It has been suggested that the role of neurogenic inflammation is to protect the airway from various noxious irritants in inhaled air. Repeated exposure to various irritating stimuli has become very common in daily life. However, the process that occurs in neurogenic inflammation after repeated exposure to irritating stimuli is not yet clearly understood. The aim of this study was to investigate the changes of microvascular leakage in the airways after re-exposure to capsaicin in an experiment using a rat model challenged/rechallenged with capsaicin. Twenty-four Sprague-Dawley rats were divided into four groups : a capsaicin-challenged group (10 microgram/kg of capsaicin, intravenous, n=6) and three capsaicin-rechallenged groups (10 microgram/kg of capsaicin, intravenous, n=6 in each group) corresponding to time intervals of 1, 3, or 6 hours after capsaicin-challenge. The amount of microvascular leakage in the nasal mucosa and trachea of the animal in each group was measured with extravasation of Evans blue dye (30 mg/kg, intravenous) using a spectrophotometer. In the nasal mucosa, a significant enhancement of microvascular leakage with capsaicin-rechallenge was observed at 3 hours after capsaicin-challenge (AVOVAR, * : p<0.01). However, there was no significant changes in the trachea. In conclusion, the protective mechanisms against repeated irritating stimuli in the nasal mucosa and trachea are different. After exposure to a noxious irritant, the airway defense mechanism mediated by an axon reflex in the nose may be up- regulated, while that in the trachea may not be changed.
Animals ; Axons ; Capsaicin* ; Evans Blue ; Irritants ; Models, Animal* ; Nasal Mucosa* ; Neurogenic Inflammation ; Nose ; Rats* ; Rats, Sprague-Dawley ; Reflex ; Trachea

Zika is a re-emerging, mosquito-borne viral infection, which has been recently shown to cause microcephaly and Guillain-Barré syndrome. Since 2015 the number of infected patients has increased significantly in South America. The purpose of this study was to identify the epidemiologic and clinical characteristics of patients with Zika virus (ZIKV) infections in Korea. Patients who had visited areas of risk and tested positive in the ZIKV reverse transcriptase polymerase chain reaction (RT-PCR) in blood, urine, or saliva specimens were included. The first Korean case of ZIKV infection was reported in March 2016, and 14 cases had been reported by October 2016. The median age of the patients was 34 years (19–64 years). Ten patients had been exposed in Southeast Asia and 4 in Latin America. Rash was the most common symptom (92.9%; 13/14), followed by myalgia (50.0%; 7/14), and arthralgia (28.6%, 4/14). There were no neurologic abnormalities and none of the patients was pregnant. Results of biochemical tests were normal. Positivity rates of RT-PCR for ZIKV in serum, urine, and saliva were 53.8%, 100.0%, and 83.3%, respectively in the first week of symptoms. In conclusion, 14 patients with ZIKV infections were reported in Korea by October 2016 and all of them had mild clinical symptoms.
Arthralgia ; Asia, Southeastern ; Epidemiology* ; Exanthema ; Guillain-Barre Syndrome ; Humans ; Korea* ; Latin America ; Microcephaly ; Myalgia ; Reverse Transcriptase Polymerase Chain Reaction ; Saliva ; South America ; Virus Shedding ; Zika Virus*

Autism spectrum disorder (ASD) remains unexplained and untreated despite the high attention of research in recent years. Aside from its various characteristics is the baffling male preponderance over the female population. Using a validated animal model of ASD which is the telomerase reverse transcriptase overexpressing mice (TERT-tg), we conducted ASD-related behavioral assessments and protein expression experiments to mark the difference between male and females of this animal model. After statistically analyzing the results, we found significant effects of TERT overexpression in sociability, social novelty preference, anxiety, nest building, and electroseizure threshold in the males but not their female littermates. Along these differences are the male-specific increased expressions of postsynaptic proteins which are the NMDA and AMPA receptors in the prefrontal cortex. The vGluT1 presynaptic proteins, but not GAD, were upregulated in both sexes of TERT-tg mice, although it is more significantly pronounced in the male group. Here, we confirmed that the behavioral effect of TERT overexpression in mice was male-specific, suggesting that the aberration of this gene and its downstream pathways preferentially affect the functional development of the male brain, consistent with the male preponderance in ASD.
Animals ; Anxiety ; Autism Spectrum Disorder ; Brain ; Female ; Humans ; Male ; Mice ; Mice, Transgenic* ; Models, Animal ; N-Methylaspartate ; Phenotype* ; Prefrontal Cortex* ; Receptors, AMPA ; Sex Characteristics* ; Synapses ; Telomerase

