Acute hemodynamic improvement by thermal vasodilation in congestive heart failure

BACKGROUND

A warm-water bath (WWB) or sauna bath (SB) has generally been considered inappropriate for patients with severe congestive heart failure (CHF). However, a comprehensive investigation of the hemodynamic effects of thermal vasodilation in CHF has not been previously undertaken.

METHODS AND RESULTS

To investigate the acute hemodynamic effects of thermal vasodilation in CHF, we studied 34 patients with chronic CHF (mean age, 58 +/- 14 years). Clinical stages were New York Heart Association functional class II in 2, III in 19, and IV in 13 patients. Mean ejection fraction was 25 +/- 9%. After a Swan-Ganz catheter was inserted via the right jugular vein, the patient had a WWB for 10 minutes at 41 degrees C or an SB for 15 minutes at 60 degrees C. Blood pressure, ECG, echo-Doppler, expiration gas, and intracardiac pressures were recorded before, during, and 30 minutes after each bath. Oxygen consumption increased mildly, pulmonary arterial blood temperature increased by 1.2 degrees C, and heart rate increased by 20 to 25 beats per minute on average at the end of WWB or SB. Systolic blood pressure showed no significant change. Diastolic blood pressure decreased significantly during SB (P < .01). Cardiac and stroke indexes increased and systemic vascular resistances decreased significantly during and after WWB and SB (P < .01). Mean pulmonary artery, mean pulmonary capillary wedge, and mean right atrial pressures increased significantly during WWB (P < .05) but decreased significantly during SB (P < .05). These pressures decreased significantly from the control level after each bath (P < .01). Mitral regurgitation associated with CHF decreased during and 30 minutes after each bath. Cardiac dimensions decreased and left ventricular ejection fraction increased significantly after WWB and SB. In an additional study, plasma norepinephrine increased significantly during SB in healthy control subjects and in patients with CHF and returned to control levels by 30 minutes after SB.

CONCLUSIONS

Hemodynamics improve after WWB or SB in patients with chronic CHF. This is attributable to the reduction in cardiac preload and afterload. Thus, thermal vasodilation can be applied with little risk if appropriately performed and may provide a new nonpharmacological therapy for CHF.

Histopathologic validation of angioscopy and intravascular ultrasound

BACKGROUND

To establish a histopathologic basis for angioscopic and ultrasound image interpretation we studied 70 postmortem human arterial segments in vitro.

METHODS AND RESULTS

We used 7- to 9-French fiber-optic angioscopes and 20- to 30-MHz intravascular ultrasound imaging catheters. Three observers assigned an angioscopic and ultrasound image classification to each vessel segment. The image and histological classification categories were then compared. The sensitivity, specificity, and accuracy of both methods separately or in combination for normal vessels were each greater than or equal to 95%. The predictive value was better for angioscopy than for ultrasound due to incorrect ultrasound interpretations of normal anatomy in the presence of thrombus. For stable atheroma the sensitivity, specificity, and accuracy of the individual methods were each greater than 90%. However, both angioscopy and ultrasound had classification errors in that disrupted atheroma was identified and classified as stable atheroma. Consequently, the predictive value was 74% for angioscopy and 78% for ultrasound. For disrupted atheroma the sensitivities for angioscopy and ultrasound were only moderate (73% and 81%, respectively), whereas the specificity, accuracy, and predictive value were each high (greater than 90%). For thrombus detection, the specificity, accuracy, and predictive value were high (greater than 93%) for each method. The sensitivity of angioscopy was 100%. However, sensitivity was lower for ultrasound (57%) due to false-negative interpretation of laminar clots in normal vessels and an inability to distinguish disrupted or stable atheroma from intraluminal thrombus.

CONCLUSIONS

Contingency analyses showed that each imaging method alone or combined had significant agreement with the results obtained from histology (p less than 0.001). When assessing all cases in which angioscopy and ultrasound were concordant, there was a 92% agreement with the histological classification.

