• Investigative Magnetic Resonance Imaging
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• v.17 no.1
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• pp.50-54
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• 2013

Nocardiosis is an uncommon Gram-positive bacterial infection caused by aerobic actinomycetes in the genus Nocardia. Nocardia spp. have the ability to cause localized or systemic suppurative disease in humans and animals. Nocardiosis is typically regarded as an opportunistic infection, but approximately one-third of infected patients are immunocompetent. We report a rare case of pulmonary nocardiosis and a brain abscess caused by Nocardia asteroides in an elderly woman with a history of Crohn's disease. Radiographic imaging revealed a contrast-enhancing lesion with perilesional parenchymal edema that was preoperatively thought to be a neoplasm. The patient experienced aggressive disease progression simulating a metastatic brain tumor. Early diagnosis of norcadiosis, the absence of underlying disease, and the administration of appropriate antibiotics has a positive impact on prognosis. Familiarity with the magnetic resonance and computed tomography findings associated with CNS nocardiosis, such as those presented here, is essential for making an early diagnosis.

• Parasites, Hosts and Diseases
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• v.58 no.4
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• pp.461-466
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• 2020

Toxoplasma gondii is an obligate intracellular protozoan parasite that can invade various organs in the host body, including the central nervous system. Chronic intracranial T. gondii is known to be associated with neuroprotection against neurodegenerative diseases through interaction with host brain cells in various ways. The present study investigated the neuroprotective effects of chronic T. gondii infection in mice with cerebral ischemia experimentally produced by middle cerebral artery occlusion (MCAO) surgery. The neurobehavioral effects of cerebral ischemia were assessed by measurement of Garcia score and Rotarod behavior tests. The volume of brain ischemia was measured by triphenyltetrazolium chloride staining. The expression levels of related genes and proteins were determined. After cerebral ischemia, corrected infarction volume was significantly reduced in T. gondii infected mice, and their neurobehavioral function was significantly better than that of the uninfection control group. Chronic T. gondii infection induced the expression of hypoxia-inducible factor 1-alpha (HIF-1α) in the brain before MCAO. T. gondii infection also increased the expression of vascular endothelial growth factor after the cerebral ischemia. It is suggested that chronic intracerebral infection of T. gondii may be a potential preconditioning strategy to reduce neural deficits associated with cerebral ischemia and induce brain ischemic tolerance through the regulation of HIF-1α expression.

• Journal of Korean Neurosurgical Society
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• v.58 no.1
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• pp.14-21
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• 2015

Objective : To study the effect of early intervention and rehabilitation in the expression of aquaporin-4 and ultrastructure changes on cerebral palsy pups model induced by intrauterine infection. Methods : 20 pregnant Wistar rats were consecutively injected with lipopolysaccharide intraperitoneally. 60 Pups born from lipopolysaccharide group were randomly divided into intervention group (n=30) and non-intervention group (n=30); intervention group further divided into early intervention and rehabilitation group (n=10), acupuncture group (n=10) and consolidate group (n=10). Another 5 pregnant rats were injected with normal saline intraperitoneally; 30 pups born from the normal saline group were taken as control group. The intervention group received early intervention, rehabilitation and acupuncture treatment. The motor functions of all pups were assessed via suspension test and modified BBB locomotor score. Aquaporin-4 expression in brain tissue was studied through immunohistochemical and western-blot analysis. Ultrastructure changes in damaged brain and control group were studied electron-microscopically. Results : The scores of suspension test and modified BBB locomotor test were significantly higher in the control group than the intervention and non intervention group (p<0.01); higher in the intervention group than the non-intervention group (p<0.01). The expression of Aquaporin-4 was lower in intervention and non intervention group than in the control group (p<0.01); also lower in non-intervention group than the intervention group (p<0.01). Marked changes were observed in ultrastructure of cortex and hippocampus CAI in brain damaged group. Conclusion : Early intervention and rehabilitation training can improve the motor function in offspring with brain injury and reduce the expression of aquaporin-4 in damaged brain.