Autism spectrum disorder (ASD) remains unexplained and untreated despite the high attention of research in recent years. Aside from its various characteristics is the baffling male preponderance over the female population. Using a validated animal model of ASD which is the telomerase reverse transcriptase overexpressing mice (TERT-tg), we conducted ASD-related behavioral assessments and protein expression experiments to mark the difference between male and females of this animal model. After statistically analyzing the results, we found significant effects of TERT overexpression in sociability, social novelty preference, anxiety, nest building, and electroseizure threshold in the males but not their female littermates. Along these differences are the male-specific increased expressions of postsynaptic proteins which are the NMDA and AMPA receptors in the prefrontal cortex. The vGluT1 presynaptic proteins, but not GAD, were upregulated in both sexes of TERT-tg mice, although it is more significantly pronounced in the male group. Here, we confirmed that the behavioral effect of TERT overexpression in mice was male-specific, suggesting that the aberration of this gene and its downstream pathways preferentially affect the functional development of the male brain, consistent with the male preponderance in ASD.
Animals ; Anxiety ; Autism Spectrum Disorder ; Brain ; Female ; Humans ; Male ; Mice ; Mice, Transgenic* ; Models, Animal ; N-Methylaspartate ; Phenotype* ; Prefrontal Cortex* ; Receptors, AMPA ; Sex Characteristics* ; Synapses ; Telomerase

Objective: Central nervous system involvement in coronavirus disease 2019 (COVID-19) has been increasingly reported. We performed a systematic review and meta-analysis to evaluate the incidence of radiologically demonstrated neurologic complications and detailed neuroimaging findings associated with COVID-19. Materials and Methods: A systematic literature search of MEDLINE/PubMed and EMBASE databases was performed up to September 17, 2020, and studies evaluating neuroimaging findings of COVID-19 using brain CT or MRI were included. Several cohort-based outcomes, including the proportion of patients with abnormal neuroimaging findings related to COVID-19 were evaluated. The proportion of patients showing specific neuroimaging findings was also assessed. Subgroup analyses were also conducted focusing on critically ill COVID-19 patients and results from studies that used MRI as the only imaging modality. Results: A total of 1394 COVID-19 patients who underwent neuroimaging from 17 studies were included; among them, 3.4% of the patients demonstrated COVID-19-related neuroimaging findings. Olfactory bulb abnormalities were the most commonly observed (23.1%). The predominant cerebral neuroimaging finding was white matter abnormality (17.6%), followed by acute/subacute ischemic infarction (16.0%), and encephalopathy (13.0%). Significantly more critically ill patients had COVID-19-related neuroimaging findings than other patients (9.1% vs. 1.6%; p = 0.029). The type of imaging modality used did not significantly affect the proportion of COVID-19-related neuroimaging findings. Conclusion Abnormal neuroimaging findings were occasionally observed in COVID-19 patients. Olfactory bulb abnormalities were the most commonly observed finding. Critically ill patients showed abnormal neuroimaging findings more frequently than the other patient groups. White matter abnormalities, ischemic infarctions, and encephalopathies were the common cerebral neuroimaging findings.

Benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea are commonly used preservatives in cosmetics. Recent reports suggested that these compounds may have cellular and systemic toxicity in high concentration. In addition, diazolidinyl urea and imidazolidinyl urea are known formaldehyde (FA) releasers, raising concerns for these cosmetic preservatives. In this study, we investigated the effects of benzalkonium chloride, diazolidinyl urea, and imidazolidinyl urea on ROS-dependent apoptosis of rat neural progenitor cells (NPCs) in vitro. Cells were isolated and cultured from embryonic day 14 rat cortices. Cultured cells were treated with 1–1,000 nM benzalkonium chloride, and 1–50 μM diazolidinyl urea or imidazolidinyl urea at various time points to measure the reactive oxygen species (ROS). PI staining, MTT assay, and live-cell imaging were used for cell viability measurements. Western blot was carried out for cleaved caspase-3 and cleaved caspase-8 as apoptotic protein markers. In rat NPCs, ROS production and cleaved caspase-8 expression were increased while the cell viability was decreased in high concentrations of these substances. These results suggest that several cosmetic preservatives at high concentrations can induce neural toxicity in rat brains through ROS induction and apoptosis.
Animals ; Apoptosis* ; Benzalkonium Compounds ; Blotting, Western ; Brain ; Caspase 3 ; Caspase 8 ; Cell Survival ; Cells, Cultured ; Formaldehyde ; In Vitro Techniques ; Rats* ; Reactive Oxygen Species ; Stem Cells* ; Urea