1.Hyperosmolar therapy for regulation of cerebral edema and intracranial pressure
Journal of the Korean Medical Association 2023;66(5):297-302
Hyperosmolar therapy is an essential treatment method for increased intracranial pressure and cerebral edema. Mannitol and hypertonic saline are frequently used in clinical practice; however, more helpful recommendations are needed for the optimal management of cerebral edema in terms of the choice, dosage, and timing of these medications. This study aimed to introduce the characteristics and relative strengths of two agents, i.e., mannitol and hypertonic saline, and review clinical data supporting their use in various diseases.Current Concepts: Hyperosmolar therapy reduces intracranial pressure by removing water from the brain tissue and transferring it to the vascular space by creating an osmotic gradient. Mannitol improves cerebral blood flow by reducing the hematocrit, decreasing blood viscosity, and increasing deformability of red blood cells. Hypertonic saline increases intravascular volume, transiently increases cardiac output, and improves tissue oxygen partial pressure in the brain. Hypertonic saline has several advantages over mannitol, including quicker onset and longer-lasting reduction in intracranial pressure. However, no significant differences are noted in clinical, functional outcomes, or mortality between the two treatment agents.Discussion and Conclusion: Both mannitol and hypertonic saline are effective in reducing increased intracranial pressure. Clinicians should be able to select an appropriate agent in different clinical situations based on available evidence and patients’ individual medical conditions.
2.Perfusion and Diffusion Variables Predict Early Neurological Deterioration in Minor Stroke and Large Vessel Occlusion
Dong-Seok GWAK ; Jung-A KWON ; Dong-Hyun SHIM ; Yong-Won KIM ; Yang-Ha HWANG
Journal of Stroke 2021;23(1):61-68
Background:
and Purpose Patients with acute large vessel occlusion (LVO) presenting with mild stroke symptoms are at risk of early neurological deterioration (END). This study aimed to identify the optimal imaging variables for predicting END in this population.
Methods:
We retrospectively analyzed 94 patients from the prospectively maintained institutional stroke registry admitted between January 2011 and May 2019, presenting within 24 hours after onset, with a baseline National Institutes of Health Stroke Scale score ≤5 and anterior circulation LVO. Patients who underwent endovascular therapy before END were excluded. Volumes of Tmax delay (at >2, >4, >6, >8, and >10 seconds), mismatch (Tmax >4 seconds – diffusion-weighted imaging [DWI] and Tmax >6 seconds – DWI), and mild hypoperfusion lesions (Tmax 2–6 and 4–6 seconds) were measured. The association of each variable with END was examined using receiver operating characteristic curves. The variables with best predictive performance were dichotomized at the cutoff point maximizing Youden’s index and subsequently analyzed using multivariable logistic regression.
Results:
END occurred in 39.4% of the participants. The optimal variables were identified as Tmax >6 seconds, Tmax >6 seconds – DWI, and Tmax 4–6 seconds with cut-off points of 53.73, 32.77, and 55.20 mL, respectively. These variables were independently associated with END (adjusted odds ratio [aOR], 12.78 [95% confidence interval (CI), 3.36 to 48.65]; aOR, 5.73 [95% CI, 2.04 to 16.08]; and aOR, 9.13 [95% CI, 2.76 to 30.17], respectively).
Conclusions
Tmax >6 seconds, Tmax >6 seconds – DWI, and Tmax 4–6 seconds could identify patients at high risk of END following minor stroke due to LVO.
3.Effects of Mechanical Stimulation and Scaffolds for Nucleus Pulposus Replacement of Intervertebral Disc.
Sang Hoon HA ; Dong Hwa KIM ; Jung Woog SHIN ; Heui Chul GWAK ; Jang Seok CHOI
Journal of Korean Orthopaedic Research Society 2009;12(2):45-52
PURPOSE: In this study, we investigated the potential of injectable hydrogel scaffolds for the regeneration of nucleus pulposus. MATERIALS AND METHODS: We prepared injectable hydrogels [Chitosan-Pluronic (CP), CP/Osteogenic Protein-1 (CP/OP-1), CP/Gly-Arg-Gly-Asp-Ser (CP/GRGDS), CP/GRGDS/OP-1] for this study. One of the four potential materials was selected through the cell viability tests. For each material, primary cultured nucleus pulposus (NP) cells from New Zealand rabbits were seeded onto each material. For the investigation of the effects of mechanical stimulation, the commercially available bioreactor was used. 0.2 MPa of intermittent hydrostatic pressure was imposed for 3 days after 7th day of seeding with the pattern of 2 min and 15 min for stimulating and resting, respectively. The specimens were harvested at 1, 10, 14 day after seeding for analyses. RESULTS: The MTT assay for 5 days revealed that CP/OP-1 group showed significant increase. The other two groups (CP/GRGDS and CP/GRGDS/OP-1) showed that the proliferation rate increased until 3 days after culture, while it decreased on day 5. The mechanical stimuli induced higher amounts of DNA measured in CP/OP- 1 on day 5 after culture. However, no significant difference was observed between two groups. CONCLUSION: We came to the conclusions that the biochemical environment as well as mechanical stimulation may play an important role in regenerating nucleus pulposus matrix, especially in CP/OP-1 in this study. However, further study are recommended in relation to mechanical effects as well as biochemical conditions.
