218 research outputs found
Dietary Mg Supplementation Decreases Oxidative Stress, Inflammation, and Vascular Dysfunction in an Experimental Model of Metabolic Syndrome with Renal Failure
Background: Metabolic syndrome (MetS) and chronic kidney disease (CKD) are commonly
associated with cardiovascular disease (CVD) and in these patients Mg concentration is usually
decreased. This study evaluated whether a dietary Mg supplementation might attenuate vascular
dysfunction through the modulation of oxidative stress and inflammation in concurrent MetS and
CKD. Methods: A rat model of MetS (Zucker strain) with CKD (5/6 nephrectomy, Nx) was used.
Nephrectomized animals were fed a normal 0.1%Mg (MetS+Nx+Mg 0.1%) or a supplemented 0.6%Mg
(MetS+Nx+Mg0.6%) diet; Sham-operated rats with MetS receiving 0.1%Mg were used as controls.
Results: As compared to controls, the MetS+Nx-Mg0.1% group showed a significant increase in
oxidative stress and inflammation biomarkers (lipid peroxidation and aortic interleukin-1b and
-6 expression) and Endothelin-1 levels, a decrease in nitric oxide and a worsening in uremia and MetS
associated pathology as hypertension, and abnormal glucose and lipid profile. Moreover, proteomic
evaluation revealed changes mainly related to lipid metabolism and CVD markers. By contrast, in
the MetS+Nx+Mg0.6% group, these parameters remained largely similar to controls. Conclusion: In
concurrent MetS and CKD, dietary Mg supplementation reduced inflammation and oxidative stress
and improved vascular function.This research was funded by a Spanish government grant from the Programa Nacional
I+D+I 2008–2011 from the MINECO-Instituto de Salud Carlos III (PI20/0660 and PI21/00654) with
co-financing from European Funds (FEDER) and EUTOX and REDinREN from the ISCIII, Consejería
de Salud (grants PI-0071-2021) from the Junta de Andalucía and Grant PY20_00773 from Consejería
de Innovación, Ciencia y Empleo from the Junta de Andalucía. J.M.D.-T. hold a Sara Borrell contract
by the Spanish Ministry of Science, Innovation and Universities, Carlos III Health Institute (ISCIII),
co-funded by European Social Fund (European Social Fund-Investment in your future). Y.A. and
J.R.M.-C. are senior researchers supported by the Nicolás Monardes Programme, Consejería de
Salud-SAS (Junta de Andalucía)
La inhibición de la síntesis de óxido nítrico durante la colestasis inducida experimentalmente reduce la lesión hepatocelular al facilitar la homeostasis de nitrosotioles
Comunicaciones a congreso
Vacuum Boundary Effects
The effect of boundary conditions on the vacuum structure of quantum field
theories is analysed from a quantum information viewpoint. In particular, we
analyse the role of boundary conditions on boundary entropy and entanglement
entropy. The analysis of boundary effects on massless free field theories
points out the relevance of boundary conditions as a new rich source of
information about the vacuum structure. In all cases the entropy does not
increase along the flow from the ultraviolet to the infrared.Comment: 10 page
Estudio de la composición química y la actividad biológica de los aceites esenciales de diez plantas aromáticas colombianas
En este estudio se determinó la composición química de los aceites esenciales (AEs) de las hojas de 10 plantas aromáticas colombianas. Los AEs se aislaron empleando la técnica de hidrodestilación asistida por la radiación de microondas (MWHD) y la identificación de los componentes de los AEs se realizó mediante el análisis por cromatografía de gases – espectrometría de masas (GC-MS), utilizando dos columnas (DB-5 y DB-Wax). La identificación de los compuestos se basó en los índices de Kovàts y en la comparación de los espectros de masas con los de las bases de datos QuadLib2004, NIST 2002, Wiley 138k
Phosphorus restriction does not prevent the increase in fibroblast growth factor 23 elicited by high fat diet
This
study
was
designed
to evaluate
the
influence
of phosphorus
(P)
restriction
on
the
dele-
terious
effects
of high
fat
diets
on
mineral
metabolism.
Twenty-four
rats
were
allotted
to 3
groups
(n = 8 each)
that
were
fed
different
diets
for
7 months.
Rats
in group
1 were
fed
nor-
mal
fat-normal
P (0.6%)
diet
(NF-NP),
rats
in group
2 were
fed
high
fat-
normal
P diet
(HF-
NP)
and
rats
in group
3 were
fed
high
fat-low
P (0.2%)
diet
(HF-LP).
Blood,
urine
and
tissues
were
collected
at the
end
of the
experiments.
When
compared
with
the
control
group
(NF-
NP),
rats
fed
HF
diets
showed
increases
in body
weight,
and
in plasma
concentrations
of tri-
glycerides
and
leptin,
and
decreased
plasma
calcitriol
concentrations.
In rats
fed
HF-NP
plasma
fibroblast
growth
factor
23
(FGF23)
was
higher
(279.6
±
39.4
pg/ml
vs
160.6
±
25.0
pg/ml,
p = 0.018)
and
renal
klotho
(ratio
klotho/GAPDH)
was
lower
(0.75
±
0.06
vs
1.06
±
0.08,
p
<
0.01)
than
in rats
fed
NF-NP.
