Spontaneously hypertensive rats (SHRs) ingest more NaCl than normotensive strains. Here we investigated NaCl intake and taste reactivity in adult male SHRs and normotensive Holtzman rats treated or ...not with AT1 receptor antagonist centrally in euhydrated condition and after fluid depletion. Taste reactivity was measured by the number of orofacial expressions to intra-oral infusions of 0.3 M NaCl. In euhydrated condition, intra-oral infusions of 0.3 M NaCl produced greater number of hedonic responses in SHRs than in normotensive rats, without differences in the number of aversive responses. Compared to euhydrated condition, the treatment with the diuretic furosemide + low dose of captopril (angiotensin converting enzyme blocker) increased the number of hedonic and reduced the number of aversive responses to intra-oral NaCl in normotensive rats, without changing the number of hedonic or aversive responses in SHRs. Losartan (AT1 receptor antagonist, 100 ng/1 μl) injected intracerebroventricularly in SHRs abolished 0.3 M NaCl intake induced by water deprivation + partial rehydration, whereas only transiently (first 30 min of the 60 min test) reduced hedonic responses, without changes in aversive responses to intra-oral NaCl. Losartan intracerebroventricularly also only transiently (first 30 min) reduced the number of hedonic responses to intra-oral NaCl in euhydrated SHRs. The results suggest that NaCl palatability is increased and independent from body fluid balance in SHRs. The results also suggest that central AT1 receptors are part of the mechanisms activated to increase NaCl intake and palatability in SHRs. A partial dissociation between NaCl intake and palatability in SHRs is also suggested.
•Spontaneously hypertensive rats show increased palatability to intraoral 0.3 M NaCl.•Changes in fluid balance do not modify NaCl palatability in spontaneously hypertensive rats.•Sodium palatability in spontaneously hypertensive rats depends on central AT1 receptor activation.
Recent studies have shown that the behaviour and development of coral reef fish larvae is hampered by projected future CO
2
levels. However, it is uncertain to what extent this effect also occurs in ...temperate species. The effects that elevated
p
CO
2
(~2000 µatm) levels, which are expected to occur in coastal upwelling regions in the future, have on shoaling behaviour and lateralization (turning preference) of fish, were tested in temperate sand smelt
Atherina presbyter
larvae. The hypothesis that behavioural changes are caused by interference of high CO
2
with GABA-A receptor function was tested by treating larvae with a receptor antagonist (gabazine). Routine swimming speed did not differ between control and high
p
CO
2
, but exposure to high
p
CO
2
for 7 days affected group cohesion, which presented a more random distribution when compared to control fish. However, this random distribution was reversed after 21 days of exposure to high CO
2
conditions. Lateralization at the individual level decreased in fish exposed to high
p
CO
2
for 7 and 21 days, but gabazine reversed this decline. This adds to the growing body of evidence that the effects of a more acidified environment on fish larvae behaviour are likely due to altered function of GABA-A receptors. Overall, our results suggest that future
p
CO
2
levels likely to occur in temperate coastal ecosystems could have an adverse effect on temperate larval fish behaviour.
Ana Filipa Moleiro,1,2 Gonçalo Godinho,3 Carolina Madeira,4 Ana Faria Pereira,1 Elisete Brandão,1 Fernando Falcão-Reis,1,2 João Nuno Beato,1,2 Susana Penas1,2 1Department of Ophthalmology, Centro ...Hospitalar e Universitário de São João, Porto, Portugal; 2Department of Surgery and Physiology, Faculdade de Medicina da Universidade do Porto, Porto, Portugal; 3Department of Ophthalmology, Centro Hospitalar de Leiria, Leiria, Portugal; 4Department of Ophthalmology, Centro Hospitalar Gaia-Espinho, Gaia, Portugal Correspondence: Ana Filipa Moleiro, Department of Ophthalmology, Centro Hospitalar e Universitário de São João, Alameda Hernani Monteiro, Porto, 4200-426, Portugal, Tel +351 915689259, Email email protected View the original paper by Dr Moleiro and colleagues This is in response to the Letter to the Editor
Oral tolerance is defined as a state of systemic hyporesponsiveness to an antigen that has been previously administered by the oral route. Many factors affect oral tolerance induction; some of them ...related to antigen, and some related to the animal. The age of the animal is one of the most important factors that affect oral tolerance as ageing brings many alterations in immune responses. Herein, we demonstrated that both the oral tolerance and pattern of immune reactivity triggered in early life were kept up to 15 months regarding the magnitude of antibody production, cell proliferation and cytokine profile when compared to immune responses induced in old mice. Therefore, our results corroborate with a promising proposal for prevaccination during childhood and young age, and a booster in older age, to make sure that the primary immunization in early life is not lost in aged individuals.
