Exosome-mediated secretion of miR-127-3p regulated by RAB27A accelerates metastasis in renal cell carcinoma.

BACKGROUND: The exosome-mediated extracellular secretion of miRNAs occurs in many cancers, and RAB27A is a potent regulator of exosome secretion. For metastatic renal cell carcinoma (RCC), this study examines the mechanisms of cancer metastasis via the RAB27A-regulated secretion of specific miRNAs. METHODS: RAB27A knockdown (KD) and overexpressing (OE) RCC cells were used to examine cell migration and adhesion. The particle counts and sizes of exosomes in RAB27A OE cells were analyzed using Exoview, and those of intraluminal vesicles (ILV) and multivesicular bodies (MVB) were measured using an electron microscope. Analysis of RNA sequences, protein-protein interaction networks, and the competing endogenous RNA (ceRNA) network were used to identify representative downregulated miRNAs that are likely to undergo cargo-sorting into exosomes and subsequent secretion. A molecular beacon of miR-137-3p, one of the most representatively downregulated genes with a fold change of 339, was produced, and its secretion was analyzed using Exoview. RAB27A OE and control cells were incubated in an exosome-containing media to determine the uptake of tumor suppressor miRNAs that affect cancer cell metastasis. RESULTS: Migration and cell adhesion were higher in RAB27A OE cells than in RAB27A KD cells. Electron microscopy revealed that the numbers of multivesicular bodies and intraluminal vesicles per cell were higher in RAB27A OE cells than in control cells, suggesting their secretion. The finding revealed that miR-127-3p was sorted into exosomes and disposed of extracellularly. Protein-protein interaction analysis revealed MYCN to be the most significant hub for RAB27A-OE RCC cells. ceRNA network analysis revealed that MAPK4 interacted strongly with miR-127-3p. CONCLUSION: The disposal of miR-127-3p through exosome secretion in RAB27A overexpressing cells may not inhibit the MAPK pathway to gain metastatic potential by activating MYCN. The exosomes containing miRNAs are valuable therapeutic targets for cancer treatment.

Comparative real-world outcomes between ustekinumab, infliximab, and adalimumab in bio-naïve and bio-experienced Crohn's disease patients: a retrospective multicenter study.

BACKGROUND: Numerous studies have compared the efficacy of ustekinumab (UST) and anti-TNF agents [infliximab (IFX) or adalimumab(ADA)] in moderate to severe Crohn's disease (CD) patients. This study aims to compare the efficacy of UST, IFX, and ADA while differentiating between bio-naïve and bio-experienced patients, which is an underexplored aspect, particularly in Asia. METHODS: We conducted a retrospective multi-center study from 2012 to 2023, categorizing patients into bio-naïve and bio-experienced groups. We evaluated clinical remission rates after induction therapy and clinical outcomes, including CD-related hospitalization, intestinal resection, and drug discontinuation during maintenance therapy. RESULTS: Among the 214 bio-naïve CD patients, 60 received UST, 108 received IFX, and 46 received ADA. After 1:1 propensity score matching between UST and anti-TNF agents groups, 59 patients were analyzed in each group (45 in the IFX group and 14 in the ADA group). We found no significant differences in clinical remission rates (P = 0.071), CD-related hospitalization (P = 0.800), intestinal resection (P = 0.390), or drug discontinuation (P = 0.052) between the UST, IFX, and ADA groups in bio-naïve CD patients. In bio-experienced CD patients, with 35 in the UST group and 13 in the anti-TNF agents group, the UST group showed a lower risk of drug discontinuation (P = 0.004) than the anti-TNF agents group. CONCLUSIONS: This study suggests that UST, IFX, and ADA are equally effective in bio-naïve CD patients, while in bio-experienced patients, mostly with previous exposure to anti-TNF agents, UST may offer superior drug durability.

Does an untreated peri-implant dehiscence defect affect the progression of peri-implantitis?: A preclinical in vivo experimental study.

