Hypertensive brainstem encephalopathy involving deep supratentorial regions: does only blood pressure matter?

We report on a 42-year-old female patient who presented with high arterial blood pressure of 245/150 mmHg and hypertensive brainstem encephalopathy that involved the brainstem and extensive supratentorial deep gray and white matter. The lesions were nearly completely resolved several days after stabilization of the arterial blood pressure. Normal diffusion-weighted imaging findings and high apparent diffusion coefficient values suggested that the main pathomechanism was vasogenic edema owing to severe hypertension. On the basis of a literature review, the absolute value of blood pressure or whether the patient can control his/her blood pressure seems not to be associated with the degree of the lesions evident on magnetic resonance imaging. It remains to be determined if the acceleration rate and the duration of elevated arterial blood pressure might play a key role in the development of the hypertensive encephalopathy pattern

AJK2011-07008 NUMERICAL SIMULATION OF UNDERWATER PROPULSOR USING AN UNSTRUCTURED OVERSET MESH TECHNIQUE

ABSTRACT In the present study, the hydrodynamic characteristics of underwater propulsors have been numerically investigated using a RANS flow solver based on pseudo-compressibility. A vertexcentered finite-volume method was utilized in conjunction with 2nd-order Roe's FDS to discretize the inviscid fluxes. The viscous fluxes were computed based on central differencing. The Spalart-Allmaras one equation model was employed for the closure of turbulence. A dual-time stepping method and the Gauss-Seidel iteration were used for unsteady time integration. An unstructured overset mesh technique was adopted to treat the relative motion between multiple bodies. Calculations were made for the DTRC4119 marine propeller at several advancing ratios. Additional calculations were also made for multipleblade-row underwater propulsors. Reasonable agreements were obtained between the present results and the experiment for the pressure coefficients on the blade surface and the integrated blade loadings. The interaction between multiple blade rows and the thrust and torque distributions were also analyzed to investigate the performance of underwater propulsors

Observation of Scarred Modes in Asymmetrically Deformed Microcylinder Lasers

We report observation of lasing in the scarred modes in an asymmetrically deformed microcavity made of liquid jet. The observed scarred modes correspond to morphology-dependent resonance of radial mode order 3 with their Q values in the range of 10^6. Emission directionality is also observed, corresponding to a hexagonal unstable periodic orbit.Comment: 4 pages, 6 figure

Magnetic Resonance Imaging Compatibility of the Polymer-based Cochlear Implant

ObjectivesIn this study, we compared the magnetic resonance (MR) image artifacts caused by a conventional metal-based cochlear implant and a newly developed liquid crystal polymer (LCP)-based device.MethodsThe metal-based cochlear implant system (Nurobiosys Co.) was attached to side of the head of a subject and the LCP-based device was attached to opposite side. In both devices, alignment magnets were removed for safety. Magnetic resonance imaging (MRI) was performed on a widely used 3.0 T and an ultra-high 7.0 T MRI machine. 3.0 and 7.0 T MR images were acquired using T1- and T2*-weighted gradient echo sequences, respectively.ResultsIn the 3.0 T images, the metal-based device on the left side generated the significant amount of artifacts. The MR images in the proximity of the metal package were obscured by the artifacts in both axial and sagittal views. On the other hand, the MR images near the LCP-based device were relatively free from the artifacts and clearly showed the brain structures. 7.0 T MR images showed the more severe distortion in the both sides but the metal-based cochlear implant system caused a much larger obscure area than the LCP-based system.ConclusionThe novel LCP-based cochlear implant provides a good MRI compatibility beyond present-day cochlear implants. Thus, MR images can be obtained from the subjects even with the implanted LCP-based neural prosthetic systems providing useful diagnostic information. Furthermore, it will be also useful for functional MRI studies of the auditory perception mechanism after cochlear implantations as well as for positron emission tomography-MRI hybrid imaging

Kdm3b haploinsufficiency impairs the consolidation of cerebellum-dependent motor memory in mice

Histone modifications are a key mechanism underlying the epigenetic regulation of gene expression, which is critically involved in the consolidation of multiple forms of memory. However, the roles of histone modifications in cerebellum-dependent motor learning and memory are not well understood. To test whether changes in histone methylation are involved in cerebellar learning, we used heterozygous Kdm3b knockout (Kdm3b+/−) mice, which show reduced lysine 9 on histone 3 (H3K9) demethylase activity. H3K9 di-methylation is significantly increased selectively in the granule cell layer of the cerebellum of Kdm3b+/− mice. In the cerebellum-dependent optokinetic response (OKR) learning, Kdm3b+/− mice show deficits in memory consolidation, whereas they are normal in basal oculomotor performance and OKR acquisition. In addition, RNA-seq analyses revealed that the expression levels of several plasticity-related genes were altered in the mutant cerebellum. Our study suggests that active regulation of histone methylation is critical for the consolidation of cerebellar motor memory.This work was supported by grants to S.B.S. and Y.-S.L. (NRF2019R1A4A2001609), Y.-S.L. (NRF-2017M3C7A1026959), and S.J.K. (NRF2018R1A5A2025964) from the National Research Foundation of Korea

Influence of atmospheric dust deposition on sinking particle flux in the northwest Pacific

