Myeong-Soo Park

Genome Sequence of the Probiotic Bacterium Bifidobacterium animalis subsp. lactis AD011

Bifidobacterium animalis subsp. lactis is a probiotic bacterium that naturally inhabits the guts of most mammals, including humans. Here we report the complete genome sequence of B. animalis subsp. lactis AD011 that was isolated from an infant fecal sample. Biological functions encoded in a single circular chromosome of 1,933,695 bp, smallest among the completely sequenced bifidobacterial genomes, are suggestive of their probiotic functions, such as utilization of bifidogenic factors and a variety of glycosidic enzymes and biosynthesis of polysaccharides.

Histologic Analysis of Retrieved Clots in Acute Ischemic Stroke: Correlation with Stroke Etiology and Gradient-Echo MRI

BACKGROUND AND PURPOSE: It is unclear whether clot composition analysis is helpful to predict a stroke mechanism in acute large vessel occlusion. In addition, the relationship between early vessel signs on imaging studies and clot compositions has been poorly understood. The purpose of this study was to elucidate the relationship between clot composition and stroke etiology following mechanical thrombectomy and to investigate the effect of varied clot compositions on gradient-echo MR imaging of clots. MATERIALS AND METHODS: Histopathologic analysis of retrieved clots from 37 patients with acute MCA occlusion was performed. Patients underwent gradient-echo imaging before endovascular therapy. Retrieved clots underwent semiquantitative proportion analysis to quantify red blood cells, fibrin, platelets, and white blood cells by area. Correlations between clot compositions and stroke subtypes and susceptibility vessel signs on gradient-echo imaging were assessed. RESULTS: Stroke etiology was classified as cardioembolism in 22 patients (59.4%), large-artery atherosclerosis in 8 (21.6%), and undetermined in 7 (18.9%). The clots from cardioembolism had a significantly higher proportion of red blood cells (37.8% versus 16.9%, P = .031) and a lower proportion of fibrin (32.3% versus 48.5%, P = .044) compared with those from large-artery atherosclerosis. The proportion of red blood cells was significantly higher in clots with a susceptibility vessel sign than in those without it (48.0% versus 1.9%, P < .001), whereas the proportions of fibrin (26.4% versus 57.0%, P < .001) and platelets (22.6% versus 36.9%, P = .011) were significantly higher in clots without a susceptibility vessel sign than those with it. CONCLUSIONS: The histologic composition of clots retrieved from cerebral arteries in patients with acute stroke differs between those with cardioembolism and large-artery atherosclerosis. In addition, a susceptibility vessel sign on gradient-echo imaging is strongly associated with a high proportion of red blood cells and a low proportion of fibrin and platelets in retrieved clots.

Acute Basilar Artery Occlusion: Outcome of Mechanical Thrombectomy with Solitaire Stent within 8 Hours of Stroke Onset

BACKGROUND AND PURPOSE: Mechanical thrombectomy with a stent retriever applied shortly after symptom onset could increase good functional outcomes and improve survival in patients with acute basilar artery occlusion, but this has not yet been studied. This study evaluated the efficacy and safety of mechanical thrombectomy with a Solitaire stent within 8 hours of stroke onset in patients with acute basilar artery occlusion. MATERIALS AND METHODS: We analyzed 25 consecutive patients with acute basilar artery occlusion who were treated with mechanical thrombectomy by use of the Solitaire stent within 8 hours of stroke symptom onset. Successful recanalization was defined as TICI grade 2b or 3. Good outcome was defined as mRS score of 0–2 at 3 months. Clinical and radiologic data in patients with good outcomes were compared with those with poor outcomes. RESULTS: Successful recanalization was achieved in 96% (24/25) of patients, and 48% (12/25) of patients had good outcomes. Eighty-eight percent (22/25) of patients survived to 3 months. The median NIHSS score on admission was significantly lower in patients with good outcomes than in those with poor outcomes (9.5 versus 14, P = .005). Procedure-related complications occurred in 2 patients (8%). No symptomatic intracerebral hemorrhages occurred. CONCLUSIONS: The current study suggests that mechanical thrombectomy by use of a Solitaire stent within 8 hours of stroke onset increases good outcomes and improves survival in patients with acute basilar artery occlusion.

