Three-dimensional hydrodynamic-eutrophication model (HEM-3D): application to Kwang-Yang Bay, Korea.

The purpose of this paper is twofold: to describe the water quality model of Three-Dimensional Hydrodynamic-Eutrophication Model (HEM-3D) and to present an application of HEM-3D to a coastal system in Korea. HEM-3D, listed as a tool for the development of Total Maximum Daily Load by US Environmental Protection Agency, is a general-purpose modeling package for simulation of the flow field, transport, and eutrophication processes throughout the water column and of diagenetic processes in the benthic sediment. This paper describes the water quality model of HEM-3D with emphasis on its unique features. Excessive loadings of organic wastes have significantly deteriorated water quality conditions of Korean coastal waters. This paper presents an application of HEM-3D to Kwang-Yang Bay, a coastal system in Korea, which is one of the first water quality modeling efforts for Korean coastal waters accompanied by a relatively comprehensive field program. The current status of data availability for water quality modeling in Korea is discussed.

Outcome of Extracorporeal Ventricular Assist Device for Cardiogenic Shock as a Bridge to Transplantation

Background@#The extracorporeal ventricular assist device (e-VAD) system is designed for left ventricular support using a permanent life support console. This study aimed to determine the impact of temporary e-VAD implantation bridging on posttransplant outcomes. @*Methods@#We reviewed the clinical records of 6 patients with the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile 1, awaiting heart transplantation, who were provided with temporary e-VAD from 2018 to 2019. The circuit comprised a single centrifugal pump without an oxygenator. The e-VAD inflow cannula was inserted into the apex of the left ventricle, and the outflow cannula was positioned in the ascending aorta. The median follow-up duration was 8.4±6.9 months. @*Results@#After e-VAD implantation, lactate dehydrogenase levels significantly decreased, and Sequential Organ Failure Assessment scores significantly improved. Bedside rehabilitation was possible in 5 patients. After a mean e-VAD support duration of 14.5±17.3 days, all patients were successfully bridged to transplantation. After transplantation, 5 patients survived for at least 6 months. @*Conclusion@#e-VAD may reverse end-organ dysfunction and improve outcomes in INTERMACS I heart transplant patients.

The First Pediatric Heart Transplantation Bridged by a Durable Left Ventricular Assist Device in Korea

Treatment options for children with end-stage heart failure are limited. We report the first case of a successful pediatric heart transplantation bridged with a durable left ventricular assist device in Korea. A 10-month-old female infant with dilated cardiomyopathy and left ventricular non-compaction was listed for heart transplantation. During the waiting period, the patient’s status deteriorated. Therefore, we decided to provide support with a durable left ventricular assist device as a bridge to transplantation. The patient was successfully bridged to heart transplantation with effective support and without any major adverse events.

Plugging the leak: barrier island restoration following Hurricane Katrina enhances larval retention and improves salinity regime for oysters in Mobile Bay, Alabama.

Changes in geomorphology of estuaries are common following major perpetuations such as hurricanes and may have profound impacts on biological systems. Hurricane Katrina in 2005 created a new pass, called Katrina Cut, halving Dauphin Island in Mobile Bay, Alabama. Significant decline in oyster population at Cedar Point Reef, the primary oyster harvest grounds in Mobile Bay, had persisted since then until the Cut was artificially closed in 2010. A bio-physical model for hydrodynamics and oyster larval transport was used to evaluate two potential mechanisms responsible for oyster population declines: salinity changes in the context of oyster habitat suitability and retention of oyster larvae. The model results revealed that when open Katrina Cut increased salinity at Cedar Point Reef. During high freshwater discharge, in particular, water exchange through Katrina Cut increased the bottom salinity from <5 psu to well over 15 (sometimes >20) psu during the tropic tides. Elevated salinities are associated with greater predation on oysters and higher disease incidence. The presence of the Katrina Cut also reduced larval retention in the spawning area regardless of tidal or river discharge conditions. We conclude that closing the Cut likely improved conditions for oysters within Mobile Bay and eastern Mississippi Sound and that these improved conditions have contributed to increased oyster landings.