OBJECTIVE: To investigate the early impact of plaque accumulation in a buccal dehiscence defect on peri-implant marginal bone resorption. MATERIALS AND METHODS: In six male Mongrel dogs, four dental implants were placed in the posterior maxilla on both sides (two implants per side). Based on the group allocation, each implant was randomly assigned to one of the following four groups to decide whether buccal dehiscence defect was prepared and whether silk ligation was applied at 8 weeks post-implant placement for peri-implantitis induction: UC (no defect without ligation); UD (defect without ligation); LC (no defect with ligation); and LD (defect with ligation) groups. Eight weeks after disease induction, the outcomes from radiographic and histologic analyses were statistically analyzed (p < .05). RESULTS: Based on radiographs, the exposed area of implant threads was smallest in group UC (p < .0083). Based on histology, both the distances from the implant platform to the first bone-to-implant contact point and to the bone crest were significantly longer in the LD group (p < .0083). In the UD group, some spontaneous bone fill occurred from the base of the defect at 8 weeks after implant placement. The apical extension of inflammatory cell infiltrate was significantly more prominent in the LD and LC groups compared to the UC group (p < .0083). CONCLUSION: Plaque accumulated on the exposed implant surface had a negative impact on maintaining the peri-implant marginal bone level, especially when there was a dehiscence defect around the implant.

A case of exacerbated encephalopathy with stroke-like episodes and lactic acidosis triggered by metformin in a patient with MELAS.

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a maternally inherited multisystemic disorder caused by mutations in mitochondrial DNA that result in cellular energy deficiency. MELAS affects the most metabolically active organs, including the brain, skeletal muscles, cochlea, retina, heart, kidneys, and pancreas. As a result, about 85% of carriers of m.3243A > G, the most common mutation in MELAS, develop diabetes by the age of 70. Although metformin is the most widely prescribed drug for diabetes, its usefulness in mitochondrial dysfunction remains controversial. Here, we present the case of a 32-year-old Korean patient diagnosed with MELAS who presented with exacerbated stroke-like episodes and lactic acidosis triggered by metformin.

Incidence of invasive fungal diseases in inflammatory bowel disease patients: A nationwide study in South Korea.

BACKGROUND: Limited reports exist regarding invasive fungal diseases (IFDs) in inflammatory bowel disease (IBD) patients. OBJECTIVES: This study aims to investigate the incidence and risk factors of IFDs, specifically invasive candidiasis, aspergillosis and pneumocystosis, in IBD patients in South Korea using nationwide data. PATIENTS/METHODS: A population-based retrospective cohort of 42,913 IBD patients between January 2010 and December 2018 was evaluated using the Health Insurance Review and Assessment database. The primary outcome was the incidence of IFDs, including invasive candidiasis, aspergillosis and pneumocystosis, while the secondary outcome involved analysing the risk factors associated with each specific infection. RESULTS: The study included a total of 42,913 IBD patients, with 29,909 (69.7%) diagnosed with ulcerative colitis (UC) and 13,004 (30.3%) diagnosed with Crohn's disease (CD). IFDs occurred in 166 IBD patients (0.4%), with 93 cases in UC patients and 73 cases in CD patients. The incidence rates of invasive candidiasis, aspergillosis and pneumocystosis in IBD patients were 0.71 per 1000 person-years (PYs), 0.15 per 1000 PYs and 0.12 per 1000 PYs, respectively. The cumulative incidence of invasive candidiasis (adjusted p-value <.001) and Pneumocystosis (adjusted p-value = .012) was found to be higher in CD patients than in UC patients. Each IFD had different risk factors, including IBD subtypes, age at diagnosis, anti-tumour necrotic factor agents or the Charlson comorbidity index. CONCLUSION: Based on nationwide data in South Korea, this study shows that IFDs occur consistently in patients with IBD, albeit with a low frequency.

Feasibility of Simultaneous Anodal Transcranial Direct Current Stimulation During Gait Training in Chronic Stroke Patients: A Randomized Double-Blind Pilot Clinical Trial.

