Diffusion tensor imaging of normal-appearing white matter in patients with neuromyelitis optica spectrum disorder and multiple sclerosis.

BACKGROUND AND PURPOSE: The occult changes in normal-appearing white matter (NAWM) were investigated and compared amongst patients with neuromyelitis optica spectrum disorder (NMOSD), patients with multiple sclerosis (MS) and healthy controls (HCs) by applying tract-based spatial statistics to diffusion tensor imaging (DTI) data. METHODS: Diffusion tensor imaging was performed with a 3-T scanner in 93 patients with NMOSD, 53 patients with MS and 43 HCs. Voxel-wise statistical analyses of the DTI data were performed using tract-based spatial statistics. RESULTS: Compared to HCs, patients with NMOSD had significantly lower mean global fractional anisotropy, higher mean diffusivity and radial diffusivity, and no significant differences in axial diffusivity in their NAWM. Patients with MS demonstrated significantly lower mean global fractional anisotropy and higher mean diffusivity, axial diffusivity and radial diffusivity in the NAWM than did patients with NMOSD and HCs. Compared to patients with NMOSD, patients with MS had NAWM damage that was more extensive, particularly in the inferior cerebellar peduncle, external capsule, cingulum, superior fronto-occipital fasciculus and uncinate fasciculus. CONCLUSIONS: Using DTI, widespread occult damage was demonstrated in the NAWM of patients with NMOSD. However, the NAWM was less affected in patients with NMOSD than it was in patients with MS; specifically, the axonal injuries and diffusion abnormalities in the association fibers were more severe in patients with MS than they were in patients with NMOSD.

Normal-appearing white matter demyelination in neuromyelitis optica spectrum disorder.

BACKGROUND AND PURPOSE: Increasing evidence suggests the presence of demyelination in the normal-appearing white matter (NAWM) of patients with neuromyelitis optica spectrum disorder (NMOSD). The objective was to determine the presence of subclinical demyelination in the NAWM of patients with NMOSD using myelin water imaging (MWI). METHODS: Whole brain and regions-of-interest (ROIs) analyses, including the centrum semiovale, corona radiata, genu and splenium of the corpus callosum, and optic radiation, were conducted in the NAWM of 28 NMOSD patients and 18 healthy controls (HCs) using two MWI modalities: conventional MWI and direct visualization of short transverse relaxation time component (ViSTa) MWI. RESULTS: Conventional myelin water fractions (MWFs) of the global NAWM and three ROIs (centrum semiovale, corona radiata, and genu of the corpus callosum) were slightly lower in NMOSD patients than in HCs, although not statistically significant. On the other hand, ViSTa MWF values of the global NAWM and all ROIs except the genu of the corpus callosum were significantly lower in NMOSD patients relative to HCs. In particular, the MWF in the optic radiation was significantly reduced in NMOSD patients relative to HCs in both MWI methods, even in patients who had no brain involvement. Additionally, patients with optic neuritis showed lower MWF than patients without optic neuritis and a negative correlation was identified between the MWF of the optic radiation and visual functional system score. CONCLUSIONS: This study identified the presence of widespread demyelination in the NAWM of NMOSD patients and highlighted the optic radiation as a site of marked demyelination.

Deep gray matter atrophy in neuromyelitis optica spectrum disorder and multiple sclerosis.

BACKGROUND AND PURPOSE: We investigated changes in deep gray matter (DGM) volume and its relationship to cognition and clinical factors in a large cohort of patients with neuromyelitis optica spectrum disorder (NMOSD) and compared them with results from multiple sclerosis (MS). METHODS: Brain magnetic resonance imaging (3 Tesla) and clinical data from 91 patients with NMOSD, 52 patients with MS and 44 healthy controls (HCs) were prospectively evaluated. Differences in DGM volumes were compared among groups. The relationships between DGM atrophy and clinical variables were also analysed. RESULTS: Patients with NMOSD exhibited significantly reduced thalamic volumes compared with HCs (P = 0.029), although this atrophy was less severe than that seen in patients with MS (P < 0.001). DGM atrophy was restricted to the thalamus in NMOSD, but it was broadly distributed in MS. Patients with NMOSD with cognitive impairment (CI) exhibited more severe thalamic atrophy than those with cognitive preservation (P = 0.017) and HCs (P = 0.003), whereas patients with MS with CI revealed DGM atrophy across the entire structure, with the exception of the bilateral pallidum, left hippocampus and amygdala, relative to HCs. The Expanded Disability Status Scale score was correlated with thalamic atrophy in both NMOSD and MS. Patients with NMOSD with brain lesions demonstrated more severe thalamic atrophy than did those without brain lesions and HCs (P < 0.001). CONCLUSIONS: The DGM atrophy was less severe and more selectively distributed in NMOSD than in MS. Thalamic atrophy was associated with clinical disability, including CI, in both NMOSD and MS.

