-
Journal of Computer Assisted TomographyThe aims of the study are to explore the morphological changes of olfactory bulb (OB) and olfactory sulcus in COVID-19 patients with associated olfactory dysfunction...
OBJECTIVES
The aims of the study are to explore the morphological changes of olfactory bulb (OB) and olfactory sulcus in COVID-19 patients with associated olfactory dysfunction (OD) by measuring the OB volume (OBV) and olfactory sulcus depth (OSD) and to compare the measurement values with those of healthy individuals.
METHODS
Between March 2020 and January 2022, 31 consecutive hospitalized patients with a diagnosis of COVID-19 with anosmia and hyposmia who underwent brain magnetic resonance imaging and 35 normosmic control individuals were retrospectively included in the study. Bilateral OBV and OSD were measured and shape of the OB was determined based on the consensus by a neuroradiologist and an otorrhynolaryngologist.
RESULTS
The mean measurements for the right and the left sides for OBV (38 ± 8.5 and 37.1 ± 8.4, respectively) and OSD (7.4 ± 0.1 and 7.4 ± 1.0 mm, respectively) were significantly lower in COVID-19 patients with OD than those in control group (for the right and the left sides mean OBV 56.3 ± 17.1 and 49.1 ± 13.5, respectively, and mean OSD 9.6 ± 0.8 and 9.4 ± 0.8 mm, respectively). Abnormally shaped OB (lobulated, rectangular, or atrophic) were higher in patient group than those of controls.For the optimal cutoff values, OBV showed sensitivity and specificity values of 90.32% and, 57.14%, for the right, and 87.1% and 62.86% for the left side, respectively (area under the curve, 0.819 and 0.780). Olfactory sulcus depth showed sensitivity and specificity values of 90.32% and 94.29%, for the right, and 96.77% and 85.71%, for the left side, respectively (area under the curve, 0.960 and 0.944).
CONCLUSIONS
Decrease in OBV and OSD measurements in COVID-19 patients with OD at the early chronic stage of the disease supports direct damage to olfactory neuronal pathways and may be used to monitor olfactory nerve renewal while returning back to normal function.
Topics: Humans; Retrospective Studies; Olfactory Bulb; COVID-19; Olfaction Disorders; Magnetic Resonance Imaging
PubMed: 37876233
DOI: 10.1097/RCT.0000000000001559 -
Frontiers in Physiology 2023Nervous systems of vertebrates and invertebrates show a common modular theme in the flow of information for cost-benefit decisions. Sensory inputs are incentivized by...
Nervous systems of vertebrates and invertebrates show a common modular theme in the flow of information for cost-benefit decisions. Sensory inputs are incentivized by integrating stimulus qualities with motivation and memory to affect appetitive state, a system of homeostatic drives, and labelled for directionality. Appetitive state determines action responses from a repertory of possibles and transmits the decision to a premotor system that frames the selected action in motor arousal and appropriate postural and locomotion commands. These commands are then sent to the primary motor pattern generators controlling the motorneurons, with feedback at each stage. In the vertebrates, these stages are mediated by forebrain pallial derivatives for incentive and directionality (olfactory bulb, cerebral cortex, pallial amygdala, ) interacting with hypothalamus (homeostasis, motivation, and reward) for action selection in the forebrain basal ganglia, the mid/hindbrain reticular formation as a premotor translator for posture, locomotion, and arousal state, and the spinal cord and cranial nuclei as primary motor pattern generators. Gastropods, like the predatory sea slug , show a similar organization but with differences that suggest how complex brains evolved from an ancestral soft-bodied bilaterian along with segmentation, jointed skeletons, and complex exteroceptors. Their premotor feeding network combines functions of hypothalamus and basal ganglia for homeostasis, motivation, presumed reward, and action selection for stimulus approach or avoidance. In , the premotor analogy to the vertebrate reticular formation is the bilateral "A-cluster" of cerebral ganglion neurons that controls posture, locomotion, and serotonergic motor arousal. The A-cluster transmits motor commands to the pedal ganglia analogs of the spinal cord, for primary patterned motor output. Apparent pallial precursors are not immediately evident in 's central nervous system, but a notable candidate is a subepithelial nerve net in the peripheral head region that integrates chemotactile stimuli for incentive and directionality. Evolutionary centralization of its computational functions may have led to the olfaction-derived pallial forebrain in the ancestor's vertebrate descendants and their analogs in arthropods and annelids.
