- Developmental trajectories of the human embryologic brain regions. [Journal Article]
- NLNeurosci Lett 2019 Jun 19; 708:134342
- Vertebrate brains commonly consist of five basic embryologic anatomical regions: telencephalon; diencephalon; mesencephalon; metencephalon; and myelencephalon. The proportions of these regions vary w…
Vertebrate brains commonly consist of five basic embryologic anatomical regions: telencephalon; diencephalon; mesencephalon; metencephalon; and myelencephalon. The proportions of these regions vary widely across species and developmental stages. Investigation of their growth trajectories, therefore, has the potential to provide an understanding of the substrates of inter-species variation in neuroanatomy and function. To investigate the volumetric growth trajectories, structural magnetic resonance imaging (MRI) scans obtained from 618 healthy children (334 boys, 284 girls; ages 3-17 years old) were parcellated into five regions for the volume quantification. The sex- and region-specific growth trajectories were identified, and the most active growth was seen in the mesencephalon for both boys and girls. Whether similar regional growth patterns are seen in other species, or whether such patterns are related to evolution, are important questions that must be elucidated in the future.
- Brain leptin reduces liver lipids by increasing hepatic triglyceride secretion and lowering lipogenesis. [Journal Article]
- NCNat Commun 2019 06 20; 10(1):2717
- Hepatic steatosis develops when lipid influx and production exceed the liver's ability to utilize/export triglycerides. Obesity promotes steatosis and is characterized by leptin resistance. A role of…
Hepatic steatosis develops when lipid influx and production exceed the liver's ability to utilize/export triglycerides. Obesity promotes steatosis and is characterized by leptin resistance. A role of leptin in hepatic lipid handling is highlighted by the observation that recombinant leptin reverses steatosis of hypoleptinemic patients with lipodystrophy by an unknown mechanism. Since leptin mainly functions via CNS signaling, we here examine in rats whether leptin regulates hepatic lipid flux via the brain in a series of stereotaxic infusion experiments. We demonstrate that brain leptin protects from steatosis by promoting hepatic triglyceride export and decreasing de novo lipogenesis independently of caloric intake. Leptin's anti-steatotic effects are generated in the dorsal vagal complex, require hepatic vagal innervation, and are preserved in high-fat-diet-fed rats when the blood brain barrier is bypassed. Thus, CNS leptin protects from ectopic lipid accumulation via a brain-vagus-liver axis and may be a therapeutic strategy to ameliorate obesity-related steatosis.
- [Acute medullary infarct: a still little know diagnosis with a poor prognosis]. [Case Reports]
- PAPan Afr Med J 2018; 31:85
- Medullary infarct is still little known influencing the short-term vital and functional prognosis of patients. Medullary vascularization is one of the most complex in the body due to the significant …
Medullary infarct is still little known influencing the short-term vital and functional prognosis of patients. Medullary vascularization is one of the most complex in the body due to the significant number of arteries that contribute to it. Our knowledge is still limited due to the scarcity of vascular medullary accidents and to low accessibility of medullary vessels during assessments. We report the case of a 62-year old patient with type 2 diabetes and a 13-year history of oral antidiabetic treatment who had been followed-up for psoriasis for 4 years. He presented to hospital in the night with his son due to acute onset of upper limb deficit. This deficit was preceded by acute onset of neck pain during his daily prayer. On admission, the patient was conscious, arterial pressure 120/86mmhg, heart rate 89 beat/min, afebrile. Clinical examination showed flaccid brachial diplegia. There was no sensory disorder or sphincteric disorder and cranial nerve examination was normal. Emergency medullary MRI was performed which showed T2 hyperintense signal and "snake-eyes"-like bilateral central dissemination (A and B). Etiological assessment showed therosclerotic patches at the origin of the left internal carotid artery. The diagnosis of myocardial infarct associated with medullary fibrocartilaginous embolism was retained. Functional rehabilitation was started early as well as treatment with platelet aggregation inhibiting drugs.
- Case report: an area postrema syndrome revealing a neuromyelitis optica spectrum disorder associated with central nervous system tuberculosis in a young Togolese (black African) woman. [Case Reports]
- BNBMC Neurol 2019 Apr 10; 19(1):58
- CONCLUSIONS: The recognition of an APS is an additional challenge for the diagnosis of NMOSDs, especially in countries with limited resources. CNS tuberculosis must be tested when faced with an NMOSD because it seems to be a major cause.
