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Journal of Neurology Apr 2024Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory syndrome with characteristic clinical,... (Review)
Review
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory syndrome with characteristic clinical, radiological, and pathological features, and can be effectively treated with corticosteroid-based immunotherapies. The exact pathogenesis of CLIPPERS remains unclear, and specific diagnostic biomarkers are not available. According to the 2017 diagnostic criteria, probable CLIPPERS should be considered in middle-aged patients with subacute onset of pontocerebellar symptoms and typical punctuate and curvilinear gadolinium enhancement lesions ("salt-and-pepper" appearance) located in the hindbrain (especially pons) on magnetic resonance imaging. In addition, CLIPPERS-mimics, such as central nervous system (CNS) lymphoma, and several antibody-associated autoimmune CNS diseases (e.g., myelin oligodendrocyte glycoprotein antibody-associated disease, autoimmune glial fibrillary acidic protein astrocytopathy, and anti-N-methyl-D-aspartate receptor encephalitis), should be extensively excluded. The prerequisite for definite CLIPPERS is the perivascular T-cell-predominant inflammatory infiltration observed on pathological analysis. A biopsy is strongly suggested when clinical/radiological red flags are present. Most patients with CLIPPERS respond well to corticosteroids and have a good prognosis. Long-term low-dose corticosteroid maintenance therapy or corticosteroids coupled with immunosuppressants are recommended to prevent the recurrence of the syndrome. The potential progression of CLIPPERS to lymphoma has been suggested in some cases; therefore, at least 2-year clinical and radiological follow-up is essential. Here, we critically review the recent developments and provided an update on the clinical characteristics, diagnostic criteria, differential diagnoses, and therapeutic management of CLIPPERS. We also discuss the current controversies in this context that can be resolved in future research studies.
Topics: Middle Aged; Humans; Contrast Media; Gadolinium; Inflammation; Steroids; Adrenal Cortex Hormones; Magnetic Resonance Imaging; Pons; Central Nervous System Neoplasms; Lymphoma
PubMed: 38286842
DOI: 10.1007/s00415-024-12189-4 -
EBioMedicine Nov 2015The in vivo neural activity of the pons during the perception of affective stimuli has not been studied despite the strong implications of its role in affective...
The in vivo neural activity of the pons during the perception of affective stimuli has not been studied despite the strong implications of its role in affective processing. To examine the activity of the pons during the viewing of affective stimuli, and to verify its functional and structural connectivity with other affective neural correlates, a multimodal magnetic resonance imaging methodology was employed in this study. We observed the in vivo activity of the pons when viewing affective stimuli. Furthermore, small-world connectivity indicated that the functional connectivity (FC) between the pons and the cortico-limbic affective regions was meaningful, with the coefficient λ being positively associated with self-reported emotional reactivity. The FC between the pons and the cortico-limbic-striatal areas was related to self-reported negative affect. Corroborating this finding was the observation that the tract passing through the pons and the left hippocampus was negatively related to self-reported positive affect and positively correlated with emotional reactivity. Our findings support the framework that the pons works conjunctively with the distributed cortico-limbic-striatal systems in shaping individuals' affective states and reactivity. Our work paves the path for future research on the contribution of the pons to the precipitation and maintenance of affective disorders.
Topics: Affect; Brain Mapping; Emotions; Female; Humans; Magnetic Resonance Imaging; Neural Pathways; Pons
PubMed: 26870804
DOI: 10.1016/j.ebiom.2015.10.020 -
The European Journal of Neuroscience Jun 2016We recently showed that orexin expression in sudden infant death syndrome (SIDS) infants was reduced by 21% in the hypothalamus and by 40-50% in the pons as compared...
We recently showed that orexin expression in sudden infant death syndrome (SIDS) infants was reduced by 21% in the hypothalamus and by 40-50% in the pons as compared with controls. Orexin maintains wakefulness/sleeping states, arousal, and rapid eye movement sleep, abnormalities of which have been reported in SIDS. This study examined the effects of two prominent risk factors for SIDS, intermittent hypercapnic hypoxia (IHH) (prone-sleeping) and chronic nicotine exposure (cigarette-smoking), on orexin A (OxA) and orexin B (OxB) expression in piglets. Piglets were randomly assigned to five groups: saline control (n = 7), air control (n = 7), nicotine [2 mg/kg per day (14 days)] (n = 7), IHH (6 min of 7% O2 /8% CO2 alternating with 6-min periods of breathing air, for four cycles) (n = 7), and the combination of nicotine and IHH (N + IHH) (n = 7). OxA/OxB expression was quantified in the central tuberal hypothalamus [dorsal medial hypothalamus (DMH), perifornical area (PeF), and lateral hypothalamus], and the dorsal raphe, locus coeruleus of the pons. Nicotine and N + IHH exposures significantly increased: (i) orexin expression in the hypothalamus and pons; and (ii) the total number of neurons in the DMH and PeF. IHH decreased orexin expression in the hypothalamus and pons without changing neuronal numbers. Linear relationships existed between the percentage of orexin-positive neurons and the area of pontine orexin immunoreactivity of control and exposure piglets. These results demonstrate that postnatal nicotine exposure increases the proportion of orexin-positive neurons in the hypothalamus and fibre expression in the pons, and that IHH exposure does not prevent the nicotine-induced increase. Thus, although both nicotine and IHH are risk factors for SIDS, it appears they have opposing effects on OxA and OxB expression, with the IHH exposure closely mimicking what we recently found in SIDS.