Migration and Attacking Ability of Bursaphelenchus mucronatus in Pinus thunbergii Stem Cuttings.

To understand how Bursaphelenchus xylophilus kills pine trees, the differences between the effects of B. xylophilus and B. mucronatus on pine trees are usually compared. In this study, the migration and attacking ability of a non-pathogenic B. mucronatus in Pinus thunbergii were investigated. The distribution of B. mucronatus and the number of dead epithelial cells resulting from inoculation were compared with those of the pathogenic B. xylophilus. Although B. mucronatus is non-pathogenic in pines, its distribution pattern in P. thunbergii was the same as that of B. xylophilus. We therefore concluded that the non-pathogenicity of B. mucronatus could not be attributed to its migration ability. The sparse and sporadic attacking pattern of B. mucronatus was also the same as that of B. xylophilus. However, the number and area of the dead epithelial cells in pine cuttings inoculated with B. mucronatus were smaller than in those cuttings inoculated with B. xylophilus, meaning that the attacking ability of B. mucronatus is weaker than that of B. xylophilus. Therefore, we concluded that the weaker attacking ability of B. mucronatus might be the factor responsible for the non-pathogenicity.

Widespread cortical thinning in patients with neuromyelitis optica spectrum disorder.

BACKGROUND AND PURPOSE: Studies on cortical involvement and its relationship with cognitive function in patients with neuromyelitis optica spectrum disorder (NMOSD) remain scarce. The objective of this study was to compare cortical thickness on magnetic resonance imaging (MRI) between patients with NMOSD and multiple sclerosis (MS) and to investigate its relationship with clinical features and cognitive function. METHODS: This observational clinical imaging study of 91 patients with NMOSD, 52 patients with MS and 44 healthy controls was conducted from 1 December 2013 to 30 April 2015 at the institutional referral center. Three tesla MRI of the brain and neuropsychological tests were performed. Cortical thickness was measured using three-dimensional surface-based analysis. RESULTS: Both sets of patients exhibited cortical thinning throughout the entire brain cortex. Patients with MS showed a significantly greater reduction in cortical thickness over broad regions of the bilateral frontal and parieto-temporal cortices and the left precuneus compared to those with NMOSD. Memory functions in patients with MS were correlated with broad regional cortical thinning, whereas no significant associations were observed between cortical thickness and cognitive function in patients with NMOSD. CONCLUSIONS: Widespread cortical thinning was observed in patients with NMOSD and MS, but the extent of cortical thinning was greater in patients with MS. The more severe cortical atrophy may contribute to memory impairment in patients with MS but not in those with NMOSD. These results provide in vivo evidence that the severity and clinical relevance of cortical thinning differ between NMOSD and MS.

Seroprevalence of Anti-hepatitis B Virus, Anti-hepatitis A Virus, and Anti-varicella Zoster Virus Antibodies in Nursing Students from 2009 to 2013 / 병원감염관리

BACKGROUND: Nursing students may be exposed to patients with infectious diseases such as hepatitis B and hepatitis A through needle stick injuries or close contact during their clinical practice. This study surveyed the presence of antihepatitis B virus (anti-HBV), anti-hepatitis A virus (anti-HAV), and anti-varicella zoster virus antibodies in nursing students before the initiation of their clinical practice to help prevent subsequent infections. METHODS: From 2009 to 2013, the junior students of a nursing college in Jeollabuk-do were tested for antibodies against the hepatitis B, hepatitis A, and varicella zoster viruses before the initiation of their clinical practice. RESULTS: The students tested positive for anti-HBV (46.2-57.1%), anti-HAV (0-10.5%), and anti-varicella zoster antibodies (80.2-90.2%). No significant differences in the positivity rates were observed with respect to the year of their enrollment. CONCLUSION: This study was a survey of the seroprevalence of anti-HBV, anti-HAV, and anti-varicella zoster antibodies in nursing students before they started their clinical practice. The positivity rate of anti-HAV was lower than 10%. In order to prevent infection, it is necessary to test nursing students for the presence of antibodies against hepatitis B, hepatitis A, varicella, measles, mumps, and rubella, and check their vaccination history as recommended in the adult immunization schedule. Vaccination must be recommended for students who test negative for the respective antibodies.

Factors Influencing Compliance for Influenza Infection Control by Nurses / 기본간호학회지

PURPOSE: This study was conducted to investigate factors influencing influenza infection control compliance in nurses, including knowledge about, and awareness of infection control. METHODS: The study participants were 168 nurses who worked at a hospital in J Province. Data were collected by self-reported questionnaires in April 2015. Collected data were analyzed using SPSS/WIN 20.0 program. RESULTS: Mean score for knowledge about droplet precaution was 12.16 out of 16.00. Mean score for awareness about droplet precautions was 3.49 out of 4.00, and mean score for droplet precaution compliance was 3.33 out of 4.00. There was a positive correlation among knowledge, awareness and compliance (p<.001). Awareness, knowledge and experience of seasonal influenza education were the significant factors affecting the level of compliance (37.8%). CONCLUSION: Study results indicate that an educational program focusing on strategies to change nurses' awareness would be effective in improving infection control of respiratory virus and droplet precaution compliance in hospitals.