PubMed: 37854468
DOI: 10.3389/fphys.2023.1263453 -
Therapeutic Advances in Chronic Disease 2023Complementary and alternative medicine (CAM) interventions are growing in popularity as possible treatments for long COVID symptoms. However, comprehensive analysis of... (Review)
Review
BACKGROUND
Complementary and alternative medicine (CAM) interventions are growing in popularity as possible treatments for long COVID symptoms. However, comprehensive analysis of current evidence in this setting is still lacking.
OBJECTIVE
This study aims to review existing published studies on the use of CAM interventions for patients experiencing long COVID through a systematic review.
DESIGN
Systematic review of randomized controlled trials (RCTs).
METHODS
A comprehensive electronic literature search was performed in multiple databases and clinical trial registries from September 2019 to January 2023. RCTs evaluating efficacy and safety of CAM for long COVID were included. Methodological quality of each included trial was appraised with the Cochrane 'risk of bias' tool. A qualitative analysis was conducted due to heterogeneity of included studies.
RESULTS
A total of 14 RCTs with 1195 participants were included in this review. Study findings demonstrated that CAM interventions could benefit patients with long COVID, especially those suffering from neuropsychiatric disorders, olfactory dysfunction, cognitive impairment, fatigue, breathlessness, and mild-to-moderate lung fibrosis. The main interventions reported were self-administered transcutaneous auricular vagus nerve stimulation, neuro-meditation, dietary supplements, olfactory training, aromatherapy, inspiratory muscle training, concurrent training, and an online breathing and well-being program.
CONCLUSION
CAM interventions may be effective, safe, and acceptable to patients with symptoms of long COVID. However, the findings from this systematic review should be interpreted with caution due to various methodological limitations. More rigorous trials focused on CAM for long COVID are warranted in the future.
PubMed: 37841213
DOI: 10.1177/20406223231204727 -
Cureus Sep 2023Background Abnormal sensations were frequently experienced by patients who received irradiation of the brain or head and neck region. We have previously suggested...
Background Abnormal sensations were frequently experienced by patients who received irradiation of the brain or head and neck region. We have previously suggested correlations with irradiation of the nasal cavity and retina. Purpose We performed a retrospective dose-volume histogram analysis focused on the brain and head and neck tumor to examine the relationship between these abnormal sensations and the details of irradiation. Methods Multivariate logistic regression models were applied for the presence or absence of light flash and odor. Gender, age, radiotherapy method (proton beam therapy vs. photon radiotherapy), dose of retina, optic nerve, chiasmatic gland, pituitary, nasal cavity, oral cavity, frontal lobe, parietal lobe, occipital lobe, temporal lobe, amygdala, and hippocampus were set as candidates of explanatory variables. Results Light flash and odor during radiotherapy have been suggested to be associated with younger age and retina and nasal cavity irradiation. Multivariate analyses including dose-volume histograms indicated that light flash was related to age, chiasmatic gland irradiation, and pituitary dose, and odor was related to age and nasal cavity irradiation. Conclusion Our results indicate that light flash during radiotherapy is caused by irradiation of the visual pathway and that odor is caused by irradiation of the nasal cavity or olfactory bulb.
PubMed: 37809274
DOI: 10.7759/cureus.44790 -
Cureus Sep 2023A collision tumor complex is composed of at least two different tumors, benign or malignant, with at least two different histopathological features located adjacent to...