Expression of Rice Glutamate Decarboxylase in Bifidobacterium Longum Enhances γ-Aminobutyric Acid Production

Bifidobacteria are important for the production of fermented dairy products and probiotic formulas but have a low capacity for γ-aminobutyric acid (GABA) production. To develop a Bifidobacterium strain with an enhanced GABA production, we transformed Bifidobacterium longum with a rice glutamate decarboxylase (OsGADC−) gene by electroporation. When the transformed strain was cultured in medium containing monosodium glutamate, the amount of GABA increased significantly compared with those of untransformed Bifidobacterium. Thus, by introducing a plant derived GAD gene, a Bifidobacterium strain has been genetically engineered to produce high levels of GABA from glutamate.

Therapeutic Effects of Fermented Red Ginseng in Allergic Rhinitis: A Randomized, Double-Blind, Placebo-Controlled Study

Purpose Allergic rhinitis is clinically defined as a disorder of the nose induced by IgE mediated inflammation after allergen exposure of the nasal mucosa. Many reports have stated that Panax ginseng and fermented red ginseng have anti-inflammatory effects, especially against Th2-type inflammation. This study was conducted to evaluate the therapeutic effects of fermented red ginseng in allergic rhinitis. Methods In this 4-week, double-blind, placebo-controlled study, 59 patients with persistent perennial allergic rhinitis were randomly divided into two groups: those receiving fermented red ginseng tablets (experimental group) and those receiving placebo (control group). The primary efficacy variable was the total nasal symptom score (TNSS; rhinorrhea, sneezing, itchy nose, and nasal congestion). Secondary efficacy variables were the Rhinitis Quality of Life (RQoL) score and skin reactivity to inhalant allergens, as determined by the skin prick test. Results There was no significant difference in the TNSS score and TNSS duration score between the experimental and placebo groups in weeks 1, 2, 3, or 4. For nasal congestion, fermented red ginseng was significantly effective (P<0.005), while placebo caused no change. The activity and emotion of RQoL improved markedly secondary to treatment with fermented red ginseng (P<0.05), while placebo caused no change. Additionally, fermented red ginseng reduced skin reactivity to sensitized perennial allergens (P<0.05). Fermented red ginseng was well tolerated. Conclusions Fermented red ginseng improved nasal congestion symptoms and RQoL in patients with perennial allergic rhinitis.

Low-Dose Intra-Arterial Urokinase and Aggressive Mechanical Clot Disruption for Acute Ischemic Stroke after Failure of Intravenous Thrombolysis

BACKGROUND AND PURPOSE: Intravenous (IV) thrombolysis often fails to achieve recanalization of occluded cerebral arteries, especially in patients with proximal large arterial occlusions. The goal of this study was to assess the feasibility, safety, and efficacy of low-dose intra-arterial (IA) urokinase and aggressive mechanical clot disruption (AMCD) after failure of IV thrombolysis for acute ischemic stroke. MATERIALS AND METHODS: We prospectively enrolled 12 patients with acute ischemic stroke who initially received IV recombinant tissue plasminogen activator (rtPA) and were subsequently treated with combined low-dose IA urokinase and AMCD. Time to treatment, urokinase dose, duration of the procedure, recanalization rates, and symptomatic hemorrhage were analyzed. Clinical outcome measures were assessed on admission and at discharge (National Institutes of Health Stroke Scale [NIHSS]), and at 3 months after treatment (modified Rankin Scale [mRS]). RESULTS: Median NIHSS score on admission was 17. Median time from symptom onset to IV rtPA was 120 minutes, and median time from symptom onset to IA therapy was 230 minutes. The median duration of IA therapy was 55 minutes. Median dose of urokinase was 300,000 U. Recanalization (thrombolysis in cerebral ischemia grade II or III) was achieved in all patients. No procedure-related complications were observed. There was no symptomatic hemorrhage. At discharge, median NIHSS score was 3. The 3-month outcome was excellent (mRS, 0–1) in 8 patients, good (mRS, 2) in 1 patient, and poor (mRS, 3–5) in 3 patients. There was no hospital or 3-month mortality. CONCLUSIONS: In this study, combination therapy with low-dose IA urokinase and AMCD is safe and effective after failed IV thrombolysis in patients with acute ischemic stroke. A high rate of recanalization, low rate of symptomatic hemorrhage, and excellent functional outcome can be achieved.