Study on the inhibitory effects of Korean medicinal plants and their main compounds on the 1,1-diphenyl-2-picrylhydrazyl radical

A 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-generating system was used to evaluate the antioxidant properties of Korean medicinal plants that have been used widely as folk medicines for several disorders, as well as compounds isolated from them. Among the Rosaceae, Rosa rugosa and Rosa davurica showed strong DPPH radical-scavenging activity. The most effective medicinal plant from families other than Rosaceae was Cedrela sinensis, followed in order by Nelumbo nucifera, Eucommia ulmoides, Zanthoxylum piperitum, Cudrania tricuspidata and Houttuynia cordata. These results serve as a good index of the free radical-scavenging activities of Korean medicinal plants. Furthermore, the polyphenols isolated from these plants, procyanidin B-3, (+)-catechin, gallic acid, methyl gallate, quercetin, quercetin-3-O-beta-D-glucoside, quercetin-3-O-beta-galactoside, quercetin-3-O-rutinose and kaempferol, exerted strong DPPH radical-scavenging activity. These results suggest that the Korean medicinal plants and the polyphenols isolated from them that exhibited effective radical-scavenging activity may be promising agents for scavenging free radicals and treating diseases associated with excess free radicals.

Antioxidant flavonoids and chlorogenic acid from the leaves of Eriobotrya japonica

The antioxidant activity of Eriobotrya japonica was determined by measuring the radical scavenging effect on DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and lipid peroxidation produced when mouse liver homogenate was exposed to the air at 37 degrees C, using 2-thiobarbituric acid (TBA). The methanol extract and its fractions of Eriobotrya japonica leaves showed strong antioxidant activity. The antioxidant activity of EtOAc and n-BuOH soluble fractions were stronger than the others, and were further purified by repeated silica gel, MCl gel CHP-20P, and Sephadex LH-20 column chromatography. Antioxidant chlorogenic acid, quercetin-3-sambubioside from n-BuOH fraction, and methyl chlorogenate, kaempferol- and quercetin-3-rhamnosides, together with the inactive ursolic acid and 2 alpha-hydroxyursolic acid from EtOAc fraction were isolated. Antioxidant flavonoids and chlorogenic acid also showed prominent inhibitory activity against free radical generation in dichlorofluorescein (DCF) method.

Behavior of osteoblasts on a type I atelocollagen grafted ozone oxidized poly L-lactic acid membrane

With oxidizing poly-L-lactic acid (PLLA) surface by ozone, peroxide groups are easily generated on the surface. Those peroxides are broken down by redox-coupling reaction, and provide active species that initiate grafting by reaction with the collagen molecules. The surface density of generated peroxide on a PLLA surface was determined by an iodide method. The maximum concentration of peroxide was about 2.87 x 10(-8) mol/cm2 when ozone oxidation was performed at 60 V for 60 min. After the surface oxidation, type I atelocollagen was grafted onto PLLA surface. All physical measurements on the collagen-grafted surface indicated that the PLLA surface was effectively grafted with type I atelocollagen. Behavior of rat calvaria osteoblasts on type I atelocollagen grafted PLLA (PLLA + COL) surface was observed. Initial attachment of osteoblasts on the surface was significantly enhanced, and it is assumed that the atelocollagen matrix supported the initial attachment and growth of cells. Collagenous protein synthesis of osteoblasts was maintained at relatively low level in the early stage of proliferation due to the primarily existing grafted type I atelocollagen, and then increased in 7 days as the osteoblast differentiated. After 7 days, collagenous protein synthesis in osteoblasts was activated. Alkaline phosphatase (ALPase) activity and mineralization by osteoblasts were promoted on PLLA + COL surface. In comparison with PLLA + COL, non-treated PLLA and tissue culture plate (TCPS) did not show any feature expressed in osteoblasts' maturation up to 9 days in this experiment. The grafted type I atelocollagen provided a favorable matrix for cell migration in relation with collagenase expression. Ozone oxidation might be a favorable method for surface modification of PLLA membranes by collagen grafting, and cell behavior could be modulated by the grafted collagen.

Panoramic measures for oral bone mass in detecting osteoporosis: a systematic review and meta-analysis

Different quantitative and qualitative indices calculated on oral panoramic radiographs have been proposed as useful tools to screen for reduced skeletal bone mineral density (BMD). Our aim was to systematically review the literature on linear and qualitative panoramic measures and to assess the accuracy of these indices by performing a meta-analysis of their sensitivity and specificity. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Fifty studies were included in the qualitative appraisal and 19 were considered for meta-analysis. The methodological quality of the retrieved studies, assessed with the QUADAS-2 tool, was on average low. Three indices were reported by most of the studies: mandibular cortical width, panoramic mandibular index, and the Klemetti index. Mandibular cortical width presented with a better accuracy in excluding osteopenia/osteoporosis (specificity), since patients with a cortical width more than 4 mm had a normal BMD in 90% of the cases. Almost all studies used a cutoff of 0.3 for the panoramic mandibular index, resulting in an estimated sensitivity and specificity in detecting reduced BMD, respectively, of 0.723 (SE 0.160; 95% confidence interval [CI], 0.352-0.926) and 0.733 (SE 0.066; 95% CI, 0.587-0.841). The presence of any kind of mandibular cortical erosion gave an estimated sensitivity and specificity in detecting reduced BMD, respectively, of 0.789 (SE 0.031; 95% CI, 0.721-0.843) and 0.562 (SE 0.047; 95% CI, 0.47-0.651) and a sensitivity and specificity in detecting osteoporosis, respectively, of 0.806 (SE 0.105; 95% CI, 0.528-0.9200) and 0.643 (SE 0.109; 95% CI, 0.417-0.820). The mandibular cortical width, panoramic mandibular index, and Klemetti index are overall useful tools that potentially could be used by dentists to screen for low BMD. Their limitations are mainly related to the experience/agreement between different operators and the different image quality and magnification of the panoramic radiographs.