Phosphorus
restriction
did
not
normalize
plasma
FGF23
or
renal
klotho;
in fact,
rats
fed
HF-LP,
that
only
ingested
an
average
of 22.9
mg/day
of P,
had
higher
FGF23
(214.7
±
32.4
pg/ml)
concentratio
ns
than
rats
fed
NF-NP
(160.6
±
25.
0 pg/ml),
that
ingested
and
average
of 74.4
mg/day
of P over
a 7 month
period.
In conclusion,
our
results
demonstrate
that
severe
P restriction
over
a prolonged
period
of time
(7 months)
does
not
normalize
the
increase
in circulating
FGF23
induced
by
HF
diets.
These
data
indi-
cate
that
the
deleterious
effects
of high
fat
diet
on
the
FGF23/klotho
axis
are
not
eliminated
by
reduced
P intake
Double-delta potentials: one dimensional scattering. The Casimir effect and kink fluctuations
The path is explored between one-dimensional scattering through
Dirac- walls and one-dimensional quantum field theories defined on a
finite length interval with Dirichlet boundary conditions. It is found that two
's are related to the Casimir effect whereas two 's plus the
first transparent Psch-Teller well arise in the context of the
sine-Gordon kink fluctuations, both phenomena subjected to Dirichlet boundary
conditions. One or two delta wells will be also explored in order to describe
absorbent plates, even though the wells lead to non unitary Quantum Field
Theories.Comment: 15 pages. To be published in the International Journal of Theoretical
Physic
Klotho/FGF23 and Wnt Signaling as Important Players in the Comorbidities Associated with Chronic Kidney Disease
Fibroblast Growth Factor 23 (FGF23) and Klotho play an essential role in the regulation of mineral metabolism, and both are altered as a consequence of renal failure. FGF23 increases to augment phosphaturia, which prevents phosphate accumulation at the early stages of chronic kidney disease (CKD). This effect of FGF23 requires the presence of Klotho in the renal tubules. However, Klotho expression is reduced as soon as renal function is starting to fail to generate a state of FGF23 resistance. Changes in these proteins directly affect to other mineral metabolism parameters; they may affect renal function and can produce damage in other organs such as bone, heart, or vessels. Some of the mechanisms responsible for the changes in FGF23 and Klotho levels are related to modifications in the Wnt signaling. This review examines the link between FGF23/Klotho and Wnt/β-catenin in different organs: kidney, heart, and bone. Activation of the canonical Wnt signaling produces changes in FGF23 and Klotho and vice versa; therefore, this pathway emerges as a potential therapeutic target that may help to prevent CKD-associated complications
Oral Acid Load Down-Regulates Fibroblast Growth Factor 23
Increased dietary acid load has a negative impact on health, particularly when renal function is compromised. Fibroblast growth factor 23 (FGF23) is a bone-derived hormone that is elevated during renal failure. The relationship between metabolic acidosis and FGF23 remains unclear. To investigate the effect of dietary acid load on circulating levels of FGF23, rats with normal renal function and with a graded reduction in renal mass (1/2 Nx and 5/6 Nx) received oral NH4Cl for 1 month. Acid intake resulted in a consistent decrease of plasma FGF23 concentrations in all study groups when compared with their non-acidotic control: 239.3 ± 13.5 vs. 295.0 ± 15.8 pg/mL (intact), 346.4 ± 19.7 vs. 522.6 ± 29.3 pg/mL (1/2 Nx) and 988.0 ± 125.5 vs. 2549.4 ± 469.7 pg/mL (5/6 Nx). Acidosis also decreased plasma PTH in all groups, 96.5 ± 22.3 vs. 107.3 ± 19.1 pg/mL, 113.1 ± 17.3 vs. 185.8 ± 22.2 pg/mL and 504.9 ± 75.7 vs. 1255.4 ± 181.1 pg/mL. FGF23 showed a strong positive correlation with PTH (r = 0.877, p < 0.0001) and further studies demonstrated that acidosis did not influence plasma FGF23 concentrations in parathyroidectomized rats, 190.0 ± 31.6 vs. 215 ± 25.6 pg/mL. In conclusion, plasma concentrations of FGF23 are consistently decreased in rats with metabolic acidosis secondary to increased acid intake, both in animals with intact renal function and with decreased renal function. The in vivo effect of metabolic acidosis on FGF23 appears to be related to the simultaneous decrease in PTH
Boundary conditions: The path integral approach
The path integral approach to quantum mechanics requires a substantial
generalisation to describe the dynamics of systems confined to bounded domains.
Non-local boundary conditions can be introduced in Feynman's approach by means
of boundary amplitude distributions and complex phases to describe the quantum
dynamics in terms of the classical trajectories. The different prescriptions
involve only trajectories reaching the boundary and correspond to different
choices of boundary conditions of selfadjoint extensions of the Hamiltonian.
One dimensional particle dynamics is analysed in detail.Comment: 8 page
- …