The serum ferritin level is an important predictor of hemorrhagic transformation in acute ischaemic stroke.

Background and purpose:  Because hemorrhagic transformation (HT) is associated with morbidity and mortality, we need a better understanding of the factors that predict HT after ischaemic stroke. HT is a well‐known factor that limits the use of thrombolytics and it negates the effect of treatment. This study investigated whether a high serum ferritin level is associated with HT in acute ischaemic stroke.

Thrombolysis as a factor associated with favorable outcomes in patients with unclear-onset stroke.

Background and purpose:  Clinical and radiological features of patients with unclear‐onset stroke do not differ significantly from those with known‐onset stroke. There is a lack of evidence for the safety and efficacy of thrombolysis in patients with unclear‐onset stroke. We sought to provide supportive data on the safety and efficiency of thrombolysis in patients with unclear‐onset stroke.

Negative Susceptibility Vessel Sign and Underlying Intracranial Atherosclerotic Stenosis in Acute Middle Cerebral Artery Occlusion

BACKGROUND AND PURPOSE: The role of MR imaging in predicting underlying intracranial atherosclerotic stenosis before endovascular stroke therapy has not been studied. Our aim was to determine the diagnostic value of the negative susceptibility vessel sign on T2*-weighted gradient-echo MR imaging for predicting underlying intracranial atherosclerotic stenosis in patients with acute MCA occlusion. MATERIALS AND METHODS: Ninety-one consecutive patients with acute stroke because of MCA occlusion underwent gradient-echo MR imaging and MRA before endovascular therapy. The negative susceptibility vessel sign was defined as an absence of a hypointense signal change within the occluded MCA on gradient-echo imaging. Underlying intracranial atherosclerotic stenosis was determined by conventional angiography. The sensitivity, specificity, predictive values, and accuracy of the negative susceptibility vessel sign for predicting the presence of underlying intracranial atherosclerotic stenosis were assessed. RESULTS: The negative susceptibility vessel sign was identified in 42 (46.1%) of 91 patients, and 18 (19.8%) patients had an underlying intracranial atherosclerotic stenosis responsible for acute ischemic symptoms. The negative susceptibility vessel sign was more frequently observed in patients with intracranial atherosclerotic stenosis than in those without it (100% versus 32.9%, P < .001). In the prediction of an underlying intracranial atherosclerotic stenosis, the negative susceptibility vessel sign had 100% sensitivity, 67.1% specificity, 42.9% positive predictive value, 100% negative predictive value, and an accuracy of 73.6%. CONCLUSIONS: The negative susceptibility vessel sign on gradient-echo MR imaging is a sensitive marker with a high negative predictive value for the presence of an underlying intracranial atherosclerotic stenosis in patients with acute ischemic stroke because of MCA occlusions. The susceptibility vessel sign can be used in decision-making when performing subsequent endovascular revascularization therapy in patients with acute MCA occlusions.

Prediction of hemorrhagic transformation in acute ischaemic stroke by micro‐ and macroalbuminuria after intravenous thrombolysis

Hemorrhagic transformation (HT) is one of the most problematic complications to arise from intravenous thrombolysis (IVT). This study was conducted to assess whether micro‐ and macroalbuminuria could be associated with HT after IVT in patients with acute ischaemic stroke, and to investigate whether the value of urinary albumin‐to‐creatinine ratios would correlate with the degree of HT.