A collision tumor complex is composed of at least two different tumors, benign or malignant, with at least two different histopathological features located adjacent to each other in the exact anatomical localization. Pathologies such as meningiomas, pituitary adenomas, gliomas, and schwannomas may be involved in a collision tumor complex. However, co-occurrence of pituitary adenomas and meningiomas as skull base collision tumors is rare. Here, we present a 65-year-old male patient who presented with olfactory groove meningioma and non-functioning pituitary adenoma as a collision tumor. The patient was admitted with a headache and right-sided vision loss. The patient's first neurologic examination was consistent with temporal anopsia in the right eye. Subsequent contrast-enhanced cranial MRI revealed a 65x55x40 mm heterogeneously contrast-enhanced lesion in the anterior skull base extending from the sellar region to the corpus callosum. Because of the tumor size, a two-staged operation was planned. First, the tumor was partially excised via a right frontal craniotomy with a transcranial approach, and the tumor in the sellar region was left as a residue. The pathology reports after the first surgery showed pituitary adenoma and meningeal epithelial type meningioma (WHO Grade I). The residual tumor tissue was resected seven months later via an endoscopic endonasal approach, except for the part that invaded the right anterior cerebral artery. The optic nerve was decompressed. The patient was then referred to the radiation oncology clinic for radiosurgery. Collision tumors should be considered in the differential diagnosis in preoperative evaluation and surgical planning when heterogeneously contrast-enhanced areas significantly localized adjacent to each other are seen on cranial MRI. On the other hand, when the surgeon encounters sudden changes in the appearance or consistency of the tumor during the surgery, they should suspect these tumor complexes. The diagnosis of collision tumors is quite challenging but is of great importance regarding the patient's need for postoperative radiation therapy or the recurrence characteristics of tumors. However, more studies are needed on these complexes' etiology, surgical planning, and postoperative management.
PubMed: 37809125
DOI: 10.7759/cureus.44710 -
The Canadian Journal of Neurological... Oct 2023The homeless population experience significant inequalities in health, and there is an increasing appreciation of the potential of lifestyle factors in the development...
BACKGROUND
The homeless population experience significant inequalities in health, and there is an increasing appreciation of the potential of lifestyle factors in the development of neurodegenerative diseases, including Parkinson's disease. We performed a study on the prevalence and distribution of pathological alpha-synuclein deposition throughout the central and peripheral nervous systems in a homeless population.
METHODS
Forty-four homeless individuals consecutively available for autopsy were recruited. Immunohistochemistry was performed using 5G4 antibody recognizing disease-associated forms of alpha-synuclein, complemented by phospho-synuclein antibody on autopsy tissues collected from 18 regions of the brain and spinal cord, as well as the right and left olfactory bulb, the cauda equina, the extramedullary portion of the vagus nerve, and 27 sites of peripheral organs.
RESULTS
The study cohort consisted of 38 males and 6 females, median age 58 years (range 32-67). Lewy-related pathology was present in the brains of three male cases. One showed Braak stage 2 (60 years old), and two stage 4 (56 and 59 years old). One of the Braak stage 4 cases had Lewy-related pathology in the spinal cord, the cauda equina, and the extramedullary portion of the vagus nerve. Examination of 27 sites of peripheral organs found that all three cases with Lewy-related pathology present in the brain were devoid of peripheral organ alpha-synuclein pathology. Multiple system-type alpha-synuclein pathology was not found.
CONCLUSION
Our study, representing a snapshot of the homeless population that came to autopsy, suggests that alpha-synuclein pathology is prevalent in the homeless supporting further study of this vulnerable population.
PubMed: 37793895
DOI: 10.1017/cjn.2023.291 -
Advanced Science (Weinheim,... Nov 2023Addressing the challenge of promoting directional axonal regeneration in a hostile astrocytic scar, which often impedes recovery following spinal cord injury (SCI),...
