Publications by authors named "Pedro A Pereira"

Ptosis and proximal weakness may develop in multiple diseases including oculopharyngeal muscular dystrophy (OPMD) and myasthenia gravis (MG). These two entities can be challenging to differentiate since they may have important clinical and neurophysiological overlap. Systemic lupus erythematosus (SLE), a common autoimmune disease, has been described in association with MG.

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We compared the effects of two different high-caloric diets administered to 4-week-old rats for 12 weeks: a diet rich in sugar (30% sucrose) and a cafeteria diet rich in sugar and high-fat foods. We focused on the hippocampus, particularly on the gamma-aminobutyric acid (GABA)ergic system, including the Ca-binding proteins parvalbumin (PV), calretinin (CR), calbindin (CB), and the neuropeptides somatostatin (SST) and neuropeptide Y (NPY). We also analyzed the density of cholinergic varicosities, brain-derived neurotrophic factor (), reelin (), and cyclin-dependent kinase-5 () mRNA levels, and glial fibrillary acidic protein (GFAP) expression.

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Several studies reported anatomical variations in the sinoatrial node artery (SANa). Here, we report a rare variation in the origin of the SANa on a human adult male cadaver. During dissection, we identified the SANa originating from a large atrial branch of the right coronary artery (RCA).

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Purpose: To examine the lateral rectus muscle pulley and its bony insertion concerning the orbital rim and periorbita.

Design: Prospective. An observational anatomic study.

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Article Synopsis
  • * Cholinergic neurons, which heavily innervate the BLA and rely on nerve growth factor (NGF) for their survival and function, were examined to see if aging impacts their density and if NGF treatment could reverse any changes.
  • * The study found that while the number of NPY-positive neurons decreases with age, this decline can be reversed with NGF infusion; however, the overall density of cholinergic varicosities remains stable across age groups
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Background: The heel is a complex anatomical region and is very often the source of pain complaints. The medial heel contains a number of structures, capable of compressing the main nerves of the region and knowing its anatomical topography is mandatory. The purpose of this work is to evaluate if tibial nerve (TN) and its main branches relate to the main anatomical landmarks of the ankle's medial side and if so, do they have a regular path after emerging from TN.

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Because most of the recognized causes of superior gluteal nerve (SGN) injury are iatrogenic, detailed knowledge of the anatomy of the SGN is crucial to prevent its injury associated with surgical procedures. This study aims to describe the precise location of SGN or its branches at the greater sciatic foramen, measure the distances of these neural structures to palpable bony landmarks, and evaluate the possible correlation between these parameters and pelvis size. Twenty human cadaveric hemipelvises were studied.

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High-caloric diets induce several deleterious alterations in the human body, including the brain. However, information on the effects of these diets on the elderly brain is scarce. Therefore, we studied the effects of 2 months of treatment with high-fat (HF) and high-fat-high-sugar (HFHS) diets on aged male Wistar rats at 18 months.

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Background: Minimally invasive lateral lumbar interbody fusion is a technique that has become increasingly popular for the treatment of degenerative lumbar spine disease; however, the pertinent surgical vascular anatomy has not been examined in detail. The goal of this study is to examine the anatomy of the lower lumbar and median sacral arteries, which are important determinants of these surgical outcomes.

Methods: This is an observational, experimental study based on cadaveric models, including 20 embalmed adult human cadavers.

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Investigations using preclinical models of preterm birth have much contributed, together with human neuropathological studies, for advances in our understanding of preterm brain injury. Here, we evaluated whether the neurodevelopmental and behavioral consequences of preterm birth induced by a non-inflammatory model of preterm birth using mifepristone would differ from those after inflammatory prenatal transient hypoxia-ischemia (TSHI) model. Pregnant Wistar rats were either injected with mifepristone, and pups were delivered on embryonic day 21 (ED21 group), or laparotomized on the 18th day of gestation for 60 min of uterine arteries occlusion.

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Dopamine neurons in the ventral tegmental area (VTA) play a main role in processing both rewarding and aversive stimuli, and their response to salient stimuli is significantly shaped by afferents originating in the brainstem cholinergic nuclei. Aging is associated with a decline in dopaminergic activity and reduced response to positive reinforcement. We have used stereological techniques to examine, in adult and aged rats, the dopaminergic neurons and the cholinergic innervation of the VTA, and the cholinergic populations of the pedunculopontine tegmental (PPT) and laterodorsal tegmental (LDT) nuclei, which are the only source of cholinergic inputs to the VTA.

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Purpose: The purpose of this study was to analyse the anatomic course of the radial nerve (RN) in the arm, in order to minimize the potential risk of surgical injury.

Methods: The study was performed in 19 embalmed upper extremities of 11 adult human cadavers. We measured: distance from deltoid insertion (DI) into the humerus to lateral epicondyle (LE); distance from RN piercing point into the lateral intermuscular septum (LIS) to three other points-DI, LE and RN division into superficial and deep terminal branches; distance between the LE and the RN division.

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Purpose: The authors intend, by presenting a case study, emphasize the neuromodulation process of orofacial pain induced by the stimulation of the sensory and motor stimulation of the trigeminal nerve, which can play an important role on pain modulation.

Materials And Methods: A 25 year-old woman presenting orofacial pain was referred to the stomatology service at the Centro Hospitalar do Porto. After collecting the patient's anamnesis, the thermographic camera FLIR i7 was used to record the thermal status of the orofacial structures, before the adhesive dentistry sensory stimulus protocol, after 45 minutes, and after one week.

