10,982 research outputs found
Thyroid hormone receptors and ligand, tissue distribution and sexual behavior
The thyroid hormones (THs) triiodothyronine (T3) and tetraiodothyronine,
or thyroxine (T4), not only dramatically impact on
development and differentiation, but also on the sexual and
reproductive function. There is large body of literature, in fact, on
the effects of THs on the reproductive function in both humans
(Poppe and Velkeniers, 2004; Wajner et al., 2009) and animals
(Hapon et al., 2010; Nelson et al., 2011).
For a long time the gonads were thought to be unresponsive to
THs, but TH receptors (TR) were discovered in rat (Jannini et al.,
1990; Palmero et al., 1988) and then in human testis (Jannini
et al., 2000). In women, the association of menstrual disturbance
with thyroid disease was described as early as 1840 by von Basedow,
but the discovery of TRs in the ovary was carried out at the
end of last century (Wakim et al., 1994b). Therefore, the link between
thyroid and reproductive function was well established.
Since then, research has shown that thyroid dysfunction is associated
with an adverse effect on fertility, both in men (Wagner et al.,
2009) and women (Dittrich et al., 2011). There is also evidence that
THs can affect the sex steroid hormone axis (Bagamasbad and
Denver, 2011), consequently sexual hormones and the pituitary
gland can mediate the action of THs on the reproductive
physiology.
While the effects of THs on fertility have been widely studied,
little is known about their influence on sexual function. In the last
few years, an increasing number of evidences have shown the influence
of THs on male sexual function, particularly on ejaculation
control as well on desire and erectile function (Carani et al., 2005;
Corona et al., 2012b; Di Sante et al., 2016). The female sexual
function and the relationship with thyroid function is still less
studied. Furthermore, studies conducted on animals have shown
the presence of TRs in the male (Carosa et al., 2010) and female
genitalia (Rodriguez-Castelan et al., 2017). Moreover, knockout
mice for TRs showed alterations in sexual behavior (Dellovade et al.,
2000).
The purpose of this review is to summarize and discuss the
available data on the influence of THs on male and female sexual
function to understand the molecular mechanisms of the influence
of the thyroid gland on sexual behavior and function
Scaling dependence on time and distance in nonlinear fractional diffusion equations and possible applications to the water transport in soils
Recently, fractional derivatives have been employed to analyze various
systems in engineering, physics, finance and hidrology. For instance, they have
been used to investigate anomalous diffusion processes which are present in
different physical systems like: amorphous semicondutors, polymers, composite
heterogeneous films and porous media. They have also been used to calculate the
heat load intensity change in blast furnace walls, to solve problems of control
theory \ and dynamic problems of linear and nonlinear hereditary mechanics of
solids. In this work, we investigate the scaling properties related to the
nonlinear fractional diffusion equations and indicate the possibilities to the
applications of these equations to simulate the water transport in unsaturated
soils. Usually, the water transport in soils with anomalous diffusion, the
dependence of concentration on time and distance may be expressed in term of a
single variable given by In particular, for the
systems obey Fick's law and Richards' equation for water transport. We show
that a generalization of Richards' equation via fractional approach can
incorporate the above property.Comment: 9 page
Are the therapeutic strategies in anorexia of ageing effective on nutritional status? A systematic review with meta-analysis
BACKGROUND:
Anorexia of ageing (AA) may be considered as a risk factor for frailty and has an important impact on quality of life, morbidity and mortality.
METHODS:
A systematic review and a meta-analysis were performed to summarise the results from several trials on the effectiveness of treatments in AA, as associated with depression, sensory impairment of taste and smell, decreased appetite or early satiety, and disability. Eligible studies were required to report baseline and follow-up values, the mean change (∆-change) from baseline, and/or the mean difference among intervention groups versus control group, concerning food intake (kcal/daily) and/or nutritional outcomes, such as body weight, body mass index, albumin and Mini Nutritional Assessment.
RESULTS:
The systematic review included 20 papers based on different therapeutic approaches concerning food intake and/or nutritional outcomes. The results of the meta-analysis indicate that the interventions for AA have an important impact on body weight [+1.59 kg; 95% confidence interval (CI) = 1.48-+1.71 kg; P < 0.001) and on energy intake (+56.09 kcal; 95% CI = -54.05 to +166.25 kcal; P = 0.32). Regarding secondary outcomes, it was not possible to meta-analyse the limited amount of data availab le.
CONCLUSIONS:
The different variants of AA need to be defined because diverse therapeutic approaches are available. A more precise definition of the functional impairments associated with AA may allow a more correct decision about the most appropriate therapy to be prescribed. Moreover, this may allow for a more effective performance of the different therapeutic approaches once they are better targeted to the different scenarios of AA
Excitation of the GDR and the Compressional Isoscalar Dipole State by alpha scattering
The excitation of the isovector giant dipole resonance (GDR) by alpha
scattering is investigated as a method of probing the neutron excess in exotic
nuclei. DWBA calculations are presented for 28O and 70Ca and the interplay of
Coulomb and nuclear excitation is discussed. Since the magnitude of the Coulomb
excitation amplitude is strongly influenced by the Q-value, the neutron excess
plays an important role, as it tends to lower the energy of the GDR. The
excitation of the compressional isoscalar dipole state in 70Ca by alpha
scattering is also investigated. It is shown that the population of this latter
state may be an even more sensitive probe of the neutron skin than the
isovector GDR.Comment: 7 pages, 5 figures, Latex2
The andrologist from medicine of reproduction to sexual medicine: the Italian experience
The main andrological areas of interest, male reproductive and - more recently sexual dysfunctions are most appropriately viewed as symptoms of the couple with medical, psychological and behavioural components that cannot be treated in a mechanical, purely medicinal manner (sexual medicine). The patient and his sexual partner must be active participants in a full continuum of care (medical sexology), the new challenge for the renewed and enriched field of andrology. In this field, the cooperation between basic researchers (such as geneticists, neurophysiologists, pharmacologists, ethologists) and a wide group of clinicians (such as endocrinologists, psychologists and psycho-sexologlsts, psychiatrists, urologists and gynaecologists) is of paramount importance for the andrologist at the dawn of the new field of medical sexology, which will be full of scientific gratification in the years to come
On the dynamics of bubbles in boiling water
We investigate the dynamics of many interacting bubbles in boiling water by
using a laser scattering experiment. Specifically, we analyze the temporal
variations of a laser intensity signal which passed through a sample of boiling
water. Our empirical results indicate that the return interval distribution of
the laser signal does not follow an exponential distribution; contrariwise, a
heavy-tailed distribution has been found. Additionally, we compare the
experimental results with those obtained from a minimalist phenomenological
model, finding a good agreement.Comment: Accepted for publication in Chaos, Solitons & Fractal
- …