A Novel Magnetic Responsive miR-26a@SPIONs-OECs for Spinal Cord Injury: Triggering Neural Regeneration Program and Orienting Axon Guidance in Inhibitory Astrocytic Environment.
Addressing the challenge of promoting directional axonal regeneration in a hostile astrocytic scar, which often impedes recovery following spinal cord injury (SCI), remains a daunting task. Cell transplantation is a promising strategy to facilitate nerve restoration in SCI. In this research, a pro-regeneration system is developed, namely miR-26a@SPIONs-OECs, for olfactory ensheathing cells (OECs), a preferred choice for promoting nerve regeneration in SCI patients. These entities show high responsiveness to external magnetic fields (MF), leading to synergistic multimodal cues to enhance nerve regeneration. First, an MF stimulates miR-26a@SPIONs-OECs to release extracellular vesicles (EVs) rich in miR-26a. This encourages axon growth by inhibiting PTEN and GSK-3β signaling pathways in neurons. Second, miR-26a@SPIONs-OECs exhibit a tendency to migrate and orientate along the direction of the MF, thereby potentially facilitating neuronal reconnection through directional neurite elongation. Third, miR-26a-enriched EVs from miR-26a@SPIONs-OECs can interact with host astrocytes, thereby diminishing inhibitory cues for neurite growth. In a rat model of SCI, the miR-26a@SPIONs-OECs system led to significantly improved morphological and motor function recovery. In summary, the miR-26a@SPIONS-OECs pro-regeneration system offers innovative insights into engineering exogenous cells with multiple additional cues, augmenting their efficacy for stimulating and guiding nerve regeneration within a hostile astrocytic scar in SCI.
Topics: Rats; Humans; Animals; Astrocytes; Cicatrix; Axon Guidance; Glycogen Synthase Kinase 3 beta; Nerve Regeneration; Spinal Cord Injuries; Magnetic Phenomena; MicroRNAs
PubMed: 37789583
DOI: 10.1002/advs.202304487 -
Cell Transplantation 2023In the past decades, the properties of olfactory ensheathing cells (OECs) have been widely investigated. Studies have shown that transplantation of OECs cultured from...
In the past decades, the properties of olfactory ensheathing cells (OECs) have been widely investigated. Studies have shown that transplantation of OECs cultured from the olfactory bulb mediates axonal regeneration, remyelination and restores lost functions in experimental central nervous system (CNS) injury models. Autologously sourcing the cells from the nasal mucosa or the olfactory bulb to treat patients with spinal cord injuries would be ideal, but the cell yield achieved may be inadequate to cover the surface area of the lesions typically encountered in human spinal cord contusion injuries. Therefore, banking allogenic cryopreserved olfactory bulb cells from donors or generating cell lines could provide a marked increase in cell stock available for transplantation. This study is undertaken in two control and two intervention groups. The control groups have lesions alone and lesions with collagen gel but without cells. The intervention groups have either transplantation of primary cultured olfactory bulb OECs (bOECs) encapsulated in collagen gel or cryopreserved bulb OECs (CbOECs) encapsulated in collagen gel. Here, we report that transplantation of cryopreserved rat bOECs encapsulated in collagen restored the loss of function in a vertical climbing test in a unilateral C6-T1 dorsal root injury model. The loss of function returns in 80% of rats with injuries in about 3 weeks comparable to that we observed after transplantation of primary cultured bOECs. The regeneration axons induced by the transplant are identified by neurofilament antibodies and ensheathed by OECs. Our results indicate that cryopreserved OECs retain their properties of inducing axon regeneration and restoring loss of function in the experimental model. This is a step forward to translate the research into future clinical applications.