BACKGROUND: Transcranial direct current stimulation (tDCS) is a therapeutic tool for improving post-stroke gait disturbances, with ongoing research focusing on specific protocols for its application. We evaluated the feasibility of a rehabilitation protocol that combines tDCS with conventional gait training. METHODS: This was a randomized, double-blind, single-center pilot clinical trial. Patients with unilateral hemiplegia due to ischemic stroke were randomly assigned to either the tDCS with gait training group or the sham stimulation group. The anodal tDCS electrode was placed on the tibialis anterior area of the precentral gyrus while gait training proceeded. Interventions were administered 3 times weekly for 4 weeks. Outcome assessments, using the 10-meter walk test, Timed Up and Go test, Berg Balance Scale, Functional Ambulatory Scale, Modified Barthel Index, and European Quality of Life 5 Dimensions 3 Level Version, were conducted before and after the intervention and again at the 8-week mark following its completion. Repeated-measures analysis of variance (ANOVA) was used for comparisons between and within groups. RESULTS: Twenty-six patients were assessed for eligibility, and 20 were enrolled and randomized. No significant differences were observed between the tDCS with gait training group and the sham stimulation group in gait speed after the intervention. However, the tDCS with gait training group showed significant improvement in balance performance in both within-group and between-group comparisons. In the subgroup analysis of patients with elicited motor-evoked potentials, comfortable pace gait speed improved in the tDCS with gait training group. No serious adverse events occurred throughout the study. CONCLUSIONS: Simultaneous anodal tDCS during gait training is a feasible rehabilitation protocol for chronic stroke patients with gait disturbances. CLINICAL TRIAL REGISTRATION: URL: https://cris.nih.go.kr; Registration number: KCT0007601; Date of registration: 11 July 2022.

Can balloon-assisted enteroscopy predict disease outcomes in patients with small-bowel Crohn's disease?

There are limited studies on the endoscopic assessment of disease activity using balloon-assisted enteroscopy (BAE) and its predictive role for long-term outcomes of patients with small bowel Crohn's disease (CD). We sought to investigate the value of BAE as a predictor of long-term outcomes in patients with small-bowel CD. A total of 111 patients with small-bowel CD whose endoscopic disease activity was assessed using BAE based on the small-bowel simple endoscopic score for Crohn's disease (small-bowel SES-CD) at Samsung Medical Center were retrospectively selected from January 2014 to August 2020. The outcome was an evaluation of the risk of surgery according to a small-bowel SES-CD of 0-6 vs. ≥ 7 and endoscopic findings (presence of any ulcer and degree of stricture) using the Cox proportional hazards model. The risk of surgery was significantly increased in patients with a small-bowel SES-CD of ≥ 7 compared to a small-bowel SES-CD of 0-6 [hazard ratio (HR) 6.31; 95% confidence interval (CI) 1.48-26.91; p = 0.013]. In addition, the risk of surgery was significantly increased in patients with stenosis with "cannot be passed" compared to the cases without stenosis (HR 12.34; 95% CI 1.66-91.92; p = 0.014), whereas there was no significance in any ulcer. The present study demonstrated the role of BAE in the endoscopic assessment of disease activity and its predictive value for the risk of surgery in small-bowel CD patients. Further optimization of BAE utilization for the assessment of disease activity is warranted in clinical practice.

The optimal surgery timing after stenting in colorectal cancer patients with malignant obstruction: additionally compared with emergency surgery.

BACKGROUND: This study aimed to determine short-term and long-term outcomes according to time intervals after stenting and compared them with those of emergency surgery (ES) in colorectal cancer (CRC) with malignant obstruction. METHODS: CRC with malignant obstructions was reviewed retrospectively between January 2008 and July 2018. Of a total of 539 patients who visited the emergency room and underwent ES, 133 were enrolled in the ES group. Of a total of 567 patients who initially received stenting and subsequently underwent elective surgery, 220 were enrolled in the SEMS group. The interval between SEMS placement and elective surgery was classified as < 11 days, 11-17 days, and > 17 days. RESULTS: For those who received SEMS (n = 220), those with a time interval of 11-17 days (n = 97) had fewer hospital days than those with a time interval of < 11 days (n = 68) (8 days vs. 15 days) and less stoma formation than those with a time interval of > 17 days (n = 55) (1.0% vs. 14.6%). Multivariable analysis revealed a decreased risk of death for the group with a time interval of 11-17 days (20.6%) compared to the ES group (31.6%) (hazard ratio: 0.48; 95% confidence interval: 0.24-0.97). Disease-free survival was comparable between the SEMS and ES groups regardless of the time interval (log-rank p = 0.52). CONCLUSIONS: The time interval of 11-17 days after stenting to elective surgery appeared to be associated with the most favorable outcomes.

Blood Concentrations of Lead, Cadmium, and Mercury Are Associated With Alcohol-Related Liver Disease.