Bioreactors
;
Cell Survival
;
DNA
;
Hydrogel
;
Hydrogels
;
Hydrostatic Pressure
;
Intervertebral Disc
;
Porphyrins
;
Rabbits
;
Regeneration
;
Seeds
4.Acute Ischemic Stroke Caused by Detachment of Cardiac Papillary Fibroelastomas
Minhee KIM ; Daeun SHIN ; WooChan CHOI ; Dong-Seok GWAK ; Man-Hoon HAN ; Yang-Ha HWANG ; Yong-Won KIM
Journal of the Korean Neurological Association 2022;40(2):148-151
Cardiac papillary fibroelastomas are associated with a high risk of systemic embolization in spite of benign nature. We report a case of 85-year-old patient with left supraclinoid internal carotid artery occlusion who treated with aspiration thrombectomy. Despite of the absence of residual mass on echocardiography, we could analyze pathologic specimens using retrieved embolus and confirmed cardiac papillary fibroelastoma as a rare cause of stroke.
5.Outcome of Conservative Treatment of the Zone I, II 5th Metatarsal Base Fracture under Early Weight-Bearing
Heui-Chul GWAK ; Dae-Hyun PARK ; Jung-Han KIM ; Chang-Rack LEE ; Yong-Uk KWON ; Dong-Seok KIM
The Journal of the Korean Orthopaedic Association 2021;56(2):150-156
Purpose:
To determine how the location, displacement, intra-articular involvement, comminution of a 5th metatarsal base fracture affect results of early weight-bearing treatment.
Materials and Methods:
From January 2013 to July 2017, 34 cases of 34 patients diagnosed with a fracture of the zone I and II 5th metatarsal base were enrolled. The mean follow-up period was 13 months (6–15 months). One patient was excluded as a refracture during the follow-up period, and 33 patients underwent conservative treatment. Anteroposterior, lateral, and simple oblique radiography and computed tomography of the foot were performed to evaluate the location and displacement of the fracture, the degree of joint involvement, and comminution. In all 33 patients, a short leg cast or boot brace was selected immediately after the injury, tolerable weight bearing was allowed. If the pain disappeared, full weight bearing was performed after wearing a plain shoe or postoperative shoe. As a clinical result, the American Orthopedic Foot and Ankle Society (AOFAS) score was evaluated at the final follow-up. During outpatient follow-up, a simple radiograph of the foot was taken to confirm the time of radiological bone union and return to work.
Results:
Nine males and 24 females, with an average age of 48.7 years, were enrolled in the study. Twenty-four patients had zone I fractures, and nine patients had zone II fractures. Twenty-two out of 33 patients had a fracture displacement of 2 mm or more. Nine and five patients had joint involvement and comminution, respectively. There was a statistically significant return to work from zone I to zone II. The AOFAS score was excellent at the final follow-up and there was no significant difference. When classifying and comparing the degree of fracture displacement, joint involvement, and comminution, there were no significant differences in the radiological union time and return to work. In all cases, satisfactory results were obtained at the final follow-up.
Conclusion
Satisfactory clinical results can be obtained by allowing early weight-bearing regardless of the fracture location, displacement, joint involvement, or comminution in zone I and II 5th metatarsal base fractures.
6.Efficient Method for the Rapid Purification of Nosema ceranae Spores.