Fine-scale distribution of ectomycorrhizal fungi colonizing Tsuga diversifolia seedlings growing on rocks in a subalpine Abies veitchii forest.

Numerous species of ectomycorrhizal (ECM) fungi coexist under the forest floor. To explore the mechanisms of coexistence, we investigated the fine-scale distribution of ECM fungal species colonizing root tips in the root system of Tsuga diversifolia seedlings in a subalpine forest. ECM root tips of three seedlings growing on the flat top surface of rocks were sampled after recording their positions in the root system. After the root tips were grouped by terminal-restriction fragment length polymorphism (T-RFLP) analysis of ITS rDNA, the fungal species representing each T-RFLP group were identified using DNA sequencing. Based on the fungal species identification, the distribution of root tips colonized by each ECM fungus was mapped. Significant clustering of root tips was estimated for each fungal species by comparing actual and randomly simulated distributions. In total, the three seedlings were colonized by 40 ECM fungal species. The composition of colonizing fungal species was quite different among the seedlings. Twelve of the 15 major ECM fungal species clustered significantly within a few centimeters. Some clusters overlapped or intermingled, while others were unique. Areas with high fungal species diversity were also identified in the root system. In this report, the mechanisms underlying generation of these ECM root tip clusters in the root system are discussed.

Migrations and Multiplications of Bursaphelenchus xylophilus and B. mucronatus in Pinus thumbergii in Relation to Their Pathogenicity.

To evaluate the mechanisms of pathogenicity and non-pathogenicity of Bursaphelenchus xylophilus and B. mucronatus isolated in South Korea, we used 4-year-old P. thunbergii seedlings and 20-cm long one-year-old stem cuttings of 5-year-old Pinus thunbergii, and studied distributions and multiplications of pine wood nematodes after inoculation. The distributions of B. xylophilus in the 20-cm pine stem cuttings were not significantly different from that of B. mucronatus. Conversely, the proliferation rate of B. xylophilus on mycelial mats of Botrytis cinerea was significantly different from that of B. mucronatus. The study using 4-year-old P. thunbergii seedlings also showed that B. mucronatus can migrate to distal portions of the pine seedlings the same as B. xylophilus, but the populations of B. xylophilus remaining in the pine seedlings were relatively larger than those of B. mucronatus. Therefore, we concluded that the pathogenicity of B. xylophilus could be strongly influenced by its ability to multiply.

Morphometric Variation in Pine Wood Nematodes, Bursaphelenchus xylophilus and B. mucronatus, Isolated from Multiple Locations in South Korea.

Intraspecific variation in morphometry of pine wood nematodes Bursaphelenchus xylophilus and B. mucronatus in relation to geographical locations in South Korea was investigated using morphometric characters (body length, a, b and c ratio, stylet length, and spicule length for a male nematode and V (%) value for a female nematode). B. xylophilus was isolated from Pinus thunbergii in Jinju (1998), Ulsan (2000), Yangsan (2000), Mokpo (2001) and Jeju (2004), and from P. densiflora in Gumi (2001). B. mucronatus was isolated from P. thunbergii in Jinju (1991) and from P. densiflora in Milyang (2001). The body length of male and female B. xylophilus had the highest coefficient of variability and showed significant differences among geographical locations. The V (%) value for female B. xylophilus showed the lowest coefficient of variability, changing little with geographical area and host plant. All morphometric characters in B. mucronatus except for stylet length and female body length showed no significant differences between locations or hosts, suggesting they may not be affected by geographical area or host plant.

Outcome and Prognosis in Critically Ill Children Receiving Continuous Renal Replacement Therapy