Two experiments were designed to evaluate the effect of mineral-amino acid complexes (AACM) as a partial replacement of inorganic mineral (IM) in layer-type chicks' diets. Both studies had the same ...dietary treatments, where in experiment 1 (Exp. 1) was conducted under thermoneutral conditions from 0 to 35 D and chicks in experiment 2 (Exp. 2) were exposed to cold stress conditions at nighttime during the first 15 D and to thermoneutral condition from 16 to 35 D. For each trial, 1,200 one-day-old Lohmann Brown chicks were used, with 20 cage replicates with 30 chicks per cage. Treatments consisted of the control diet (IM; with 70, 70, and 8 mg/kg of zinc Zn, manganese Mn, and copper Cu, respectively) and the treatment diet (AACM, with 40, 40, and 2.75 mg/kg of Zn, Mn, and Cu, respectively, from IM sources, along with 30, 30, and 5.25 mg/kg of Zn, Mn, and Cu, respectively). Data were submitted to analysis of variance, and means were compared using the t-test (P < 0.05). In Exp. 1, there were no significant differences between treatments on chick performance. However, AACM-fed chicks had higher thymus (P = 0.03) and cecum weight (P < 0.01), superior micromineral deposition in the tibias (P < 0.01), and reduced phosphorus excretion (P = 0.03). In Exp. 2, chicks fed with AACM had higher body weight gain (P = 0.04), better average daily feed intake (P = 0.03), lower phosphorus excretion (P = 0.02), and higher liver and pancreas weight (P < 0.01) in the last week of the study. In conclusion, chicks fed with AACM under thermoneutral conditions had higher bone mineralization and reduced excretion of phosphorus, and in adverse conditions, AACM improves performance and liver and pancreas weight, also reducing phosphorus excretion.
Fishes are currently facing novel types of anthropogenic stressors that have never experienced in their evolutionary history, such as ocean acidification. Under these stressful conditions, ...energetically costly processes, such as reproduction, may be sacrificed for increased chances of survival. This trade-off does not only affect the organism itself but may result in reduced offspring fitness. In the present study, the effects of exposure to high pCO2 levels were tested on the reproductive performance of a temperate species, the two-spotted goby, Gobiusculus flavescens. Breeding pairs were kept under control (∼600 μatm, pH∼ 8.05) and high pCO2 levels (∼2300 μatm, pH∼ 7.60) conditions for a 4-month period. Additionally, oxidative stress and energy metabolism-related biomarkers were measured. Results suggest that reproductive activity is stimulated under high pCO2 levels. Parental pairs in the simulated ocean acidification conditions exhibited increased reproductive output, with 50% more clutches and 44% more eggs per clutch than pairs under control conditions. However, there was an apparent trade-off between offspring number and size, as larvae of parental pairs under high pCO2 levels hatched significantly smaller, suggesting differences in parental provisioning, which could be related to the fact that these females produce more eggs. Moreover, results support the hypothesis of different energy allocation strategies used by females under high pCO2 conditions. These changes might, ultimately, affect individual fitness and population replenishment.
Display omitted
•Reproductive activity in two-spotted goby is stimulated under high pCO2 levels.•Females under high pCO2 levels produce more eggs.•Larvae of parental pairs under high pCO2 levels hatch smaller.•Different energy allocation strategies are used by females under .•High pCO2 levels.
Dietary non-heme iron contains ferrous Fe(II) and ferric Fe(III) iron fractions and the latter should hydrolyze, forming Fe(III) oxo-hydroxide particles, on passing from the acidic stomach to less ...acidic duodenum. Using conditions to mimic the in vivo hydrolytic environment we confirmed the formation of nanodisperse fine ferrihydrite-like particles. Synthetic analogues of these (~ 10 nm hydrodynamic diameter) were readily adherent to the cell membrane of differentiated Caco-2 cells and internalization was visualized using transmission electron microscopy. Moreover, Caco-2 exposure to these nanoparticles led to ferritin formation (i.e., iron utilization) by the cells, which, unlike for soluble forms of iron, was reduced (p=0.02) by inhibition of clathrin-mediated endocytosis. Simulated lysosomal digestion indicated that the nanoparticles are readily dissolved under mildly acidic conditions with the lysosomal ligand, citrate. This was confirmed in cell culture as monensin inhibited Caco-2 utilization of iron from this source in a dose dependent fashion (p<0.05) whilet soluble iron was again unaffected. Our findings reveal the possibility of an endocytic pathway for acquisition of dietary Fe(III) by the small intestinal epithelium, which would complement the established DMT-1 pathway for soluble Fe(II).