Successful Surgical Treatment of a Recurrent Esophageal Malignant Gastrointestinal Neuroectodermal Tumor

Malignant gastrointestinal neuroectodermal tumor (GNET) is a very rare disease entity, especially in the esophagus. The diagnosis of GNET is based on histologic, immunohistochemical, and genetic findings. The choice of treatment is complete resection, and further treatment options can be considered. Herein, we describe a case of successful surgical treatment of a 23-year-old man with recurrent malignant esophageal GNET.

Clozapine Induced Neuroleptic Malignant Syndrome / 대한중환자의학회지

Neuroleptic malignant syndrome is a rare, but potentially life-threatening adverse event associated with the use of neuroleptic agents. We describe the case of a 47-year-old schizophrenic woman who was treated with clozapine for years. The patient developed acute renal failure with pulmonary edema, and underwent mechanical ventilation and hemodialysis.

Clozapine Induced Neuroleptic Malignant Syndrome / 대한구급학회지

Neuroleptic malignant syndrome is a rare, but potentially life-threatening adverse event associated with the use of neuroleptic agents. We describe the case of a 47-year-old schizophrenic woman who was treated with clozapine for years. The patient developed acute renal failure with pulmonary edema, and underwent mechanical ventilation and hemodialysis.

Emerging Surgical Strategies of Intractable Frontal Lobe Epilepsy with Cortical Dysplasia in Terms of Extent of Resection

OBJECTIVE: Cortical dysplasia (CD) is one of the common causes of epilepsy surgery. However, surgical outcome still remains poor, especially with frontal lobe epilepsy (FLE), despite the advancement of neuroimaging techniques and expansion of surgical indications. The aim of this study was to focus on surgical strategies in terms of extent of resection to improve surgical outcome in the cases of FLE with CD. METHODS: A total of 11 patients of FLE were selected among 67 patients who were proven pathologically as CD, out of a total of 726 epilepsy surgery series since 1992. This study categorized surgical groups into three according to the extent of resection : 1) focal corticectomy, 2) regional corticectomy, and 3) partial functional lobectomy, based on the preoperative evaluation, in particular, ictal scalp EEG onset and/or intracranial recordings, and the lesions in high-resolution MRI. Surgical outcome was assessed following Engel's classification system. RESULTS: Focal corticectomy was performed in 5 patients and regional corticectomy in another set of 5 patients. Only 1 patient underwent partial functional lobectomy. Types I and II CD were detected with the same frequency (45.45% each) and postoperative outcome was fully satisfactory (91%). CONCLUSION: The strategy of epilepsy surgery is to focus on the different characteristics of each individual, considering the extent of real resection, which is based on the focal ictal onset consistent with neuroimaging, especially in the practical point of view of neurosurgery.

Very Late Stent Thrombosis after Sole Stent-Assisted Coiling at the Paraclinoid Giant Aneurysm : Could Prophylactic Antiplatelet Therapy Be Ceased at the Only 1 Year after Procedure?

Stent thrombosis is a major limitation of stent-assisted coiling, which is an effective method for treating wide-necked aneurysms. Although early in-stent thrombosis has been reported, very late stent thrombosis (VLST) (>1 year) has not been reported following implantation of a single self-expandable stent designed for coiling. Herein, the authors present a case of VLST that occurred 14 months after single stent implantation in a large paraclinoid aneurysm with an ultra-wide neck involving the parent artery circumferentially. This case indicates the need for establishing guidelines regarding the optimal duration of prophylactic antiplatelet therapy following stent-assisted coiling, which remains undefined in the neuroendovascular field.

B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction

CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although alpha-galactosylceramide (alpha-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-gamma by NKT cells, concomitant with a decreased level of IL-4, in the circumstance of co-culture of DCs and B Cells. Remarkably, the response promoted by B cells was dependent on CD1d expression of B cells.