PURPOSE: Continuous renal replacement therapy(CRRT) has been the first choice for the treatment of acute renal failure in critically ill children not only in western countries but also in Korea. However, there are very few studies that have analyzed the outcome and prognosis of this modality in Korean children. We performed this study to evaluate the factors associated with the outcome and prognosis of patients treated with CRRT. METHODS: We retrospectively reviewed the medical records of 32 children who had received CRRT at Severance hospital from 2003 to 2006. The mean age was 7.5 years(range 4 days- 16 years) and the mean body weight was 25.8 kg (range 3.2-63 kg). RESULTS: Eleven(34.4%) of the 32 patients survived. Bone marrow transplantation and malignancy were the most common causes of death and underlying disease leading to the need for CRRT. Mean patient weight, age, duration of CRRT, number of organ failures, urine output, estimated glomerular filtration rate(eGFR), C-reactive protein, and blood urea level did not differ significantly between survivors and nonsurvivors. (1) Pediatric risk of mortality(PRISM) III score at CRRT initiation(9.8+/-5.3 vs. 26.7+/-7.6, P<0.0001), (2) maximum pressor number (2.1+/-1.2 vs. 3.0+/-1.0, P=0.038), and (3) the degree of fluid overload(5.2+/-6.0 vs. 15.0+/-8.9, P=0.002) were significantly lower in survivors than in nonsurvivors. Multivariate analysis revealed that fluid overload was the only independent factor reducing survival rate. CONCLUSION: CRRT was successfully applied to the treatment of acute renal failure in a wide range of critically ill children. To improve survival, we suggest the early initiation of CRRT to prevent the systemic worsening and progression of fluid overload in critically ill children with acute renal failure.

The Prognosis of Focal Segmental Glomerulosclerosis Patients with Methylprednisolone Pulse Therapy Alone

PURPOSE: Since the first report by Mendoza in 1990, there have been several studies reporting that long-term intravenous methylprednisolone(MP) pulse therapy combined with cyclosporin A(CsA) or cyclophosphamide might be beneficial for the treatment of steroid resistant focal segmental glomerulosclerosis(FSGS). We investigated the therapeutic effect of long-term MP pulse therapy without CsA or cyclophosphamide on steroid resistant FSGS. METHODS: The medical records of the 10 steroid resistant FSGS patients who were treated with MP pulse therapy by the Mendoza protocol without CsA or cyclophosphamide in our hospital were retrospectively reviewed. RESULTS: The median age at onset was 2.6 years(range 1.1-10.6 years) and the median age at the initiation of therapy was 5.7 years(range 1.8-20 years). The median duration of follow-up was 35 months(range 4-132 months). At the end of therapy, 5 patients achieved complete remission(50%) and 2 partial remission(20%), one of whom relapsed after the therapy. Three patients did not respond to the therapy, two of whom progressed to end-stage renal failure during the therapy eventually requiring kidney transplantation. CONCLUSION: Intravenous long-term MP pulse therapy without CsA or cyclophosphamide by the Mendoza protocol may be effective in a subset of patients with steroid-resistant FSGS.

The Clinical Usefulness of Cystatin C in Evaluating Renal Function in Children with Various Renal Diseases

PURPOSE: GFR(glomerular filtration rate) is a fundamental parameter in detecting renal impairment and predicts the progression of renal disease. Because serum creatinine has several disadvantages, serum cystatin C has been recently proposed as a new endogenous marker for GFR. We compared serum cystatin C with creatinine and creatinine clearance to investigate the clinical usefulness of cystatin C. METHODS: We retrospectively analyzed 46 patients(60 case numbers) who had various renal diseases and classified them into 3 groups according to creatinine clearance(Group 1 : CrCl 60 mL/min/1.73 m2). We measured serum creatinine, cystatin C and creatinine clearance and also analyzed the correlations among them. RESULTS: Serum cystatin C and creatinine showed a similar correlation to creatinine clearance (r=0.685, r=0.640, respectively) and showed similar diagnostic accuracy in detecting decreased GFR(AUC, cystatin C 0.829 vs. creatinine 0.826, P=0.848). Serum cystatin C showed a greater sensitivity for detecting a decreased GFR than creatinine in Group 2 and 3(Group 1 : 100% vs. 100%, Group 2 : 70% vs. 35%, Group 3 : 46% vs. 15%). CONCLUSIONS: Serum cystatin C could be a useful endogenous marker for GFR and would be superior to serum creatinine in early detection of renal impairment in pediatric patients with renal diseases.

A Case of Renovascular Hypertension Due to Renal Artey Stenosis Related to Moyamoya Disease

Moyamoya disease is a progressive cerebrovascular disorder with stenosis or occlusion of the bilateral internal carotid arteries with abnormal vascular networks at the base of the brain. Previous reports have shown that there are extracranial vascular involvements in Moyamoya disease, especially in the renal artery. We report a 7-year-old patient with Moyamoya disease associated with renovascular hypertension, who presented in infancy with seizures and hemiparesis. Renal angiography showed multiple stenoses of the right renal artery. Although renal artery stenosis in Moyamoya disease has been effectively treated with balloon angioplasty, stent implantation, or surgery, balloon angioplasty could not be done in this patient due to multiple stenoses. His blood pressure was successfully controlled with medical treatment, and remained normotensive during the follow up period of 6 months.

Immunophenotyping and DNA analysis of lymphoid leukemic cells by FACScan system / 대한임상병리학회지

No abstract available.

Liver disease and anti-HCV antibody / 대한임상병리학회지

No abstract available.