Characterization of UV-irradiated dense/porous collagen membranes: morphology, enzymatic degradation, and mechanical properties

Collagen-based membranous materials of various shapes (gel, film, sponge) are known to be the most promising materials in terms of facilitating the regeneration of dermal defects. In this study, dense and porous collagen membranes were fabricated using air-drying and freeze-drying processes, respectively, and the effect of ultraviolet (UV) radiation on the degree of membrane crosslinking was evaluated by in vitro biodegradation and mechanical testing. A non-irradiated membrane group was used as the negative control and a glutaraldehyde (GA) treated group as the positive control. Scanning electron microscopy showed that, as the freezing temperature decreased to -196 degrees C, the resultant mean pore sizes also decreased; optimal pore size was obtained at a freezing temperature of -70 degrees C. In vitro biodegradation and mechanical testing demonstrated that GA treatment or 4 hours of exposure to UV radiation significantly increased both resistance to collagenase and mechanical strength versus the untreated controls, regardless of the collagen membrane type (dense or porous). Our results suggest that UV treatment is a useful tool for the fabrication of collagen membranes designed to be used as dermal dressings.

In vitro validation of three-dimensional intravascular ultrasound for the evaluation of arterial injury after balloon angioplasty

OBJECTIVES

The hypothesis of this study was that three-dimensional ultrasound imaging would facilitate the evaluation of arterial dissection after balloon angioplasty.

BACKGROUND

The presence and extent of arterial dissection occurring at the time of balloon angioplasty may be important predictors of abrupt vessel closure or late restenosis.

METHODS

Forty-one human arterial segments obtained after death were imaged in an in vitro system at physiologic pressure (80 to 100 mm Hg) before and after balloon angioplasty. Images were acquired with a 20- to 30-MHz mechanical intravascular ultrasound imaging system (Cardiovascular Imaging Systems) with a constant pullback technique (1 mm/s). Standard 0.5-in. (1.27-cm) video tapes were used for data storage and later playback for analog to digital conversion. Digitized data were reconstructed to three-dimensional images with use of voxel space modeling. The vessels were opened longitudinally and subjected to pathologic examination, photographed and classified histologically as normal, fibrous or calcified. Dissection was defined as a disruption and separation of components of the arterial wall. The length and depth of arterial dissection were evaluated grossly and microscopically.

RESULTS

Of the 41 arteries studied, 36 (88%) exhibited dissection on pathologic examination after balloon angioplasty. Three-dimensional reconstruction of intravascular ultrasound images identified dissection in 11 (92%) of 12 normal, 8 (100%) of 8 fibrous and 11 (69%) of 16 calcified arteries. Excellent agreement between ultrasound and pathologic findings was achieved in the evaluation of length and depth of dissection for histologically normal and fibrous arteries (kappa = 0.72 to 1.0). When the vessels were severely calcified, the agreement was not as good (kappa = 0.27 to 0.56), particularly in detection of small, non-raised intimal flaps.

CONCLUSIONS

This histopathologic validation study suggests that three-dimensional intravascular ultrasound imaging facilitates the evaluation of both quantitative and morphologic features of arterial dissection induced by balloon angioplasty. The advantage of three-dimensional intravascular ultrasound is its ability to assess the length and morphology of arterial injury over an entire vessel segment.

Histologic diagnosis based on forceps biopsy is not adequate for determining endoscopic treatment of gastric adenomatous lesions

BACKGROUND AND STUDY AIMS

Controversy persists around the treatment of gastric low-grade dysplasia (LGD). The aim of this study was to investigate possible indications for the endoscopic resection of gastric LGD through analysis of the histologic discrepancies between specimens of gastric LGD obtained by forceps biopsy and by endoscopic mucosal resection (EMR), and of their clinicopathologic characteristics.