Topics: Animals; Animals, Newborn; Humans; Hypercapnia; Hypothalamus; Hypoxia; Immunohistochemistry; Infant; Male; Neurons; Nicotine; Orexins; Pons; Sudden Infant Death; Swine
PubMed: 27038133
DOI: 10.1111/ejn.13246 -
BMC Biology Jun 2023Based on their anatomical location, rostral projections of nuclei are classified as ascending circuits, while caudal projections are classified as descending circuits....
BACKGROUND
Based on their anatomical location, rostral projections of nuclei are classified as ascending circuits, while caudal projections are classified as descending circuits. Upper brainstem neurons participate in complex information processing and specific sub-populations preferentially project to participating ascending or descending circuits. Cholinergic neurons in the upper brainstem have extensive collateralizations in both ascending and descending circuits; however, their single-cell projection patterns remain unclear because of the lack of comprehensive characterization of individual neurons.
RESULTS
By combining fluorescent micro-optical sectional tomography with sparse labeling, we acquired a high-resolution whole-brain dataset of pontine-tegmental cholinergic neurons (PTCNs) and reconstructed their detailed morphology using semi-automatic reconstruction methods. As the main source of acetylcholine in some subcortical areas, individual PTCNs had abundant axons with lengths up to 60 cm and 5000 terminals and innervated multiple brain regions from the spinal cord to the cortex in both hemispheres. Based on various collaterals in the ascending and descending circuits, individual PTCNs were grouped into four subtypes. The morphology of cholinergic neurons in the pedunculopontine nucleus was more divergent, whereas the laterodorsal tegmental nucleus neurons contained richer axonal branches and dendrites. In the ascending circuits, individual PTCNs innervated the thalamus in three different patterns and projected to the cortex via two separate pathways. Moreover, PTCNs targeting the ventral tegmental area and substantia nigra had abundant collaterals in the pontine reticular nuclei, and these two circuits contributed oppositely to locomotion.
CONCLUSIONS
Our results suggest that individual PTCNs have abundant axons, and most project to various collaterals in the ascending and descending circuits simultaneously. They target regions with multiple patterns, such as the thalamus and cortex. These results provide a detailed organizational characterization of cholinergic neurons to understand the connexional logic of the upper brainstem.
Topics: Brain Stem; Axons; Pons; Brain; Cholinergic Neurons
PubMed: 37280580
DOI: 10.1186/s12915-023-01625-y -
Operative Neurosurgery (Hagerstown, Md.) Jul 2021
Topics: Hemangioma, Cavernous; Humans; Pons
PubMed: 34018002
DOI: 10.1093/ons/opab159 -
Journal of Neurology Oct 2019
Topics: Aged; Humans; Magnetic Resonance Imaging; Male; Multiple System Atrophy; Pons
PubMed: 31254063
DOI: 10.1007/s00415-019-09439-1 -
Spinal Cord Mar 2018Narrative review. (Review)
Review
STUDY DESIGN
Narrative review.
OBJECTIVES
The purpose is to review the organisation of the nerve pathways that control defecation and to relate this knowledge to the deficits in colorectal function after SCI.
METHODS
A literature review was conducted to identify salient features of defecation control pathways and the functional consequences of damage to these pathways in SCI.
RESULTS
The control pathways for defecation have separate pontine centres under cortical control that influence defecation. The pontine centres connect, separately, with autonomic preganglionic neurons of the spinal defecation centres and somatic motor neurons of Onuf's nucleus in the sacral spinal cord. Organised propulsive motor patterns can be generated by stimulation of the spinal defecation centres. Activation of the somatic neurons contracts the external sphincter. The analysis aids in interpreting the consequences of SCI and predicts therapeutic strategies.
CONCLUSIONS
Analysis of the bowel control circuits identifies sites at which bowel function may be modulated after SCI. Colokinetic drugs that elicit propulsive contractions of the colorectum may provide valuable augmentation of non-pharmacological bowel management procedures.
Topics: Colonic Diseases; Disease Management; Female; Humans; Internet; Male; Neural Pathways; Pons; PubMed; Spinal Cord Injuries
PubMed: 29142293
DOI: 10.1038/s41393-017-0026-2 -
Journal of Neurophysiology Aug 2023The anterior lateral motor cortex (ALM) is critical to subsequent correct movements and plays a vital role in predicting specific future movements. Different descending...