- An Isolated Unilateral Pontomedullary Lesion Due to An Intracranial Dural Arteriovenous Fistula Mimicking A Brain Tumor - Case and Review. [Case Reports]
- JNJ Nippon Med Sch 2019; 86(1):48-54
- Intracranial dural arteriovenous fistula (DAVF) with perimedullary venous drainage may cause brainstem swelling and represent a diagnostic challenge. A 66-year-old man presented to the emergency room…
Intracranial dural arteriovenous fistula (DAVF) with perimedullary venous drainage may cause brainstem swelling and represent a diagnostic challenge. A 66-year-old man presented to the emergency room with recurrent vertigo, minimal truncal ataxia with a wide-based gait, and a slightly impaired tandem gait. Brain magnetic resonance imaging (MRI) revealed a hyperintense lesion in the left pontomedullary area on T2-weighted images (T2WIs) with partial gadolinium enhancement, but without increased signals on diffusion-weighted images. Abnormal serpentine flow void vessels surrounding the medulla and upper cervical spinal cord were initially overlooked but discovered later. An angiogram revealed DAVF with feeders from the right occipital artery and the meningeal branch of the right distal vertebral artery with drainage into the anterior medullary venous system and the perimedullary veins. The patient underwent a successful transarterial endovascular embolization and improved gradually. A brain MRI at 3-month follow-up revealed a residual hyperintense signal on the T2WIs in the left lower medulla. Six cases of patients exhibiting DAVF with isolated unilateral brainstem swelling from the literature were reviewed. Isolated unilateral brainstem swelling due to intracranial DAVF with perimedullary venous drainage is extremely rare and might mimic a tumor on MRI. Abnormal serpentine flow void vessels on the surface of the brainstem or spinal cord are crucial diagnostic clues.
- Seronegative neuromyelitis optica spectrum disorder: severe polysymptomatic presentation with successful treatment response. [Case Reports]
- BCBMJ Case Rep 2019 Mar 16; 12(3)
- We report the case of a 50-year-old caucasian man presenting with lumbar pain, bilateral ataxia, central facial palsy, ophthalmoparesis and urinary retention. Cerebral MRI hinted a hyperintensity of …
We report the case of a 50-year-old caucasian man presenting with lumbar pain, bilateral ataxia, central facial palsy, ophthalmoparesis and urinary retention. Cerebral MRI hinted a hyperintensity of the medulla oblongata and cervical medulla suggestive of myelitis. Cerebrospinal fluid displayed lymphocytic pleocytosis and elevated protein concentration. Without the possibility to rule out an infectious or inflammatory aetiology, antibiotics and corticosteroids were started. Nevertheless, neurological status deteriorated with loss of muscle strength and left eye amaurosis. A neuroaxis MRI exhibited encephalomyelitis with signal abnormalities involving the pons, medulla oblongata, left optic nerve and cervicodorsal medulla. Although negative for aquaporin-4-IgG antibodies, the patient fulfilled criteria for seronegative neuromyelitis optica spectrum disorder with the presence of multiple core clinical characteristics. Through early institution of corticosteroids, plasma exchange and rituximab, good functional recovery was achieved (Expanded Disability Status Scale score of 2). However, left eye amaurosis persisted despite salvage therapy with intravenous immunoglobulin.
- Primary leptomeningeal gliomatosis in a domestic shorthaired cat. [Case Reports]
- JVJ Vet Diagn Invest 2019; 31(1):94-97
- A 15-y-old neutered male domestic shorthaired cat was presented with a 16-d history of hindlimb paralysis in conjunction with 1-wk duration of inappetence and lethargy. Given intractable clinical sig…
A 15-y-old neutered male domestic shorthaired cat was presented with a 16-d history of hindlimb paralysis in conjunction with 1-wk duration of inappetence and lethargy. Given intractable clinical signs, development of seizures, and poor prognosis, euthanasia was elected. Gross examination revealed mild, chronic, multifocal intervertebral disk disease; however, no gross abnormalities were noted in the spinal cord. Histologic examination of the cervical, thoracic, and lumbar spinal cord and the myelencephalon revealed diffuse and variable expansion of the meninges by sheets of neoplastic round-to-polygonal cells. The cells formed sheets and clusters, supported by a variably eosinophilic, fibrillar-to-basophilic, homogeneous matrix, and contained a small amount of eosinophilic cytoplasm. The nuclei were round with finely stippled to hyperchromatic chromatin and 1-2 small nucleoli. Mild white matter degeneration was present in the dorsal and ventral funiculi multifocally throughout the spinal cord, but was most severe in the ventral lumbar sections. Immunohistochemistry revealed strong intranuclear immunoreactivity for Olig2, and intracytoplasmic immunoreactivity for glial fibrillary acidic protein, MAP2, and vimentin in the neoplastic glial cells. To our knowledge, primary leptomeningeal gliomatosis has not been reported previously in a cat.