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The brain cholinergic system comprises two main recognized subdivisions, the basal forebrain and the brainstem cholinergic systems. The effects of chronic alcohol consumption on the basal forebrain cholinergic nuclei have been investigated extensively, but there is only one study that has examined those effects on the brainstem cholinergic nuclei. The last one comprises the pedunculopontine tegmental (PPT) and the laterodorsal tegmental (LDT) nuclei, which are known to give origin to the main cholinergic projection to the ventral tegmental area, a key brain region of the neural circuit, the mesocorticolimbic system, that mediates several behavioral and physiological processes, including reward.

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Objective: The purpose of this study was to clarify the morphology of the insular cortex focusing not only on the shape of the insula, but also on sulcal and gyral organization.

Patients And Methods: Sixty formalin-fixed adult brain hemispheres had their insula exposed and photographed. The dimensions of each gyrus and sulcus were measured using an image analysis software.

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A recent study reported that the integrity of the nucleus of the lateral olfactory tract (nLOT) is required for normal olfaction and for the display of odor-driven behaviors that are critical for species survival and reproduction. In addition to being bi-directionally connected with a key element of the neural circuitry that mediates stress response, the basolateral nucleus of the amygdala, the nLOT is a potential target for glucocorticoids as its cells express glucocorticoid receptors. Herein, we have addressed this hypothesis by exploring, first, if chronic variable stress (CVS) disrupts odor detection and discrimination, and innate olfactory-driven behaviors, namely predator avoidance, sexual behavior and aggression in male rats.

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The nucleus of the lateral olfactory tract (nLOT) is a relatively small component of the cortical pallial amygdala, with peculiar neurogenic, neurochemical and connectivity patterns. Although it has been suggested that it might be involved in non-pheromonal olfactory-guided behaviors, particularly feeding, the functional implications of the nLOT have never been investigated. In view of this fact, we have tackled this subject by performing a series of behavioral tests and by quantifying biological and biochemical parameters in sexually naïve adult male rats that were submitted to bilateral excitotoxic lesions of the nLOT.

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The medial prefrontal cortex (mPFC) has been identified as a critical center for working and long-term memory. In this study, we have examined the expression of neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) in mPFC interneurons and the density of the mPFC cholinergic and dopaminergic innervation in cognitively-impaired aged Wistar rats. We also tested the possibility that the potential age-related changes might rely on insufficient neurotrophic support.

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Several studies have demonstrated the vulnerability of the hippocampal formation (HF) to chronic alcohol consumption and withdrawal. Among the brain systems that appear to be particularly vulnerable to the effects of these conditions are the neuropeptide Y (NPY)-ergic and the cholinergic systems. Because these two systems seem to closely interact in the HF, we sought to study the effects of chronic alcohol consumption (6months) and subsequent withdrawal (2months) on the expression of NPY and on the cholinergic innervation of the rat dentate hilus.

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The olfactory deficits that occur during aging influence the quality of life and have been regarded as a risk factor for malnutrition in the elderly. The nucleus of the lateral olfactory tract (nLOT) is a cortical nucleus of the pallial amygdala that has been implicated in feeding behavior. Here we present quantitative data on the anatomy of the nLOT in the adult rat and on the effects of age on its structure and neurochemistry.

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Lightsticks are artifacts used as attractors in a type of commercial fishery, known as surface longline gear. Despite the excessive use, the contamination risks of these devices have not yet been properly investigated. This research aimed to fill up this gap by determining the chemical composition and the toxicity of lightsticks recently activated, compared to those one year after activation and to the ones collected on the beaches.

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In the course of Parkinson's disease (PD), the enteric nervous system (ENS) and parasympathetic nerves are amongst the structures earliest and most frequently affected by alpha-synuclein pathology. Accordingly, gastrointestinal dysfunction, in particular constipation, is an important non-motor symptom in PD and often precedes the onset of motor symptoms by years. Recent research has shown that intestinal microbiota interact with the autonomic and central nervous system via diverse pathways including the ENS and vagal nerve.

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Caloric restriction is able to delay age-related neurodegenerative diseases and cognitive impairment. In this study, we analyzed the effects of old-onset caloric restriction that started at 18 months of age, in the number of neuropeptide Y (NPY)- and somatostatin (SS)-containing neurons of the hippocampal formation. Knowing that these neuropeptidergic systems seem to be dependent of the cholinergic system, we also analyzed the number of cholinergic varicosities.

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Neuropeptide Y (NPY)- and acetylcholine-containing interneurons of the nucleus accumbens (NAc) seem to play a major role in the rewarding effects of alcohol. This study investigated the relationship between chronic alcohol consumption and subsequent withdrawal and the expression of NPY and acetylcholine in the NAc, and the possible involvement of nerve growth factor (NGF) in mediating the effects of ethanol. Rats ingesting an aqueous ethanol solution over 6months and rats subsequently deprived from ethanol during 2months were used to estimate the total number and the somatic volume of NPY and cholinergic interneurons, and the numerical density of cholinergic varicosities in the NAc.

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Protein deprivation is a detrimental nutritional state that induces several deleterious changes in the rat hippocampal formation. In this study, we compared the effects of protein deprivation in the number of parvalbumin (PV)-immunoreactive and calretinin (CR)-immunoreactive interneurons of the dentate gyrus, which are involved in the control of calcium homeostasis and fine tuning of the hippocampal circuits. Two month-old rats were randomly assigned to control and low-protein diet groups.

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