LILACS and SciELO databases, using the descriptors (‘food insecurity’ OR ‘food security’) AND (‘questionnaires’ OR ‘scales’ OR ‘validity’ OR ‘reliability’). There was no limitation on the period of publication. All articles had their titles and abstracts analysed by two reviewers. The studies of interest were read in their entirety and the relevant information extracted using a standard form.
The initial bibliographic search identified 299 articles. Of these, the 159 that seemed to meet the criteria for inclusion were read fully. After consultation of the bibliographic references of these articles, twenty articles and five documents were added, as they satisfied the previously determined criteria for inclusion. Twenty-four different instruments were identified; all were brief and of easy application. The majority were devised in the USA. Forty-seven references reported results of psychometric studies. The instruments that presented the highest number of psychometric studies were the Core Food Security Measurement/Household Food Security Survey Module (CFSM/HFSSM) and the Self-Perceived Household Food Security Scale.
There are a number of structured scales available in the literature for characterization of household food insecurity. However, despite some psychometric studies already existing about the majority of the instruments, it is observed that, except for the studies of the CFSM/HFSSM, these are still restricted to appraisal of a few aspects of reliability and validity.
The aim of this study was to investigate the effect of fasting and exogenous insulin administration on the expression of growth hormone receptor (GHR) and IGF-I mRNA in the pre-ovulatory follicle of ewes. Fifteen ewes received an intravaginal progesterone releasing device that was removed 6 days later (day of removal = day 0). On day −2, the ewes were divided into three groups: (i) fasting group (n = 5) that was fasted from day −2 to day 2; (ii) control group (n = 5) that received a maintenance diet; and (iii) insulin group (n = 5) that received insulin injections (0.25 IU/kg) every 12 h from day −2 to day 2 under the same diet as the control group. Follicular samples were obtained on day 2. Fasting increased plasma non-esterified fatty acids concentrations from day −1 to day 2 (P < 0.001). There was no difference (P > 0.05) in the number of follicles, although there was a tendency for an increase in the pre-ovulatory follicle diameter for the insulin group in comparison to the control group (P = 0.12). Thecal GHR mRNA expression was very low and was considered insignificant. Moreover, granulosa cells GHR mRNA expression increased (P < 0.05) in the insulin group. Expression of IGF-I mRNA was not different among groups in both tissues. In conclusion, insulin administration increases GHR mRNA but not IGF-I mRNA expression in granulosa cells of the pre-ovulatory follicle. However, fasting did not change the pattern of GHR/IGF-I mRNA expression in the pre-ovulatory follicle.
Delta doping (paused growth doping) was investigated as an alternative to uniformly distributing the dopant in the nitride semiconductor layer. In this work, delta doped layers were produced in MOVPE-grown AlGaN and GaN layers at a susceptor temperature of 1220°C by turning off the group III precursors (TMG and TMA) and introducing into the reactor a silicon precursor Si2H6 (disilane) for a fixed period (pause time) before growth was restarted. The compositional and electrical properties as a function of aluminum content and dopant flux were investigated for nitride layers on 2 inch c-plane sapphire substrates. Secondary ion mass spectroscopy (SIMS) measurements revealed a sharp silicon peak with a FWHM of 5.7 ± 0.6 nm for an Al0.25Ga0.75N sample and 10.0 ± 0.6 nm for a GaN sample with sheet charges of 7.9×1012 cm−2 and 9.9×1012 cm−2,respectively. Room temperature Hall mobility as high as 265 cm2 V−1s−1 for a sheet charge 7.9×1012 cm−2 was demonstrated for delta doped Al0.25Ga0.75N layers, but the mobility enhancement saturated and then decreased with increasing sheet charge. Room temperature sheet charge increased with increasing dopant flux for delta-doped AlGaN and GaN layers. Sheet charge density as high as 2.2×1013 cm−2 and 1.3×1013 cm−2 was measured at room temperature for Al0.25Ga0.75N and GaN delta doped layers, respectively. Under identical doping conditions, the Hall sheet charge of the delta doped Al0.25Ga0.75N layer was approximately half as large as GaN layers. The impurity and electrical characteristics of the delta doped layers are further discussed.
In this paper, we report the electrical and optical characteristics of Si delta-doped AlGaN cladding layers, p-cladding structure optimization and the impact on the efficiency of 340nm AlGaN UV LEDs. Compared to the uniformly doped n-AlGaN layer, adding Si Δ-doping layers reduced the sheet resistance by improving both the Hall mobility and carrier concentration. Increasing the number of Si Δ-doped layers further lowered the sheet resistance without cracking the material. The Δ-doped layers in n-Al0.3Ga0.7N improved the optical properties by enhancing near band edge emission as much as 2-fold relative to deep level emission. Additionally, Δ-doping in n-AlGaN layers had no detrimental effect on the optical transparency of the LEDs. The p-cladding layer was found to have a strong absorption at 340nm. Reducing the p-GaN cap layer from 35nm to 10nm tripled the light emission intensity. By optimizing the n- and p-AlGaN cladding layers, a highly efficient UV LED at 340nm was achieved with 1mW output under 800mA/mm2 DC drive current.