BACKGROUND: An association between environmental pollutants and alcohol-related liver disease (ALD) has not been determined until now. The objectives of this study were to examine the association of the pollutants with ALD, and whether the pollutants together increased the risk of ALD. METHODS: Data were extracted from the Korea National Health and Nutrition Examination Survey (2010-2013 and 2016-2017; n = 11,993). Blood levels of lead, cadmium, and mercury were measured. ALD was defined by a combination of excessive alcohol consumption and ALD/non-alcoholic fatty liver disease index > 0. The aspartate aminotransferase-to-platelet ratio index and fibrosis (FIB)-4 score were used to evaluate ALD FIB. RESULTS: The odds ratios (ORs) of ALD for the highest versus the lowest quartiles of exposure were for lead, 7.39 (95% confidence interval [CI], 5.51-9.91); cadmium, 1.68 (95% CI, 1.32-2.14); and mercury, 5.03 (95% CI, 3.88-6.53). Adjusting for age, gender, smoking, occupation, education, and personal income attenuated the associations but indicated significant positive trends (all Ptrend < 0.001). A positive additive interaction between cadmium and lead was observed. The relative excess OR due to the interaction was 0.96 (95% CI, 0.41-1.51); synergy index = 2.92 (95% CI, 0.97-8.80). Among 951 subjects with ALD, advanced FIB was associated with lead and cadmium (OR, 3.46, 95% CI, 1.84-6.53; OR, 8.50, 95% CI, 2.54-28.42, respectively), but not with mercury. The effect estimates for lead and cadmium remained significant even after adjustment for daily alcohol intake. CONCLUSION: Blood levels of lead, cadmium, and mercury were significantly associated not only with the risk of ALD but also with ALD FIB. Cadmium and lead have synergistic effects that increase the risk of ALD.

Genotype-phenotype analysis of MT-ATP6-associated Leigh syndrome.

OBJECTIVES: Mitochondrial DNA (mtDNA)-associated Leigh syndrome (LS) is characterized by maternal inheritance, and the heteroplasmic mutant load of mtDNA pathogenic variants is known to affect clinical phenotypes. Among mtDNA pathogenic variants, variants of the MT-ATP6 gene account for most of reported cases. In this report, we aimed to describe the clinical and genetic findings of MT-ATP6-associated LS patients diagnosed at a single tertiary institution in Korea. METHODS: Thirteen patients with genetically confirmed MT-ATP6-associated LS were selected. We reviewed each patient's clinical findings, including general characteristics, biochemical parameters, brain MR images, muscle biopsy results, and heteroplasmic mutant load over a long-term follow-up period. RESULTS: MT-ATP6-associated LS was of predominantly early onset (age <2 years), although we identified 2 late-onset (>60 months) LS patients. The heteroplasmic mutant load estimated by next-generation sequencing was 96%-100% in all nucleotide change groups. Compared with other forms of MT-ATP6-associated LS, the m.8993T>G point mutation elicited a significantly higher rate of symptom onset before 2 years of age. Brain MRI showed bilateral basal ganglia involvement in all patients, followed by cerebral atrophy, brainstem and thalamus involvement, and cerebellar atrophy. After follow-up (median 7.2 years, range 1.4 to 11.5 years), LS with m.8993T>G point mutations had a slightly more severe clinical progression compared with other forms of MT-ATP6-associated LS. CONCLUSIONS: MT-ATP6-associated LS patients presented with a broad spectrum of clinical diagnoses and had a very high heteroplasmic mutant load. This study provides valuable data on MT-ATP6-associated LS that will inform subsequent studies on LS.

Efficacy of entecavir versus tenofovir in preventing hepatocellular carcinoma in patients with chronic hepatitis B with maintained virologic response.

BACKGROUND & AIMS: Several studies suggested that efficacy of tenofovir in reducing the risk of the development of hepatocellular carcinoma (HCC) might be better than that of entecavir. It remains unknown whether a change in therapy can further reduce the risk of HCC in patients receiving entecavir therapy and achieved goal of antiviral therapy, a maintained undetectable hepatitis B virus (HBV) DNA level in the serum. METHODS: A total of 1336 treatment-naïve chronic HBV mono-infected adult patients, who started entecavir or tenofovir treatment and achieved a maintained virologic response during follow-up were analysed. RESULTS: During a median 4.4 years of follow-up (range, 1.0-7.4 years) after achieving virologic response, 99 patients developed HCC. The 5-year cumulative HCC incidence rate was 7.3% and 6.3% for the entecavir and tenofovir groups, respectively, with similar risk of HCC between the two groups (adjusted HR, 0.82; 95% CI, 0.52-1.29; p = 0.3). The risk of HCC was similar in the propensity score-matched cohort (HR, 1.02; 95% CI, 0.68-1.52; p = 0.94) and inverse probability treatment weighting analysis (HR, 1.11; 95% CI, 0.74-1.66; p = 0.62). In the subgroup analysis, HCC risk was similar between the two drugs in both patients with and without cirrhosis. DISCUSSION: In patients showing maintained virologic response, no difference in the risk of HCC between entecavir and tenofovir was observed. This indicates entecavir might be as effective as tenofovir in the prevention of HCC among those patients and suggest that a change in therapy in anticipation of further reducing the risk of HCC might not be necessary for patients receiving entecavir and showing virologic response.