Dong Jun KIM ; Hwi Geon YUN ; In Hui KIM ; Won Seok GWAK ; Soo Dong WOO
Mycobiology 2017;45(3):204-208
Nosema ceranae is an obligate intracellular fungal parasite that causes mortality in honey bees and enhances the susceptibility of honey bees to other pathogens. Efficient purification of Nosema spores from the midgut of infected honey bees is very important because Nosema is non-culturable and only seasonably available. To achieve a higher yield of spores from honey bees, in this study, we considered that the initial release of spores from the midgut tissues was the most critical step. The use of 2 mm beads along with enzymatic treatment with collagenase and trypsin enhanced the homogenization of tissues and the yield of released spores by approximately 2.95 times compared with the use of common 3 mm beads alone. The optimal time for the enzyme treatment was determined to be 1 hr as measured by the yield and viability of the spores. A one-step filtration using a filter paper with an 8–11 µm pore size was sufficient for removing cell debris. This method may be useful to purify not only N. ceranae spores but also other Nosema spp. spores.
Bees
;
Collagenases
;
Filtration
;
Honey
;
Methods*
;
Mortality
;
Nosema*
;
Parasites
;
Seasons
;
Spores*
;
Trypsin
7.Entomopathogenic Fungi as Dual Control Agents against Both the Pest Myzus persicae and Phytopathogen Botrytis cinerea.
Hwi Geon YUN ; Dong Jun KIM ; Won Seok GWAK ; Tae Young SHIN ; Soo Dong WOO
Mycobiology 2017;45(3):192-198
The green peach aphid (Myzus persicae), a plant pest, and gray mold disease, caused by Botrytis cinerea, affect vegetables and fruit crops all over the world. To control this aphid and mold, farmers typically rely on the use of chemical insecticides or fungicides. However, intensive use of these chemicals over many years has led to the development of resistance. To overcome this problem, there is a need to develop alternative control methods to suppress populations of this plant pest and pathogen. Recently, potential roles have been demonstrated for entomopathogenic fungi in endophytism, phytopathogen antagonism, plant growth promotion, and rhizosphere colonization. Here, the antifungal activities of selected fungi with high virulence against green peach aphids were tested to explore their potential for the dual control of B. cinerea and M. persicae. Antifungal activities against B. cinerea were evaluated by dual culture assays using both aerial conidia and cultural filtrates of entomopathogenic fungi. Two fungal isolates, Beauveria bassiana SD15 and Metarhizium anisopliae SD3, were identified as having both virulence against aphids and antifungal activity. The virulence of these isolates against aphids was further tested using cultural filtrates, blastospores, and aerial conidia. The most virulence was observed in the simultaneous treatment with blastospores and cultural filtrate. These results suggest that the two fungal isolates selected in this study could be used effectively for the dual control of green peach aphids and gray mold for crop protection.
Aphids*
;
Beauveria
;
Botrytis*
;
Colon
;
Crop Protection
;
Farmers
;
Fruit
;
Fungi*
;
Insecticides
;
Metarhizium
;
Plants
;
Prunus persica
;
Rhizosphere
;
Spores, Fungal
;
Vegetables
;
Virulence
8.A Case of Rapid Progression of Hepatocellular Carcinoma after Radiofrequency Ablation.
Keol LEE ; Dong Hyun SINN ; Geum Youn GWAK ; Yong Han PAIK ; Moon Seok CHOI ; Joon Hyeok LEE ; Kwang Cheol KOH ; Seung Woon PAIK
Journal of Liver Cancer 2015;15(2):118-121
The therapeutic effectiveness and safety of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) have been clinically established, and the procedure is now generally accepted as a curative treatment for very early or early stage HCC. Recently, we observed an aggressive recurrence after RFA for HCC in 50 year-old female. RFA was performed for a 2.7 cm sized HCC, which was completely ablated. However, 7 months later, aggressive intrahepatic recurrence was observed. Herein, we report a case with a discussion.
Ablation Techniques
;
Carcinoma, Hepatocellular*
;
Catheter Ablation*
;
Female
;
Humans
;
Recurrence
9.A Case of Transient Hemolysis Caused by Midazolam.
Hyeri PARK ; Dong Seok GWAK ; Hong Kyun PARK ; Kyeong Joon KIM ; Seong Ho PARK
Journal of the Korean Neurological Association 2011;29(4):404-405
No abstract available.
Epilepsia Partialis Continua
;
Hemolysis
;
Midazolam
10.Retraction: A Case of Rapid Progression of Hepatocellular Carcinoma after Radiofrequency Ablation.
Keol LEE ; Dong Hyun SINN ; Geum Youn GWAK ; Yong Han PAIK ; Moon Seok CHOI ; Joon Hyeok LEE ; Kwang Cheol KOH ; Seung Woon PAIK
Journal of Liver Cancer 2016;16(1):67-67
To preserve scientific integrity, Journal of Liver Cancer agreed with the authors that this paper be retracted.