PATIENTS AND METHODS

The study involved 293 gastric LGD that were histologically proven on the basis of forceps biopsy in Severance Hospital between January 2004 and December 2007. Twenty cases were regularly followed up, and the remaining 273 were resected by EMR. We performed univariate and multivariate analyses of clinical and endoscopic characteristics including lesion size, number of biopsy fragments, and endoscopic appearance, in order to analyze the factors affecting histologic discrepancies.

RESULTS

Of the 273 lesions resected by EMR, 207 (75.8 %) showed concordant histology, whereas for 51 (18.7 %) the histology was upgraded after endoscopic resection. Lesion size, absence of whitish discoloration, and the presence of spontaneous bleeding were found by univariate analysis to be statistically significant factors predicting an upgraded histology after EMR ( P = 0.026, P < 0.001, and P = 0.025, respectively). Multivariate analysis also showed absence of whitish discoloration to be a statistically significant factor influencing histologic discrepancies ( P = 0.001, odds ratio 5.29, 95 % confidence interval 1.95 - 14.37). Perforation and bleeding rates associated with EMR for LGD were 0.7 % and 6.2 %, respectively. Twenty patients who did not undergo EMR were followed up for a mean of 22 months, and 3 were revealed to have adenocarcinoma and 1 high-grade dysplasia on the latest histologic exam.

CONCLUSIONS

We should consider endoscopic resection for gastric LGD that are 2 cm or more in size and do not have whitish discoloration.

Bench-top Comparison of Physical Properties of 4 Commercially-Available Self-Expanding Intracranial Stents

PURPOSE

To better understand the performance of four commercially available neurovascular stents in intracranial aneurysm embolization, the stents were compared in terms of their basic morphological and mechanical properties.

MATERIALS AND METHODS

Four different types of stents that are currently being used for cerebral aneurysm embolization were prepared (two stents per type). Two were laser-cut stents (Neuroform and Enterprise) and two were braided from a single nitinol wire (LEO and LVIS stents). All were subjected to quantitative measurements of stent size, pore density, metal coverage, the force needed to load, push, and deploy the stent, radial force on deployment, surface roughness, and corrosion resistance.

RESULTS

Compared to their nominal diameters, all stents had greater diameters after deployment. The length generally decreased after deployment. This was particularly marked in the braided stents. The braided stents also had higher pore densities than the laser-cut stents. Metal coverage was highest in the LEO stent (14%) and lowest in the Enterprise stent (5%). The LIVS stent had the highest microcatheter loading force (81.5 gf). The LEO stent had the highest passage force (55.0 gf) and deployment force (78.9 gf). The LVIS and LEO stents had the highest perpendicular (37.1 gf) and circumferential (178.4 gf) radial forces, respectively. The Enterprise stent had the roughest stent wire, followed by the LVIS, LEO, and Neuroform stents.

CONCLUSION

The four neurovascular stent types differed in terms of morphological and physical characteristics. An understanding of this diversity may help to decide which stent is most suitable for specific clinical situations.

The prevalence of trimethoprim-resistance-conferring dihydrofolate reductase genes in urinary isolates of Escherichia coli in Korea

One-hundred and twenty-two urinary isolates of Escherichia coli were studied for trimethoprim resistance. Seventy-seven (63.1%) of the 122 isolates were found to be resistant to trimethoprim. Of the 77 trimethoprim-resistant isolates, 75 dfr genes were detected in 72 isolates as follows: the dfrA17 gene was the most prevalent, being found in 27 isolates, followed by dfrA12 in 26, dfrA1 in 15, dfrA5 in four and dfrA7 in three. Southern blot and PCR mapping analysis revealed that all of the dfrA17, dfrA12, dfrA5 and dfrA7 genes were located on class 1 integrons. The dfrA1 gene inserted as a gene cassette in class 1 integrons was found in 10 of 15 isolates, and the intI2 gene of Tn7 was detected in two out of five isolates. In conjugation experiments, the dfr genes inserted in class 1 integrons were transferred to a recipient E. coli in 32 (42.7%) of the 75 dfr genes. In conclusion, the dfrA17 and dfrA12 genes were the most prevalent genes responsible for trimethoprim resistance in urinary tract isolates of E. coli from Korea and the dfr genes inserted in integrons are more widespread than those that are not related to gene cassettes.