Long-Term Safety of Delayed Surgery After Upfront Endoscopic Resection for Early Gastric Cancer: A Propensity Matched Study.

BACKGROUND: When non-curative resection is confirmed after endoscopic resection (ER) of early gastric cancer (EGC), delayed surgery is recommended because it provides favorable survival outcomes. Long-term outcome after surgery of EGC with or without previous ER has not been evaluated. OBJECTIVE: The aim of this study was to compare the long-term oncologic safety between primary surgery and delayed surgery after ER. METHODS: Patients who had undergone curative surgery (R0) for EGC were included and were divided into primary and delayed surgery groups. Primary surgery was defined as gastrectomy without ER for EGC, whereas delayed surgery was defined as additional curative gastrectomy due to non-curative resection after ER; an average delay of 21.5 days (range 1-195) was observed. Propensity score matching was performed. The primary outcome was overall survival (OS) and the secondary outcomes were cancer-specific survival (CSS) and disease-free survival (DFS). RESULTS: After propensity score matching, 1439 patients were included, of whom 1042 (72.4%) were in the primary surgery group and 397 (27.6%) were in the delayed surgery group. The OS (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.59-1.27; p = 0.459), CSS (HR 0.47, 95% CI 0.15-1.47; p = 0.196), and DFS (HR 0.54, 95% CI 0.15-1.90; p = 0.334) were not different. CONCLUSIONS: The long-term outcomes of delayed surgery after non-curative ER for EGC were non-inferior to primary surgery. Therefore, an attempt for ER of EGC that satisfies the absolute and expanded indication seems justified for preventing gastrectomy. In case of non-curative resection after ER, additional delayed surgery should be performed.

Generation of homogeneous midbrain organoids with in vivo-like cellular composition facilitates neurotoxin-based Parkinson's disease modeling.

Recent studies have demonstrated the generation of midbrain-like organoids (MOs) from human pluripotent stem cells. However, the low efficiency of MO generation and the relatively immature and heterogeneous structures of the MOs hinder the translation of these organoids from the bench to the clinic. Here we describe the robust generation of MOs with homogeneous distribution of midbrain dopaminergic (mDA) neurons. Our MOs contain not only mDA neurons but also other neuronal subtypes as well as functional glial cells, including astrocytes and oligodendrocytes. Furthermore, our MOs exhibit mDA neuron-specific cell death upon treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, indicating that MOs could be a proper human model system for studying the in vivo pathology of Parkinson's disease (PD). Our optimized conditions for producing homogeneous and mature MOs might provide an advanced patient-specific platform for in vitro disease modeling as well as for drug screening for PD.

Central precocious puberty may be a manifestation of endocrine dysfunction in pediatric patients with mitochondrial disease.

We retrospectively reviewed the data of 140 female pediatric patients with rare mitochondrial diseases (MDs) confirmed using muscle biopsy. We evaluated patients who were diagnosed with central precocious puberty (PP) with early pubertal development to determine whether PP is a clinical manifestation of MDs. We also examined the clinical, auxiological, laboratory, and radiological parameters after 1 year of gonadotropin-releasing hormone treatment for central PP. Among the 140 girls with MDs, 29 had early pubertal development and underwent endocrine evaluation. Ten (7.1%) patients were diagnosed with central PP; the prevalence of central PP was higher than was that previously thought. Patients with central PP exhibited bone age advancement over 1 year and increased sex hormone levels despite their young age at diagnosis. Serum estradiol levels were significantly higher in younger patients than in older patients (P = 0.004). Patients with central PP treated with gonadotropin-releasing hormone had favorable outcomes, and their pubertal development was suppressed for 1 year.Conclusion: Central PP may be a manifestation of endocrine dysfunction in young girls with MDs. What is Known: • The general characteristics of mitochondrial diseases include developmental delays and retarded growth. • Precocious puberty has rarely been suggested as a clinical manifestation of mitochondrial diseases. What is New: • Among the 140 girls with mitochondrial diseases, 10 (7.1%) were diagnosed with central precocious puberty. • Serum estradiol levels were significantly higher in younger patients than in older patients.