Topics: Rats; Humans; Animals; Axons; Cell Transplantation; Nerve Regeneration; Spinal Cord Injuries; Olfactory Bulb; Collagen
PubMed: 37771302
DOI: 10.1177/09636897231199319 -
Medicina (Kaunas, Lithuania) Aug 2023: Hypo/anosmia is a characteristic symptom of COVID-19 infection. The aim of this study is to investigate the time of smell recovery and to identify a possible order of... (Observational Study)
Observational Study
: Hypo/anosmia is a characteristic symptom of COVID-19 infection. The aim of this study is to investigate the time of smell recovery and to identify a possible order of perception recovery of different odors in COVID-19 patients. : A prospective observational study was conducted on not hospitalized COVID-19 patients, selected according to eligible criteria. The study was approved by the Ethical Committee. A questionnaire formulated by our team was submitted to patients in order to know the duration of the hypo/anosmia and hypo/ageusia and the order of odor recovery: vanillin (mixed olfactory/gustatory substances), phenyl ethyl alcohol (rosewater) (pure olfactory substances), eucalyptol (mixed olfactory/trigeminal substances), and eugenol (mixed olfactory/trigeminal/gustatory substances). : 181 patients were included. Hypo/ageusia and hypo/anosmia lasted on average 10.25 (±8.26) and 12.8 (±8.80) days, respectively. The most frequent odor recovery sequence was: (1) phenyl ethyl alcohol; (2) eucalyptol; (3) vanillin; and (4) eugenol. In COVID-19 patients, hypo/anosmia occurs more often in women and at a young age. : This preliminary investigation highlighted novel data: there is a chronological order in perception recovery of different olfactory substances and, therefore, in the restoration of the various sensitive nerve pathways involved in the sense of smell.
Topics: Humans; Female; Smell; Anosmia; Ageusia; Eucalyptol; Eugenol; COVID-19; Phenylethyl Alcohol
PubMed: 37763630
DOI: 10.3390/medicina59091511 -
Life Sciences Nov 2023Evidence indicates accumulating Aβ peptides in brain activates immune responses in neuronal and peripheral system, which may collaboratively influence pathogenesis of...
AIMS
Evidence indicates accumulating Aβ peptides in brain activates immune responses in neuronal and peripheral system, which may collaboratively influence pathogenesis of Alzheimer's disease (AD). We aim to investigate whether regulating intestinal innate immune signaling ameliorates Aβ-induced impairments in Drosophila melanogaster.
MAIN METHODS
Quantitative polymerase chain reaction (qPCR) was used to observe expression changes of innate immune responses related genes in brain and in gut under the circumstance of Aβ overexpressing in nerve system. Aversive olfactory conditioning and survival assay were used to investigate effects of modulating Attacin-A (AttA) and Dpitercin-A (DptA). Fluorometric assays of respiratory burst activity was introduced to explore whether reducing oxidative stress enables overexpressing intestinal AttA and DptA to reverse Aβ-induced deficits.
KEY FINDINGS
In vivo genetic analysis revealed that accumulating Aβ42 in neurons modulates innate immune signaling of the IMD pathway both in the brain and in the gut. Increased expression levels of the intestinal AttA and DptA improved learning performance and extended the lifespan of Aβ42 flies. The administration of apramycin led to alleviations of Aβ-induced behavioral changes, indicating that gram-negative bacteria are associated with the development of Aβ-induced pathologies. Further analysis showed that the neural expression of Aβ42 increased oxidative stress in the gut, which disrupted intestinal integrity and decreased learning performance. In addition, increased levels of AMPs targeting gram-negative bacteria and antioxidants reduced oxidative stress in the gut and reversed Aβ-induced behavioral damage.
SIGNIFICANCE
These findings suggest that innate immune responses in the gut play a pivotal role in modulating Aβ-induced pathologies.
Topics: Animals; Drosophila; Drosophila melanogaster; Peptide Fragments; Disease Models, Animal; Amyloid beta-Peptides; Alzheimer Disease; Brain
PubMed: 37741318
DOI: 10.1016/j.lfs.2023.122118