Packaging system and probiotic dairy foods da Cruz, Adriano G.; Faria, José de A.F.; Van Dender, Ariene G.F.
Food research international,
10/2007, Letnik:
40, Številka:
8
Journal Article
Recenzirano
The consumption of foods containing probiotic cultures has greatly increased over the past years as a result of their benefits to human health. Along with other factors, the choice of the packaging ...material plays an important role in maintaining viable counts of these microorganisms at sufficiently high levels to assure their therapeutic activity throughout shelf-life. The aim of this article is to provide an overview of the main issues related to the importance of the packaging system and/or materials on the stability of probiotic dairy foods.
Purpose: This work aimed to longitudinally assess the peripapillary (PPCT) and subfoveal (SFCT) choroidal thickness (CT), in patients diagnosed with central (CRVO) or branch retinal vein occlusions ...(BRVO), correlating SFCT with central macular thickness (CMT) and PPCT with peripapillary retinal nerve fiber layer thickness (pRNFL). Patients and Methods: This was a retrospective longitudinal study of 71 eyes from 71 patients with treatment-naive retinal vein occlusion (24 CRVO and 40 BRVO). Spectral-domain optical coherence tomography (SD-OCT, Spectralis HRA-OCT, Heidelberg) was used to measure PPCT, SFCT, pRNFL and CMT of the affected and fellow eyes at baseline (acute phase) and at 3 and 9 months post anti-VEGF treatment. IBM SPSS Statistics version 27.0 (IBM Corp., Armonk, NY, USA) was used for statistical analysis. A p-value <0.05 was considered statistically significant. Results: Affected eyes presented a thicker baseline PPCT and SFCT compared to their fellow eyes both in CRVO and BRVO (p < 0.05). Both groups presented a significant decrease of PPCT in the affected eyes at 3 months compared to baseline (p < 0.05). At 9 months, compared to 3 months, PPCT remained stable (p > 0.05). Similarly, affected eyes' SFCT significantly decreased at 3 months (p < 0.05) in both groups. At 9 months, compared to 3 months, SFCT decreased in the CRVO patients (p = 0.047) but remained stable in the BRVO patients (p = 0.850). No correlations between SFCT and CMT were seen at any timepoint in both groups (p > 0.05). PPCT correlates with pRNFL in CRVO at 3 months, although no other correlations were found during the follow-up. In BRVO, PPCT did not show any significant correlation with pRNFL. Conclusion: Both in CRVO and BRVO eyes, PPCT and SFCT at diagnosis are significantly thicker compared to the fellow eye, suggesting a possible increase in CT immediately after the occlusion, which is followed by a decrease at an early follow-up stage. Keywords: biomarkers, vascular retinal diseases, retinal vein occlusions, choroidal thickness, optical coherence tomography
Context.
The ESPRESSO spectrograph is a new powerful tool developed to detect and characterize extrasolar planets. Its design allows an unprecedented radial velocity precision (down to a few tens of ...cm s
−1
) and long-term thermomechanical stability.
Aims.
We present the first stand-alone detection of an extrasolar planet by blind radial velocity search using ESPRESSO; our aim is to show the power of the instrument in characterizing planetary signals at different periodicities in long observing time spans.
Methods.
We used 41 ESPRESSO measurements of HD 22496 obtained within a time span of 895 days with a median photon noise of 18 cm s
−1
. A radial velocity analysis was performed to test the presence of planets in the system and to account for the stellar activity of this K5-K7 main-sequence star. For benchmarking and comparison, we attempted the detection with 43 archive HARPS measurements and in this work we compare the results yielded by the two datasets. We also used four TESS sectors to search for transits.
Results.
We find radial velocity variations compatible with a close-in planet with an orbital period of
P
= 5.09071 ± 0.00026 days when simultaneously accounting for the effects of stellar activity on longer timescales (
P
rot
= 34.99
−0.53
+0.58
days). We characterize the physical and orbital properties of the planet and find a minimum mass of 5.57
−0.68
+0.73
M
⊕
, right in the dichotomic regime between rocky and gaseous planets. Although not transiting according to TESS data, if aligned with the stellar spin axis, the absolute mass of the planet must be below 16
M
⊕
. We find no significant evidence for additional signals in the data with semi-amplitudes above 56 cm s
−1
at 95% confidence.
Conclusions.
With a modest set of radial velocity measurements, ESPRESSO is capable of detecting and characterizing low-mass planets and constraining the presence of planets in the habitable zone of K dwarfs down to the rocky-mass regime.
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