Proximal hyper-intense vessel sign on initial FLAIR MRI in hyper-acute middle cerebral artery ischemic stroke: a retrospective observational study.

BACKGROUND: A hyper-intense vessel sign on fluid attenuated inversion recovery magnetic resonance imaging (FHV) represents slow blood flow in the cerebral arteries. PURPOSE: To investigate the relationship between the proximal FHV (pFHV) on initial magnetic resonance imaging (MRI) and the status of the culprit vessel (stenosis, obstruction) in hyper-acute strokes affecting the territory of the middle cerebral artery (MCA). MATERIAL AND METHODS: The study participants consisted of 105 patients presenting to the emergency department (ED) with acute MCA infarction within 4.5 h of onset of symptoms. Patients underwent brain MRI within 45 min of arrival at the ED and angiography within 2 h of arrival. Culprit vessel status and presence of a pFHV on initial MRI were investigated retrospectively. RESULTS: The pFHV was observed in 71/105 (67.6%) patients who presented with a hyper-acute MCA infarction. All patients with hyper-acute MCA infarction caused by internal carotid artery (90.6% caused by M1 occlusion, 92.9% caused by M2 occlusion) showed a pFHV on initial MRI. After logistic regression analysis, the presence of a pFHV showed significant positive correlation with large vessel occlusion (adjusted odds ratio [OR] 34.533, 95% confidence interval [CI] 9.781-121.926; P < 0.001). A pFHV was not associated with severe large vessel stenosis. CONCLUSION: A pFHV is independently representative of the acute occlusion of intervention-eligible proximal arteries within the territory of the MCA. If a patient with a hyper-acute MCA infarction shows a pFHV, aggressive flow augmentation strategies and early activation of intervention team should be warranted for best patient outcome.

Comparison of ICC patients with hepatitis B infection to those with no major risk factors for HCC.

BACKGROUND: There has been renewed interest in HBV-associated ICC, because it could share a common carcinogenesis disease process with HCC. We investigated whether there is a difference in clinical outcome between ICC patients with HBV infection and those without any major risk factors for HCC. METHODS: A total of 253 curatively resected, surgically diagnosed ICC patients were analyzed and divided into two groups according to the presence or absence of major risk factors for HCC: an HBV group (n = 45) and a non-HCC-risk (NHR) group (n = 208). RESULTS: Lymph node metastasis was more frequently observed in the NHR group (HBV vs. NHR: 8.89% vs. 24.52%, P = 0.027). Patients in the HBV group demonstrated more favorable survival than those in the NHR group. However, this difference was not statistically significant (5-year survival rate, 54.7% vs. 42.3%, P = 0.128). Cumulative recurrence rate in the HBV group was 62.2%, which was not significantly different from 63.0% in the NHR group (P = 1.000). CONCLUSION: This study found that while ICC patients with HBV infection showed some favorable tumor characteristics, patients' stage-specific survival and recurrence rates were not significantly different compared to those without any major risk factors for HCC.

Myelin degeneration induced by mutant superoxide dismutase 1 accumulation promotes amyotrophic lateral sclerosis.

Myelin is a specialized membrane that wraps around nerve fibers and is essential for normal axonal conduction in neurons. In the central nervous system, oligodendrocytes are responsible for myelin formation. Recent studies have reported pathological abnormalities in oligodendrocytes in human patients with amyotrophic lateral sclerosis (ALS) and a mouse model of ALS expressing the G93A mutation of the human superoxide dismutase 1 (mtSOD1). However, it is unclear whether oligodendrocyte pathology in ALS represents the primary dysfunction induced by mtSOD1 and how mtSOD1 contributes to oligodendrocyte degeneration and ALS pathogenesis. We analyzed GAL4-VP16-UAS transgenic zebrafish selectively expressing mtSOD1 in mature oligodendrocytes. We observed that mtSOD1 directly induced oligodendrocyte degeneration by disrupting the myelin sheath and downregulating monocarboxylate transporter 1 (MCT1), thereby causing spinal motor neuron degeneration. Pathological changes observed in this transgenic zebrafish were similar to the pathology observed in the SOD1G93A mouse model of ALS, which is characterized by expression of mtSOD1 in all cells. In addition, oligodendrocyte dysfunction induced by mtSOD1 was associated with anxiety-related behavioral abnormalities, learning impairments, and motor defects in the early symptomatic stage. We also found that treatment with potassium channel inhibitors rescued behavioral abnormalities without rescuing MCT1 expression, suggesting that myelin disruption induces behavioral abnormalities independently of MCT1. These results indicate that mtSOD1-induced dysfunction of mature oligodendrocytes is sufficient to induce motor neuron degeneration, thus informing future therapeutic strategies targeted at oligodendrocytes in ALS.