The present review has the objective of summarising chronobiological aspects of shift work and obesity. There was a systematic search in PubMed databases, using the following descriptors: shift work; obesity; biological clock. Shift work is extremely frequent in several services and industries, in order to systematise the needs for flexibility of the workforce, necessary to optimise productivity and business competitiveness. In developing countries, this population represents a considerable contingent workforce. Recently, studies showed that overweight and obesity are more prevalent in shift workers than day workers. In addition, the literature shows that shift workers seem to gain weight more often than those workers submitted to a usual work day. In conclusion, there is considerable epidemiological evidence that shift work is associated with increased risk for obesity, diabetes and CVD, perhaps as a result of physiological maladaptation to chronically sleeping and eating at abnormal circadian times. The impact of shift work on metabolism supports a possible pathway to the development of obesity and its co-morbities. The present review demonstrated the adverse cardiometabolic implications of circadian misalignment, as occurs chronically with shift workers.
The Asian clam Corbicula fluminea is one of the most invasive species in freshwater aquatic ecosystems. The rapid growth,
earlier sexual maturity, short life span, high fecundity and its association with human activities makes C. fluminea a
non-indigenous invasive species likely to colonize new environments. This species, originally distributed in Asiatic ecosystems,
is now a common inhabitant of American and European freshwater habitats. The present paper reviews the information related to
the life cycle, ecology and potential ecological and economic impacts caused by C. fluminea in the invaded habitats.
Furthermore, this paper also proposed future works that may be implemented in order to increase our general knowledge about
the ecology of this bivalve.
This study evaluated the status of the Asian clam Corbicula fluminea (Müller, 1774) in the River Lima estuary (Portugal),
which it first invaded in 2002. During the summers of 2004 and 2005, spatial and temporal variations in the abundance, biomass
and population structure of C. fluminea were investigated in this estuary. This species was present in a limited intertidal area of
the estuary and was rarely found in the subtidal zone. Its abundance and biomass were considerably lower than those found in
other estuarine systems. Based on these studies it appears that salinity fluctuations and possibly other factors such as nutrients
and environmental contaminants are keeping this invasive species from reaching its full potential. Given the lower abundance
and biomass recorded and the restrict distribution of the species in this estuary, the eradication of this nonindigenous invasive
species is still possible. The findings of this study may be useful for the management of this species not only in the River Lima
estuary but also in other locations it may invade.
Background and objective: Remifentanil boluses are used in different clinical situations and the effects on bispectral index monitoring are unclear. We analysed the effect of a remifentanil bolus on the bispectral index of the electroencephalogram (bispectral index) under total intravenous anaesthesia with propofol and remifentanil. Methods: ASA I–III patients were included in this study. All patients received a 2 μg k g−1 remifentanil bolus in a period free from stimuli. Bispectral index and haemodynamic data were collected from an A-2000XP bispectral index monitor (every second) and an AS/3 Datex monitor (every 5 s). Bispectral index data were analysed using the area under the curve. Mean arterial pressure and heart rate were averaged at each 30-s period and analysed using analysis of variance. Results: A total of 240 bispectral index values were obtained per patient. The area under the curve between 90 and 120 s after the bolus was significantly lower than the basal area under the curve (average of all areas before the bolus, P < 0.05). Mean arterial pressure and heart rate were significantly reduced from 96.4 ± 19.9 mmHg at the time of the bolus to 74.2 ± 16.6 mmHg 120 s after, and from 70 ± 16.4 bpm at the time of the bolus to 61 ± 13.6 bpm after (P < 0.001), respectively. Conclusions: There was a significant reduction in the areas under the curve between 90–120 s following the bolus. Heart rate and blood pressure also showed significant reductions. Thus, remifentanil bolus given under total intravenous anaesthesia with propofol and remifentanil decreases bispectral index, an effect independent of intubation and surgical stimuli.
Ten species of molluscs were identified in the freshwater tidal area of the River Minho estuary. Species richness per site ranged
from 1 to 9. Abundance ranged from 230 to 4130 individuals per m², with an average of 1412 individuals per m2. Corbicula
fluminea(Müller, 1774) presented the highest density, corresponding to 88.7 % of the total specimens gathered, followed by
Pisidium amnicum (Müller, 1774) with 5.8 %. Biomass ranged from 17.0 to 249.6 g AFDW m-2, with an average of 99.8 g
AFDW m-2. C. fluminea was the species dominating the total biomass (95.4 %), followed by Bithynia tentaculata (Linnaeus,
1758) with 1.6 %. A multivariate analysis revealed a community with two distinct groups : one group almost or exclusively
represented by C. fluminea, and another group with a more diverse assemblage.
Background and objective: Previous studies have shown existence of inconsistent data concerning the use of auditory-evoked potential (AEP) and electroencephalogram (EEG) changes to measure the depth of anaesthesia in regimens involving the use of opioids. The present studies characterize the effects of fentanyl on those responses in rats.
Methods: The effects of a bolus of fentanyl (6–10 μg kg−1 intravenously) alone or following naloxone (100 μg kg−1 intravenously) were examined using brain responses in rats during light anaesthesia with either propofol (20–30 mg kg−1 h−1) or isoflurane (0.8%). Electrophysiological data were recorded using silver ball electrodes. The rats' tracheas were intubated and a femoral artery cannula was inserted to monitor blood pressure. Body temperature, respiratory and pulse rate, and pedal withdrawal data were also collected. Parameters measured before and following administration of naloxone and fentanyl or of fentanyl alone were compared using repeated-measures ANOVA.
Results: Fentanyl significantly increased the latency of the major peak from the AEP during propofol and isoflurane anaesthesia (F = 13.2 and 13.5, respectively; P < 0.05) and the amplitude differential between two waveform complexes, and the second differential index (F = 28.3 and 57.2, respectively; P < 0.01). The spectral edge frequency and median frequency from the EEG tended to increase. These effects were abolished by the prior administration of naloxone.
Conclusions: These excitatory effects were inconsistent with the classical concept of brain activity depression indicating a deepening of anaesthesia.