The Surgical Outcomes of Clavicle Lateral End Fractures Fixed with the Oblique T Locking Compession Plate

PURPOSE: The purpose of this study is to evaluate the surgical outcomes of the clavicle lateral end fracture fixed with an oblique T locking compression plate (LCP). MATERIALS AND METHODS: Fourteen clavicle lateral end fractures were fixed with the oblique T-LCP and followed up for at least 1 year after the surgery. Thirteen cases were unstable Neer type II fractures and one case was nonunion of the Neer type I fracture. The mean age was 46 years of age (range, 26~70). In ten cases, augmenting sutures with the absorbable suture material were placed in the coraco-clavicular ligament and around the plate and the clavicle to improve the stability of fracture fixation. Autogenous iliac bone graft was done in four cases. The clinical outcomes were evaluated by using UCLA scoring system and KSS (Korean Shoulder Score). RESULTS: The mean UCLA score was 33.5 and the mean KSS was 94.9. Average time of bone union was 11.9 weeks (range, 6~28), including 1 case with a delayed union. There was no complication such as loss of fixation or nonunion. CONCLUSION: Fixation with the oblique T-LCP is a good option providing reliable functional results in clavicle lateral end fractures.

Superficial Peroneal Nerve Injury Following Ankle Sprain / 대한스포츠의학회지

Lateral ankle sprains are one of the most common injuries to the lower extremity. Most of them well respond to conservative treatments. However, simultaneous peroneal nerve injuries may occur rarely following lateral ankle ligamentous injuries. We report a case presents superficial peroneal nerve injury with dorsal foot pain lasting for more than 2 months after lateral ankle sprain and review the literature.

The requirement of natural killer T-cells in tolerogenic APCs-mediated suppression of collagen-induced arthritis

TGF-beta-induced tolerogenic-antigen presenting cells (Tol-APCs) could induce suppression of autoimmune diseases such as collagen-induced arthritis (CIA) and allergic asthma. In contrast, many studies have shown that NKT cells are involved in the pathogenesis of Th1-mediated autoimmune joint inflammation and Th2-mediated allergic pulmonary inflammation. In this study, we investigated the effect of CD1d-restricted NKT cells in the Tol-APCs-mediated suppression of autoimmune disease using a murine CIA model. When CIA-induced mice were treated with Tol-APCs obtained from CD1d+/- or CD1d-/- mice, unlike CD1d+/- APCs, CD1d-/- Tol-APCs failed to suppress CIA. More specifically, CD1d-/- Tol-APCs failed to suppress the production of inflammatory cytokines and the induction of Th2 responses by antigen-specific CD4 T cells both in vitro and in vivo. Our results demonstrate that the presence of CD1d-restricted NKT cells is critical for the induction of Tol-APCs-mediated suppression of CIA.

TGF-beta-treated antigen presenting cells suppress collagen-induced arthritis through the promotion of Th2 responses

Collagen-induced arthritis (CIA) is mediated by self-reactive CD4+ T cells that produce inflammatory cytokines. TGF-beta2-treated tolerogenic antigen-presenting cells (Tol-APCs) are known to induce tolerance in various autoimmune diseases. In this study, we investigated whether collagen-specific Tol-APCs could induce suppression of CIA. We observed that Tol-APCs could suppress the development and severity of CIA and delay the onset of CIA. Treatment of Tol-APCs reduced the number of IFN-gamma- and IL-17-producing CD4+ T cells and increased IL-4- and IL-5-producing CD4+ T cells upon collagen antigen stimulation in vitro. The suppression of CIA conferred by Tol-APCs correlated with their ability to selectively induce IL-10 production. We also observed that treatment of Tol-APCs inhibited not only cellular immune responses but also humoral immune responses in the process of CIA. Our results suggest that in vitro-generated Tol-APCs have potential therapeutic value for the treatment of rheumatoid arthritis as well as other autoimmune diseases.