Utilization of Coronary Artery to Aorta for the Early Detection of Kawasaki Disease.

Timely diagnosis of coronary involvement is paramount in Kawasaki disease (KD) as it can be associated with long-term morbidity. However, echocardiographic measurements of coronary artery dilation in KD are inconsistent and not proficient for all abnormal arteries. The purpose of this study was to investigate more valuable indices and determine their sensitivity and specificity for early diagnosis of coronary involvement in KD. We performed this retrospective study in 218 children. All patients underwent laboratory and echocardiographic evaluations upon admission. We measured the size of the left main coronary artery (LMA), left anterior descending coronary artery (LAD), right coronary artery (RCA), and aorta (Ao), and calculated the LMA/Ao, LAD/Ao, and RCA/Ao ratios. We also calculated the cut-off values of each index using receiver operating characteristic curves. LMA, LAD, and RCA measurements did not correlate with white blood cell count, platelet count, erythrocyte sedimentation rate, C-reactive protein level, or brain natriuretic peptide level. The LMA measurement was associated with hemoglobin, hematocrit, and iron saturation. LAD/Ao was correlated with white blood cell and platelet counts (P < 0.05), whereas RCA/Ao was correlated with ferritin level (P < 0.05). The cut-off value of LMA/Ao was 0.2, with a sensitivity of 85% and specificity of 70%. Individual coronary artery/Ao ratios might provide helpful insight for detection of coronary abnormality in KD in the acute phase. Further investigation is essential to clarify prompt early diagnosis of coronary involvement in KD.

Hypomyelination and cognitive impairment in mice lacking CD133 (Prominin-1).

The CD133 antigen, also known as prominin-1, is a glycoprotein that specifically localizes to plasma membrane protrusions. The precise function of CD133 remains unknown, but it is expressed in various progenitor cells including those derived from the neural and hematopoietic system, as well as different tissues. In the adult mouse brain, CD133 is highly expressed in white matter. Here, we performed immunohistochemical staining and electron microscopy to demonstrate that mice lacking CD133 (CD133-/-) exhibit decreased myelin in the corpus callosum, the largest white matter tract in the brain. Hypomyelination in CD133-/- mice was associated with fewer oligodendrocyte progenitor cells and mature oligodendrocytes. Behavioral analyses revealed that significantly impaired object recognition memory and altered Y-maze performance by CD133-/- mice compared with wild-type mice, suggesting perturbed cognitive performance. These results suggest that CD133 regulates myelination and understanding the underlying molecular mechanisms may guide the development of novel therapeutic strategies for diseases characterized by myelin deficiency.

Manikin study showed that counting inflation breaths out loud improved the speed of resuming chest compressions during two-person paediatric cardiopulmonary resuscitation.

AIM: We investigated whether counting inflation breaths out loud during cardiopulmonary resuscitation (CPR) led to an earlier resumption of chest compressions. METHODS: In this randomised controlled manikin simulation study, conducted from February 2015 to April 2015, 32 fourth-year Korean medical students, equally divided into study and control groups, performed 10 cycles of 15:2 CPR while administering inflation breaths using a bag mask. The first study participant counted the number of inflation breaths out loud, and the second study participant was told to perform chest compressions as soon as they heard their colleague say two. The control group did not count out loud. The groups were blinded to the study outcomes and put in separate rooms. RESULTS: The median chest compression interruption time was shorter in the study group than the control group (40 vs 46 seconds, p < 0.01, r = 0.70), and the median chest compression fraction (CCF) was higher (68 vs 62%, p < 0.01, r = 0.71). Other quality outcomes related chest compressions and ventilation did not differ between the groups. CONCLUSION: Counting the number of inflation breaths out loud was a simple method that improved the speed of resuming chest compressions and increased CCFs in 15:2 CPR.