• Pediatric Infection and Vaccine
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• v.30 no.3
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• pp.159-164
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• 2023

A brain abscess is a potentially life-threatening infection of the brain that can be challenging to diagnose, especially in children. In this report, we describe a case of a central nervous system infection caused by rare pathogens in an immunocompetent child. A 10-year-old female presented with a severe headache lasting 10 days, along with flashing lights, nausea, and vomiting. The patient was diagnosed with secundum atrial septal defect 7 years ago and underwent dental work for cavities one month prior to admission. Brain magnetic resonance imaging (MRI) showed a 4.2 cm sized brain abscess in the right parietal lobe, causing left inferior quadrantanopia. A craniotomy and abscess aspiration surgery were performed, and cultures from the aspirated pus and tissue revealed Aggregatibacter aphrophilus. Additionally, Actinomyces georgiae was identified through 16S rRNA sequencing. After 8 weeks of antimicrobial therapy with ampicillin-sulbactam, the patient was discharged without any complications. A follow-up brain MRI showed complete resolution of the abscess and edema.

• Journal of Veterinary Science
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• v.22 no.2
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• pp.20.1-20.13
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• 2021

Background: Pseudorabies virus (PRV) infection leads to high mortality in swine. Despite extensive efforts, effective treatments against PRV infection are limited. Furthermore, the inflammatory response induced by PRV strain GXLB-2013 is unclear. Objectives: Our study aimed to investigate the inflammatory response induced by PRV strain GXLB-2013, establish an inflammation model to elucidate the pathogenesis of PRV infection further, and develop effective drugs against PRV infection. Methods: Kunming mice were infected intramuscularly with medium, LPS, and different doses of PRV-GXLB-2013. Viral spread and histopathological damage to brain, spleen, and lung were determined at 7 days post-infection (dpi). Immune organ indices, levels of reactive oxygen species (ROS), nitric oxide (NO), and inflammatory cytokines, as well as levels of activity of COX-2 and iNOS were determined at 4, 7, and 14 dpi. Results: At 10⁵-10⁶ TCID₅₀ PRV produced obviously neurological symptoms and 100% mortality in mice. Viral antigens were detectable in kidney, heart, lung, liver, spleen, and brain. In addition, inflammatory injuries were apparent in brain, spleen, and lung of PRV-infected mice. Moreover, PRV induced increases in immune organ indices, ROS and NO levels, activity of COX-2 and iNOS, and the content of key pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ and MCP-1. Among the tested doses, 10² TCID₅₀ of PRV produced a significant inflammatory mediator increase. Conclusions: An inflammatory model induced by PRV infection was established in mice, and 10² TCID50 PRV was considered as the best concentration for the establishment of the model.

• Journal of Korean Neurosurgical Society
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• v.60 no.1
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• pp.118-124
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• 2017

Brain abscess commonly occurs secondary to an adjacent infection (mostly in the middle ear or paranasal sinuses) or due to hematogenous spread from a distant infection or trauma. Pulmonary arteriovenous fistulas (AVFs) are abnormal direct communications between the pulmonary artery and vein. We present two cases of brain abscess associated with asymptomatic pulmonary AVF. A 65-year-old woman was admitted with a headache and cognitive impairment that aggravated 10 days prior. An magnetic resonance (MR) imaging revealed a brain abscess with severe edema in the right frontal lobe. We performed a craniotomy and abscess removal. Bacteriological culture proved negative. Her chest computed tomography (CT) showed multiple AVFs. Therapeutic embolization of multiple pulmonary AVFs was performed and antibiotics were administered for 8 weeks. A 45-year-old woman presented with a 7-day history of progressive left hemiparesis. She had no remarkable past medical history or family history. On admission, blood examination showed a white blood cell count of 6290 cells/uL and a high sensitive C-reactive protein of 2.62 mg/L. CT and MR imaging with MR spectroscopy revealed an enhancing lesion involving the right motor and sensory cortex with marked perilesional edema that suggested a brain abscess. A chest CT revealed a pulmonary AVF in the right upper lung. The pulmonary AVF was obliterated with embolization. There needs to consider pulmonary AVF as an etiology of cerebral abscess when routine investigations fail to detect a source.

• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1167-1175
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• 2013

Paratuberculosis (PTB) or Johne's disease is one of the most serious chronic debilitating diseases of ruminants worldwide that is caused by Mycobacterium avium subsp. paratuberculosis (MAP). MAP is a slow-growing bacterium that has very long latent periods, resulting in difficulties in diagnosing and controlling the disease, especially regarding the diagnosis of fecal shedders of MAP without any clinical signs. Based on this situation, attempts were made to identify biomarkers that show early responses to MAP infection in a macrophage cell line, RAW 264.7. In response to the infection with the bacterium, a lot of genes were turned on and/or off in the cells. Of the altered genes, three different categories were identified based on the time-dependent gene expression patterns. Those genes were considered as possible candidates for biomarkers of MAP infection after confirmation by quantitative RT-PCR analysis. To the best of our knowledge, this is the first attempt at discovering the host transcriptomic biomarkers of PTB, although further investigation will be required to determine whether these biomarker candidates are associated within the natural host.

• Journal of Korean Neurosurgical Society
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• v.30 no.12
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• pp.1430-1434
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• 2001

The authors present a case of brain abscess in a patient with primary mucociliary transport failure. Primary mucociliary transport failure is unfamiliar term to neurosurgeon. It encompasses three hereditary disorders, that is, primary ciliary dyskinesia, cystic fibrosis and Young's syndrome. Clinical manifestations in these disorders appear to overlap each other, e.g., male infertility and chronic sinopulmonary infections. These are characterized by ciliary dysfunction or abnormality of mucus secretion therefore recurrent infection occurs in organs containing the mucociliary transport system. Major causes of non-traumatic brain abscess are sinusitis and pulmonary infection. So the possibility of brain abscess is much higher if mucociliary transport failure exists. Especially, young patients who have brain abscess coexisting with chronic sinopulmonary infection should be considered primary mucociliary transport failure.

• Journal of Korean Neurosurgical Society
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• v.59 no.1
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• pp.52-57
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• 2016

Objective : Many surgeons advocate for watertight dural reconstruction after posterior fossa surgery given the significant risk of cerebrospinal fluid (CSF) leak. Little evidence exists for posterior fossa dural reconstruction utilizing monolayer collagen matrix onlay graft in a non-watertight fashion. Our objective was to report the results of using collagen matrix in a non-watertight fashion for posterior fossa dural reconstruction. Methods : We conducted a retrospective review of operations performed by the senior author from 2004-2011 identified collagen matrix (DuraGen) use in 84 posterior fossa operations. Wound complications such as CSF leak, infection, pseudomeningocele, and aseptic meningitis were noted. Fisher's exact test was performed to assess risk factor association with specific complications. Results : Incisional CSF leak rate was 8.3% and non-incisional CSF leak rate was 3.6%. Incidence of aseptic meningitis was 7.1% and all cases resolved with steroids alone. Incidence of palpable and symptomatic pseudomeningocele in follow-up was 10.7% and 3.6% respectively. Postoperative infection rate was 4.8%. Previous surgery was associated with pseudomeningocele development (p<0.05). Conclusion : When primary dural closure after posterior fossa surgery is undesirable or not feasible, non-watertight dural reconstruction with collagen matrix resulted in incisional CSF leak in 8.3%. Incidence of pseudomeningocele, aseptic meningitis, and wound infection were within acceptable range. Data from this study may be used to compare alternative methods of dural reconstruction in posterior fossa surgery.

• Journal of Aquaculture
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• v.19 no.3
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• pp.197-204
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• 2006

The pathogenicity and infection route of the Scuticociliate, Philasterdies dicentrarchi, were investigated with the 3 and 5 cm-group of juvenile flounders, Paralichthys olivaceus. The infection rates of 3 cm-group were 40% four days post infection (D.P.I.) and increased to be 90.1% 24 D.P.I., whereas those of 5 cm-group were 20% 8 D.P.I., 42% 16 D.P.I., and 81% 24 D.P.I. The results showed there were several infection routes to internal organs Olive flounder. The first route was started with the infection at the soft part of caudal fin and later reached at fin ray and muscle tissue; the second one was started from lips and mouth tissue of upper jaw and later the pathogen could be observed at either muscle tissue or eyeball and brain; the third one was begun at caudal fin and later the pathogen reached at brain tissu'e through spiral cord; the fourth one was started with the infections at abdominal cavity and anus. P. dicentrarchi infected to brain tissue was first observed 14 D.P.I in 3 cm-group and 20 D.P.I. in 5 cm-group of the juvenile flounder. This indicated that the brain infection of P. dicentrarchi might occur faster in small-sized flounder than large-sized one.