Difference between heartwood and sapwood
Forest Products Laboratory (U.S.)
1919
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198 records were found.
Manipulation of corticosteroid milieu during perinatal period has received much attention due to
its implications in pathology later in life. The experience of stressful/traumatic events in early
childhood, which triggers the activation of the HPA axis and the permanent increase in
corticosteroids levels during critical periods of development, has shown to be associated with
cardiovascular, metabolic, immune and psychiatric conditions. Interesting links have indeed,
been established between psychopathology and immune dysfunction, although the exact
mechanisms by which neuroendocrine and immune system interact, and influence each other,
still need further investigation. For that reason, in this collection of studies we investigated the
impact in nervous, endocrine and immune systems, of an early stressful event (maternal
separation -MS)...
In the field of clinical obstetrics, glucocorticoids (GCs) have gained an
important role in promoting fetal lung maturation, and are used in about 10% of
risk pregnancies. The fetus is highly sensitive to perturbations of its chemical
environment along critical developmental windows and, thus, it is not surprising
that stress exposure or GC treatment during pregnancy cause notable changes in
the physiology and behaviour of the offspring in adulthood. In fact, lifelong
implications of sustained deleterious perinatal experiences, such as elevated GCs,
include anxiety, mood and cognitive disorders as well as the development of
addictive‐like behaviors. It seems that during these crucial periods, several brain
regions might be programmed by prolonged stressful insults, such as exposure
to high doses of GCs. However, less is known about the...
Post-natal neurogenesis is one of the most interesting brain events disclosed in the last century,
with its modulation promising a new approach to the treatment of some central nervous system
(CNS) pathologies. Despite the expectations, its clinical application is not yet a reality, mainly
because the information concerning its function and regulatory mechanisms is still insufficient.
In order to better understand the mechanisms that regulate adult neurogenesis, we decided to
assess the topographic distribution of hippocampal neurogenesis and apoptosis in basal conditions
(Chapter 2.1). We showed that neither neurogenesis nor apoptosis occur homogeneously within the
dentate gyrus as each of these events display different gradients. Therefore, the existence of
specific gradients of cell birth/death in the adult hippocampal formation is ...
Stress is a powerful modulator of emotional behavior and is implicated in the etiology of mood
disorders like anxiety, depression and phobias. Mood disorders are particularly common and
affect a large percentage of the world population with relevant implications to individual’s health
and to the society. Fear and anxiety represent specific aspects of emotional behavior that show
behavioral resemblances but are triggered by events that activate distinct neuronal pathways:
while the amygdala plays a key role in fear-conditioned to cue stimuli, the bed nucleus of the stria
terminalis (BNST) is implicated in anxiety behavior and responses to contextual stimuli. In
addition, the BNST is directly involved in the regulation of the hypothalamo-pituitary-adrenal
(HPA) axis being an important relay station of limbic inputs. In the present work, ...
Up to 7-10% of the pregnant women receive at least one dose of
synthetic glucocorticoids (GC) in order to promote fetal lung maturation
and, despite animal and human data suggesting growth restriction and
other deleterious effects on the developing brain and other organs, the
use of repeated doses still occurs in clinical practice. Moreover, it is
established that early life adverse events can shape physical and mental
health in adulthood. In fact, there is accumulating evidence that
exposure to stress or elevated levels of GC during crucial stages of
development contributes for the appearance of neurospyschiatric
conditions, such as anxiety and depression.
In the present work, we assessed the impact of exposure to
dexamethasone (DEX), a synthetic GC widely used in clinics, during
gestational days 18-19 on the adult progeny. Following ...
Depression is a highly prevalent mood disorder that inflicts a heavy burden in depressed patients and a
significant social and economic impact worldwide. Nevertheless, the precise physiopathological
mechanisms involved in its aetiology and in the therapeutic actions of antidepressant drugs are still largely
unknown. Previous studies have implicated different neuroplastic phenomena in the neurobiological basis
of depression. In particular, the role of adult neurogenesis in the hippocampus and dendritic and synaptic
plasticity in different brain regions in the behavioural actions of antidepressant drugs has been the focus of
recent attention in this field of research. In the present work, we addressed the behavioural interactions of
mood, anxiety and cognition in an animal model of depression, taking into account the neuroplastic events
...
Multiple areas along the neuroaxis mediate pain modulation and perception. Dysfunction at
any of these stations can have devastating consequences that result in pain chronification and
in the surfacing of emotional and cognitive disturbances. In the past decade, it was
demonstrated that these comorbidities frequently associated with chronic pain also manifest in
the animal model, paving the way for further research on the underling pathophysiology.
However, conflicting observations have been published probably as a result of experimental
heterogeneity. This prompted us to further characterize emotional and cognitive behaviour
alterations in a rodent model of chronic neuropathic pain – the spared nerve injury (SNI).
In the first set of experiments, the effect of chronic neuropathic pain was studied in the context
of ageing. We observed ...
Pain is an essential tool for survival, but equally important is the ability to overcome pain in life
threatening events, allowing us to react. Stress-induced analgesia exemplifies this concept as a
strong acute stressor activates the hypothalamic-pituitary-adrenal glands (HPA) axis and leads to
the release of adrenaline, dampening pain processing and resulting in transient analgesia. This
initial response is followed by the release of corticosteroids in order to re-establish physiological
homeostasis. On the other hand, the effects of chronic stress upon pain perception are not
consensual as both inhibition (analgesia) and facilitation (hyperalgesia) of nociception has been
reported in different contexts. Additionally, several studies showed that patients suffering from
chronic pain display altered HPA axis function, suggesting an int...
O presente estudo teve como principal objectivo descrever e compreender o
crescimento físico, funcionamento neuro-endócrino e o desenvolvimento mental de
crianças colocadas em instituições Portuguesas, ao longo da sua permanência na
instituição e desde o momento de admissão. Pretendia-se também compreender a
contribuição de factores individuais da criança e ambientais para os resultados nos
domínios do desenvolvimento acima mencionados. Trinta e uma crianças, com idades
até aos 30 meses, foram avaliadas no momento de admissão na instituição e em mais
três momentos subsequentes. As cuidadoras institucionais também participaram no
estudo. O crescimento físico (Direcção-Geral de Saúde, 2005), desenvolvimento mental
(Bayley, 2006), e produção diurnal de cortisol (funcionamento neuro-endócrino) foram
avaliados em quatro momentos de avaliaçã...
This work, initially, had as cornerstone, the energy optimization of a tanning industry, more particularly the Dias Ruivo. The aim was to assess all energy expenditures submitted by the company in order to ascertain whether there was possibility of reducing electricity bills and associated costs while maintaining quality of final products. Although it was intended to investigate the feasibility of reusing waste allowing some decrease the amount of energy required for heating some water currents. Finally, after the data collected were suggested improvement measures that would allow the company to use its resources optimally, thus presenting no unnecessary spending.
Starting with the analysis of the electricity bill, it was found that in the years 2010 and 2011, the company presented a power consumption of 123 and 133 tep/year, respectiv...
