8,168 research outputs found
Testosterone and aggressiveness.
Aggressiveness is an ancestral behavior common to all animal species. Its neurophysiological mechanisms
are similar in all vertebrates. Males are generally more aggressive than females. In this review,
aggressive behavior in rodents, monkeys, and man and the role of testosterone and brain
serotonin levels have been considered. Interspecifi c aggressiveness in rats has been studied considering
the mouse-killing behavior; the neonatal androgenization of females increases adult mousekilling
as does the administration of testosterone in adults. Intraspecifi c aggressiveness was studied
by putting two or more male rats (or mice) in the same cage; the condition of subjection or dominance
is infl uenced by testosterone.
In monkeys, testosterone is related to aggressiveness and dominance and, during the mating season,
increases in testosterone levels and aggressive attitude are observed. In men, higher testosterone
levels were obtained in perpetrators of violent crimes, in men from the army with antisocial
behaviors, in subjects with impulsive behaviors, alcoholics and suicidals, in athletes using steroids,
and during competitions. Aggressive and dominant behavior are distinguished. Testosterone infl
uences both of these, even if man is usually inclined to affi rm his power without causing physical
damage. Testosterone receptors are mainly in some hypothalamic neurons, where it is aromatized
into estrogens, which determine the increase in aggressiveness. A relation between testosterone
levels and diencephalic serotonin has been shown: in fact, the lack of serotonin increases aggressive
behaviors both in animals and man. Testosterone also increases ADH levels in the medial amygdala,
lateral hypothalamus, and preoptical medial area, involved in aggressive behaviors
Searching for New Long Lived Particles in Heavy Ion Collisions at the LHC
We show that heavy ion collisions at the LHC provide a promising environment
to search for new long lived particles in well-motivated New Physics scenarios.
One advantage lies in the possibility to operate the main detectors with looser
triggers, which can increase the number of observable events by orders of
magnitude if the long lived particles are produced with low transverse
momentum. In addition, the absence of pileup in heavy ion collisions can avoid
systematic nuisances that will be present in future proton runs, such as the
problem of vertex mis-identification. Finally, there are new production
mechanisms that are absent or inefficient in proton collisions. We show that
the looser triggers alone can make searches in heavy ion data competitive with
proton data for the specific example of heavy neutrinos in the Neutrino Minimal
Standard Model, produced in the decay of B mesons. Our results suggest that
collisions of ions lighter than lead, which are currently under discussion in
the heavy ion community, are well-motivated from the viewpoint of searches for
New Physics.Comment: Version accepted by Physical Review Letters for publication as a
Letter. 6 pages, 3 figure
Therapeutic Effectiveness of Nutrition Therapy in Pediatric Patients with Chronic Liver Diseases Awaiting Liver Transplantation
Abstract
It is important to prevent protein/calorie malnutrition in children with end stage liver diseases prior to
transplantation. This study involved 34 patients between the ages of 10 and 156 months (mean value 25.69
months 32.2) (13 females and 21 males) on the liver transplant waiting list. Data collected as of three months
before transplant and up to ten months after the procedure concerned gender, age, weight, height, Pediatric End
Stage Liver Disease Score, baseline pathology, type of nutrition, type of transplant, immunosuppression, pulse
steroid therapy, length of stay, and post transplant complications. Linear regression analysis showed that the
length of hospital stay was 24.5 days more for females than for males, but also that intensive nutrition therapy
shortens this stay for both female patients (P = 0.085) and younger patients (P = 0.023). The study population
was divided into two groups according to the different nutritional therapies adopted. The Student’s t-test and
Mann-Whitney test evidenced that the group receiving intensive nutrition therapy grew taller compared with the
group following an oral diet (mean -1.37 and Prob = 0.043); that females grew taller compared to males (mean
-1.65 +/- 0.56); and that there was an increase in height among the children in the group receiving intensive
nutrition therapy despite the presence (-1.37 +/- 0.56) or absence (-14.8 +/- 5.44 and Prob = 0.035) of
complications, and despite the administration (-1.03 +/- 0.33) or non administration (-1.48 +/- 0.55 and Prob =
0.019) of steroids. Intensive nutrition therapy enhances the velocity of growth in height and shortens the length
of hospital stay, thus optimizing the final prognosis of the baseline pathology
Follistatin as potential therapeutic target in prostate cancer
Follistatin is a single-chain glycosylated protein
whose primary function consists in binding and neutralizing
some members of the transforming growth factor-β superfamily
such as activin and bone morphogenic proteins.
Emerging evidence indicates that this molecule may also
play a role in the malignant progression of several human
tumors including prostate cancer. In particular, recent findings
suggest that, in this tumor, follistatin may also contribute
to the formation of bone metastasis through multiple
mechanisms, some of which are not related to its specific
activin or bone morphogenic proteins’ inhibitory activity.
This review provides insight into the most recent advances
in understanding the role of follistatin in the prostate cancer
progression and discusses the clinical and therapeutic implications
related to these findings
PLASMA MEMBRANE REDOX SYSTEM IN THE ERYTHROCYTES OF ROWERS: PILOT STUDY
Background: The oxidative stress results from a change in the physiological balance
between oxidant and antioxidant species. The purpose of this study is twofold: first, to investigate
the effects of long-term training in sports with high energy requirements on the redox balance
which exists between the plasma vs. the erythrocytes; second, to study the activity of the PMRS
(Plasma Membrane Redox System), which is a compensatory mechanism of cellular redox
homeostasis, in the rowers’ erythrocytes in order to determine the rowers’ counteraction to
oxidative stress.
Methods: Venous blood samples was collected from rowers and control group; then FRAP
(Ferric Reducing Activity Power) method has been used to determine the antioxidant capabilities
both in the plasma and in the erythrocytes of 22 rowers vs. 26 sedentary subjects. For the same
groups of subjects, the PMRS in erythrocytes has been also evaluated.
Results: The plasmatic antioxidant activity was 21% lower in the group of rowers compared
to the sedentary group (p = 0,02). In contrast, no significant differences were found in the reducing
activity of the erythrocytes; however the erythrocytes of the rowers have shown values of the
PMRS 35% higher than the untrained group (p < 0.0001).
Conclusions: Rowing induces a significant oxidative stress in the plasma corresponding to
the high intensity training, while this effect lacks in erythrocytes. At the same time an increased
quantity of the PMRS has been observed in the erythrocytes. In conclusion, in well trained athletes
this not lead to established an oxidative stress condition because long-term training adaptatively
improves the efficiency of the antioxidant syste
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