- Dynamic changes in CGRP, PACAP, and PACAP receptors in the trigeminovascular system of a novel repetitive electrical stimulation rat model: Relevant to migraine. [Journal Article]
- MPMol Pain 2019 Jan-Dec; 15:1744806918820452
- Migraine is the seventh most disabling disorder globally, with prevalence of 11.7% worldwide. One of the prevailing mechanisms is the activation of the trigeminovascular system, and calcitonin gene-r…
Migraine is the seventh most disabling disorder globally, with prevalence of 11.7% worldwide. One of the prevailing mechanisms is the activation of the trigeminovascular system, and calcitonin gene-related peptide (CGRP) is an important therapeutic target for migraine in this system. Recent studies suggested an emerging role of pituitary adenylate cyclase-activating peptide (PACAP) in migraine. However, the relation between CGRP and PACAP and the role of PACAP in migraine remain undefined. In this study, we established a novel repetitive (one, three, and seven days) electrical stimulation model by stimulating dura mater in conscious rats. Then, we determined expression patterns in the trigeminal ganglion and the trigeminal nucleus caudalis of the trigeminovascular system. Electrical stimulation decreased facial mechanical thresholds, and the order of sensitivity was as follows: vibrissal pad >inner canthus >outer canthus (P < 0.001). The electrical stimulation group exhibited head-turning and head-flicks (P < 0.05) nociceptive behaviors. Importantly, electrical stimulation increased the expressions of CGRP, PACAP, and the PACAP-preferring type 1 (PAC1) receptor in both trigeminal ganglion and trigeminal nucleus caudalis (P < 0.05). The expressions of two vasoactive intestinal peptide (VIP)-shared type 2 (VPAC1 and VPAC2) receptors were increased in the trigeminal ganglion, whereas in the trigeminal nucleus caudalis, their increases were peaked on Day 3 and then decreased by Day 7. PACAP was colocalized with NEUronal Nuclei (NeuN), PAC1, and CGRP in both trigeminal ganglion and the trigeminal nucleus caudalis. Our results demonstrate that the repetitive electrical stimulation model can simulate the allodynia during the migraine chronification, and PACAP plays a role in the pathogenesis of migraine potentially via PAC1 receptor.
- Regenerative Failure Following Rat Neonatal Chorda Tympani Transection is Associated with Geniculate Ganglion Cell Loss and Terminal Field Plasticity in the Nucleus of the Solitary Tract. [Journal Article]
- NNeuroscience 2019 03 15; 402:66-77
- Neural insult during development results in recovery outcomes that vary dependent upon the system under investigation. Nerve regeneration does not occur if the rat gustatory chorda tympani nerve is s…
Neural insult during development results in recovery outcomes that vary dependent upon the system under investigation. Nerve regeneration does not occur if the rat gustatory chorda tympani nerve is sectioned (CTX) during neonatal (≤P10) development. It is unclear how chorda tympani soma and terminal fields are affected after neonatal CTX. The current study determined the impact of neonatal CTX on chorda tympani neurons and brainstem gustatory terminal fields. To assess terminal field volume in the nucleus of the solitary tract (NTS), rats received CTX at P5 or P10 followed by chorda tympani label, or glossopharyngeal (GL) and greater superficial petrosal (GSP) label as adults. In another group of animals, terminal field volumes and numbers of chorda tympani neurons in the geniculate ganglion (GG) were determined by labeling the chorda tympani with DiI at the time of CTX in neonatal (P5) and adult (P50) rats. There was a greater loss of chorda tympani neurons following P5 CTX compared to adult denervation. Chorda tympani terminal field volume was dramatically reduced 50 days after P5 or P10 CTX. Lack of nerve regeneration after neonatal CTX is not caused by ganglion cell death alone, as approximately 30% of chorda tympani neurons survived into adulthood. Although the total field volume of intact gustatory nerves was not altered, the GSP volume and GSP-GL overlap increased in the dorsal NTS after CTX at P5, but not P10, demonstrating age-dependent plasticity. Our findings indicate that the developing gustatory system is highly plastic and simultaneously vulnerable to injury.
New Search Next
- Melanin-concentrating hormone does not modulate serotonin release in primary cultures of fetal raphe nucleus neurons. [Journal Article]
- NNeuropeptides 2019; 74:70-81
- Melanin-concentrating hormone (MCH) is a neuropeptide present in neurons located in the hypothalamus that densely innervate serotonergic cells in the dorsal raphe nucleus (DRN). MCH administration in…
Melanin-concentrating hormone (MCH) is a neuropeptide present in neurons located in the hypothalamus that densely innervate serotonergic cells in the dorsal raphe nucleus (DRN). MCH administration into the DRN induces a depressive-like effect through a serotonergic mechanism. To further understand the interaction between MCH and serotonin, we used primary cultured serotonergic neurons to evaluate the effect of MCH on serotonergic release and metabolism by HPLC-ED measurement of serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) levels. We confirmed the presence of serotonergic neurons in the E14 rat rhombencephalon by immunohistochemistry and showed for the first time evidence of MCHergic fibers reaching the area. Cultures obtained from rhombencephalic tissue presented 2.2 ± 0.7% of serotonergic and 48.9 ± 5.4% of GABAergic neurons. Despite the low concentration of serotonergic neurons, we were able to measure basal cellular and extracellular levels of 5-HT and 5-HIAA without the addition of any serotonergic-enhancer drug. As expected, 5-HT release was calcium-dependent and induced by depolarization. 5-HT extracellular levels were significantly increased by incubation with serotonin reuptake inhibitors (citalopram and nortriptyline) and a monoamine-oxidase inhibitor (clorgyline), and were not significantly modified by a 5-HT1A autoreceptor agonist (8-OHDPAT). Even though serotonergic cells responded as expected to these pharmacological treatments, MCH did not induce significant modifications of 5-HT and 5-HIAA extracellular levels in the cultures. Despite this unexpected result, we consider that assessment of 5-HT and 5-HIAA levels in primary serotonergic cultures may be an adequate approach to study the effect of other drugs and modulators on serotonin release, uptake and turnover.