We examined the flux and composition of sinking particles collected at a water depth of 800 m in the northwest Pacific from November 2017 to August 2018 to assess the impact of dust deposition on organic carbon export. The fluxes of total particulate matter and particulate organic carbon averaged over the study period were 88 ± 63 mg m-2 d-1 and 9.0 ± 5.8 mg m−2 d−1, respectively. Biogenic particles accounted for 82% of the sinking particles, on average. There were two notable pulses in the particle fluxes of both biogenic and lithogenic material in February and May 2018. These flux peaks were decoupled from net primary production in the surface waters but coincided with intervals of high rates of atmospheric dust deposition. The biogenic component of the two peaks was dominated by two different phytoplankton communities, which may have influenced carbon export efficiency. Correlations between the sinking particle flux and the lithogenic flux are found at several locations in the northwest Pacific, implying that East Asian dust deposition has a prevalent influence on the biological pump. Attention should be paid to the effects of changes in the continental dust supply to the oceans on oceanic carbon export

Hepatitis B surface antigen titer is a good indicator of durable viral response after entecavir off-treatment for chronic hepatitis B

Background/Aims Clear indicators for stopping antiviral therapy in chronic hepatitis B (CHB) patients are not yet available. Since the level of hepatitis B surface antigen (HBsAg) is correlated with covalently closed circular DNA, the HBsAg titer might be a good indicator of the off-treatment response. This study aimed to determine the relationship between the HBsAg titer and the entecavir (ETV) off-treatment response. Methods This study analyzed 44 consecutive CHB patients (age, 44.6±11.4 years, mean±SD; men, 63.6%; positive hepatitis B envelope antigen (HBeAg) at baseline, 56.8%; HBV DNA level, 6.8±1.3 log10 IU/mL) treated with ETV for a sufficient duration and in whom treatment was discontinued after HBsAg levels were measured. A virological relapse was defined as an increase in serum HBV DNA level of >2000 IU/mL, and a clinical relapse was defined as a virological relapse with a biochemical flare, defined as an increase in the serum alanine aminotransferase level of >2 × upper limit of normal. Results After stopping ETV, virological relapse and clinical relapse were observed in 32 and 24 patients, respectively, during 20.8±19.9 months of follow-up. The cumulative incidence rates of virological relapse were 36.2% and 66.2%, respectively, at 6 and 12 months, and those of clinical relapse were 14.3% and 42.3%. The off-treatment HBsAg level was an independent factor associated with clinical relapse (hazard ratio, 2.251; 95% confidence interval, 1.076–4.706; P=0.031). When patients were grouped according to off-treatment HBsAg levels, clinical relapse did not occur in patients with an off-treatment HBsAg level of ≤2 log10 IU/mL (n=5), while the incidence rates of clinical relapse at 12 months after off-treatment were 28.4% and 55.7% in patients with off-treatment HBsAg levels of >2 and ≤3 log10 IU/mL (n=11) and >3 log10 IU/mL (n=28), respectively. Conclusion The off-treatment HBsAg level is closely related to clinical relapse after treatment cessation. A serum HBsAg level of <2 log10 IU/mL is an excellent predictor of a sustained off-treatment response in CHB patients who have received ETV for a sufficient duration

Cyanoacrylate injection versus band ligation for bleeding from cardiac varices along the lesser curvature of the stomach

Background/Aims Practice guidelines recommend endoscopic band ligation (EBL) and endoscopic variceal obturation (EVO) for bleeding from esophageal varices and fundal varices, respectively. However, the optimal treatment for bleeding from cardiac varices along the lesser curvature of the stomach (GOV1) remains undefined. This retrospective study compared the efficacy between EBL and EVO for bleeding from GOV1. Methods Patients treated by EBL or EVO via cyanoacrylate injection for bleeding from GOV1 were enrolled. Patients diagnosed with hepatocellular carcinoma or treated with endoscopic injection sclerotherapy were excluded. Results The study included 91 patients treated for bleeding from GOV1. The mean age was 56.3±10.9 years (mean±SD), and 78 of them (85.7%) were men. Overall, 51 and 40 patients were treated with EBL and EVO, respectively. A trend for a higher hemostasis rate was noted in the EVO group (100%) than in the EBL group (82.6%, P=0.078). Varices rebled in 15 patients during follow-up. The rebleeding rate was significantly higher in the EBL group than in the EVO group (P=0.004). During follow-up, 13 patients died (11 in the EBL group and 2 in the EVO group); the survival rate was marginally significant between two groups (P=0.050). The rebleeding-free survival rate was significantly higher in the EVO group than in the EBL group (P=0.001). Conclusions Compared to EBL, EVO offered significantly lower rebleeding rates, significantly higher rebleeding-free survival rates, and a trend for higher hemostasis and survival rates. EVO appears to be the better therapeutic option for bleeding from GOV1

A Prediction Rule to Identify Severe Cases among Adult Patients Hospitalized with Pandemic Influenza A (H1N1) 2009

The purpose of this study was to establish a prediction rule for severe illness in adult patients hospitalized with pandemic influenza A (H1N1) 2009. At the time of initial presentation, the baseline characteristics of those with severe illness (i.e., admission to intensive care unit, mechanical ventilation, or death) were compared to those of patients with non-severe illnesses. A total of 709 adults hospitalized with pandemic influenza A (H1N1) 2009 were included: 75 severe and 634 non-severe cases. The multivariate analysis demonstrated that altered mental status, hypoxia (PaO2/FiO2 ≤ 250), bilateral lung infiltration, and old age (≥ 65 yr) were independent risk factors for severe cases (all P < 0.001). The area under the ROC curve (0.834 [95% CI, 0.778-0.890]) of the number of risk factors were not significantly different with that of APACHE II score (0.840 [95% CI, 0.790-0.891]) (P = 0.496). The presence of ≥ 2 risk factors had a higher sensitivity, specificity, positive predictive value and negative predictive value than an APACHE II score of ≥ 13. As a prediction rule, the presence of ≥ 2 these risk factors is a powerful and easy-to-use predictor of the severity in adult patients hospitalized with pandemic influenza A (H1N1) 2009