Repetitive Insufficiency Fractures of the Femoral Shaft: A Case Report

Stress fractures occur when the loads applied to a bone exceed the mechanical resistance and fall into two groups. Fatigue fractures, in which abnormal mechanical stress is applied to a normal bone, and insufficiency fractures, in which fracture occurs when stress of normal activity is applied to a bone that has decreased elastic resistance. Femoral shaft insufficiency fractures are reported rarely in patients with postmenopausal osteoporosis. We report a case of repetitive insufficiency fractures of the femoral shaft in 70 year-old female with marked osteoporosis.

A New Reporter Vector System Based on Flow-Cytometry to Detect Promoter Activity

In this study, we report the development of a new dual reporter vector system for the analysis of promoter activity. This system employs green fluorescence emitting protein, EGFP, as a reporter, and uses red fluorescence emitting protein, DsRed, as a transfection control in a single vector. The expression of those two proteins can be readily detected via flow cytometry in a single analysis, with no need for any further manipulation after transfection. As this system allows for the simultaneous detection of both the control and reporter proteins in the same cells, only transfected cells which express the control protein, DsRed, can be subjected to promoter activity analysis, via the gating out of all un-transfected cells. This results in a dramatic increase in the promoter activity detection sensitivity. This novel reporter vector system should prove to be a simple and efficient method for the analysis of promoter activity.

Posterior Epidural Migration of a Sequestrated Intervertebral lumbar Disc with Cauda Equina Syndrome: Two Cases Report / 대한척추외과학회지

Posterior epidural migration of a sequestrated intervertebral lumbar disc with cauda equina syndrome is quite rare. This paper reports two unusual cases of posterior epidural migration of a sequestrated intervertebral lumbar disc with cauda equina syndrome to emphasize the importance of early diagnosis and complete decompression.

Dual action of d-tubocurarine on large-conductance Ca2+-activated K+ channels from rat brain reconstituted into planar lipid bilayer

Using the planar lipid bilayer method, we investigated the effect of d-tubocurarine (dTC) on the extracellular side of large-conductance Ca2+-activated K+ channel from rat brain. When the initial open probability (Po) of the channel was relatively high, dTC decreased channel activity in a concentration dependent manner. In contrast, when the initial Po was lower, sub-micro molar dTC increased channel activity by destabilizing the closed states of the channel. Further addition of dTC up to micro molar range decreased channel activity. This dual effect of dTC implicates that there exist at least two different binding sites for dTC.

Effects of t-butyl hydrogen peroxide on single SR calcium release channels

Using lipid bilayer reconstitution technique, we investigated the oxidation effect of t-butyl hydrogen peroxide (tBHP) on the single channel activity of the sarcoplasmic reticulum (SR) calcium release channels isolated from canine latissimus dorsi muscles. When 0.7% tBHP was added in the cytosolic side, the channel activity became suppressed (n = 7), and it was recovered by changing the solution to the control solution. The suppression was due to the change in the gating mode of the channel: before tBHP the channel opened to four sub-conductance levels, but it opened to only one level after tBHP. These effects by tBHP were different from the previous finding using hydrogen peroxide (H2O2), which may be explained by different oxidation patterns between the two oxidants.

4-Aminopyridine (4-AP) augments Ca(2+)-dependent action potential and changes oscillatory firing patterns in rat cerebellar Purkinje cells

Intracellular recordings in cerebellar slice preparation showed that applications of 4-AP altered the pattern of oscillatory firing activity in Purkinje cells (PCs), especially yielding pronounced changes in action potential shape. 4-AP increased the amplitude and duration of action potential significantly and decreased the spike frequency. After 4-AP application, the duration of bursting was prolonged and the duration of after-burst hyperpolarization was progressively shortened. In all PCs tested, the rhythmicity of oscillatory firing activity was abolished completely at the steady state. These results suggest that 4-AP-sensitive currents determine the shape and frequency of individual Ca(2+)-dependent action potentials as well as maintaining oscillatory firing activity in PCs.