The anterior lateral motor cortex (ALM) is critical to subsequent correct movements and plays a vital role in predicting specific future movements. Different descending pathways of the ALM are preferentially involved in different roles in movements. However, the circuit function mechanisms of these different pathways may be concealed in the anatomy circuit. Clarifying the anatomy inputs of these pathways should provide some helpful information for elucidating these function mechanisms. Here, we used a retrograde trans-synaptic rabies virus to systematically generate, analyze, and compare whole brain maps of inputs to the thalamus (TH)-, medulla oblongata (Med)-, superior colliculus (SC)-, and pontine nucleus (Pons)-projecting ALM neurons in C57BL/6J mice. Fifty-nine separate regions from nine major brain areas projecting to the descending pathways of the ALM were identified. Brain-wide quantitative analyses revealed identical whole brain input patterns between these descending pathways. Most inputs to the pathways originated from the ipsilateral side of the brain, with most innervations provided by the cortex and TH. The contralateral side of the brain also sent sparse projections, but these were rare, emanating only from the cortex and cerebellum. Nevertheless, the inputs received by TH-, Med-, SC-, and Pons-projecting ALM neurons had different weights, potentially laying an anatomical foundation for understanding the diverse functions of well-defined descending pathways of the ALM. Our findings provide anatomical information to help elucidate the precise connections and diverse functions of the ALM. Distinct descending pathways of anterior lateral motor cortex (ALM) share common inputs. These inputs are with varied weights. Most inputs were from the ipsilateral side of brain. Preferential inputs were provided by cortex and thalamus (TH).
Topics: Mice; Animals; Motor Cortex; Mice, Inbred C57BL; Pons; Thalamus; Motor Neurons; Neural Pathways
PubMed: 37377198
DOI: 10.1152/jn.00112.2023 -
Hellenic Journal of Nuclear Medicine 2019We aimed to evaluate the association between the availability of serotonin transporter (SERT) measured by ioflupane-DaTSCAN (I-FP-CIT) and imaged by single photon...
OBJECTIVE
We aimed to evaluate the association between the availability of serotonin transporter (SERT) measured by ioflupane-DaTSCAN (I-FP-CIT) and imaged by single photon emission tomography (SPET) and memory function in healthy subjects.
SUBJECTS AND METHODS
Specific binding of I-FP-CIT indicating SERT was achieved using a region of interest analysis. Spherical volumes of interest for midbrain and pons were defined. The cerebellum was chosen as a reference region. Specific binding ratios (SBR) in midbrain and pons representing SERT availability were measured as follows: SBR=(target-cerebellum)/cerebellum. A hundred and eighty-one healthy subjects (117 male, 64 female) were included in this study.
RESULTS
Specific binding ratios of both midbrain (P=0.025) and pons (P=0.006) of males was higher than that of females. None of the SBR showed a correlation with age both in males: (midbrain; P=0.736, pons; P=0.875) and in females (midbrain; P=0.294, pons; P=0.170). In all our cases, SERT availability of midbrain correlated positively with total recall score (rho=0.159, P=0.033), and delayed recall score (rho=0.149, P=0.046). In females, the correlation between SERT availability in midbrain and delayed recall score was significant (rho=0.320, P=0.010), however, not in males (rho=0.112, P=0.229).
CONCLUSION
In conclusion, we demonstrated that SERT availability was associated with memory function in healthy females from the PPMI database. Further studies are needed to clarify underlying mechanisms of this phenomenon.
Topics: Female; Healthy Volunteers; Humans; Male; Memory; Mesencephalon; Middle Aged; Pons; Serotonin Plasma Membrane Transport Proteins; Tomography, Emission-Computed, Single-Photon; Tropanes
PubMed: 31587029
DOI: 10.1967/s002449911055 -
World Neurosurgery Nov 2019Epidermoid cysts are slow-growing extra-axial lesions that account for approximately 1% of all brain tumors. They rarely occur in the brain stem, and those possessing... (Review)
Review
BACKGROUND
Epidermoid cysts are slow-growing extra-axial lesions that account for approximately 1% of all brain tumors. They rarely occur in the brain stem, and those possessing both intra-axial as well as extra-axial components represent an even smaller subset.
CASE DESCRIPTION
We report the unusual manifestation of 2 adult male patients, whose recurrent posterior fossa epidermoid cysts progressively invaded the anterior surface of the pons. Over the years, the patients would present with various complaints of ataxia, diplopia, facial spasms, and hearing loss and underwent several interventions for recurrence. Eventually, the epidermoid cysts progressed to completely split the pons, forming a surgical corridor that was amenable to a posterior approach. We describe the patients' favorable clinical courses, pathologic and neuroradiologic findings, as well as review the literature for similar such cases.
CONCLUSIONS
To the best of our knowledge, there are only 8 other cases of brainstem epidermoid lesions reported in the literature that are presumed to have originated extrinsically and thereafter transgressed the pons. However, we are the first to provide radiographic documentation confirming the progression of the lesions from extra-axial to intraparenchymal. Furthermore, although clinically subtle, we have decided to coin the term "split-pons syndrome" to better define this radiologic entity. Based on the evolution of the epidermoid's growth pattern, the authors propose a delayed posterior approach (telo-velo-tonsillar) to minimize morbidity.
Topics: Brain Diseases; Cerebellopontine Angle; Craniotomy; Epidermal Cyst; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Pons; Postoperative Complications; Surgery, Computer-Assisted; Syndrome; Treatment Outcome
PubMed: 31306846
DOI: 10.1016/j.wneu.2019.07.072