Preventive effects of the heparin-coated stent on restenosis in the porcine model

The coronary stent reduces acute coronary arterial occlusion and late restenosis during and after coronary intervention. However, stent thrombosis and restenosis are still major limitations in the widespread use of the coronary stent. Local drug delivery using the heparin-coated stent may be a new approach, which reduces the incidence of stent thrombosis and restenosis. In order to evaluate the effects of the heparin-coated stent on stent restenosis, heparin-coated stents were compared with control stents in a porcine coronary stent restenosis model. Stent overdilation injury (stent:artery = 1.3:1.0) was performed with bare Wiktor stents (group I, n = 10) and heparin-coated Wiktor stents (group II, n = 20; HEPAMED, Medtronics) in porcine coronary arteries. Follow-up quantitative coronary angiography (QCA) was performed at 4 weeks after stenting, and histo-pathologic assessments of stented porcine coronary arteries were compared in both groups. On QCA, percent diameter stenosis was significantly higher in group I than in group II (16.3% +/- 6.62% vs. 9.6% +/- 5.06%, P < 0.05). The injury score of stented porcine coronary arteries was the same in both groups (1. 26 +/- 0.23 vs. 1.20 +/- 0.22). The area of pathologic stenosis of the stented arteries was higher in group I than in group II (41.6% +/- 12.5% vs. 27.1% +/- 9.9%, P < 0.005). The neointimal area was higher in group I than in group II (4.58 +/- 1.41 mm(2) vs. 2.57 +/- 1.07 mm(2), P < 0.05). By immunohistochemistry, the proliferating cell nuclear antigen (PCNA) index was higher in group I compared with group II (11.2% +/- 6.75% vs. 6.3% +/- 4.14%, P < 0.05). The heparin-coated stent is effective in the prevention of late coronary stent restenosis in a porcine coronary stent restenosis model. This may be related to the inhibition of neointimal cell proliferation.

Shaping and Navigating Methods of Microcatheters for Endovascular Treatment of Paraclinoid Aneurysms

OBJECTIVE

To determine whether the use of a specific shape and a navigating method of microcatheters are suitable for placement at paraclinoid aneurysms.

METHODS

The clinical data from 122 patients with 132 paraclinoid aneurysms that underwent endovascular treatments during a 2.5-year period were retrospectively reviewed. Microcatheter shapes were classified as “straight,” “primary curves” (45, 90, and J), “preshaped-C,” “pigtail” (simple, right, and left), and “S” (simple, right, left, and preshaped). The navigating methods were classified as antegrade/retrograde microcatheter shift, wire-steering, looping, and coil/wire guiding. The shapes and navigating methods were compared among 3 aneurysm groups, which were categorized as superior, medial, and other, based on direction.

RESULTS

Shapes were significantly different between the 3 groups; the most commonly engaged shape in the superior group, medial group, and other group was S (55%), pigtail (60%), and primary (56%), respectively. The straight and S shapes were used in 5 (83%) and 18 (86%) cases, respectively, in the superior group, whereas the pigtail shape was used in 50 (86%) cases in the medial group. Aside from pigtail-simple shape, the side of pigtail, right vs left, coincided with the side of the internal carotid artery involved in every case of the medial group. The navigating methods were not significantly different among the 3 groups.

CONCLUSION

A specific shape by paraclinoid aneurysm direction tends to be suitable for the first trial of microcatheter shapes. Operators may reduce unnecessary struggling time of intra-aneurysmal placement of microcatheters by practicing the use of that shape.

Protective effects of green tea polyphenol against reactive oxygen species-induced oxidative stress in cultured rat calvarial osteoblast

The injurious effects of reactive oxygen species on osteoblasts and the potential protective role played by green tea polyphenols (GtPP) were investigated using primarily cultured rat calvarial osteoblasts. Oxidative stress was induced in cultured osteoblasts, either by adding 100 mmol/L H2O2 or by the action of 40 U/L xanthine oxidase (XO) in the presence of xanthine (250 micromol/L). After incubation, the cellular viability, function and morphology were evaluated. Both treatments produced a significant reduction in osteoblast viability, as assessed by a two-colored fluorescence staining method combined with flow cytometric analysis and MTT assay. A significant reduction in the alkaline phosphatase activity was observed after H2O2 addition, whereas XO did not have the same effect. On the microscopic observations, the morphological changes and intracellular ultrastructural damages were remarkably induced by both treatments. The H2O2-induced alterations were prevented by pre-incubating the osteoblasts with 200 microg/ml GtPP for 1 h. When the oxidative stress was induced by XO, the cellular viability and morphology was also maintained at the same polyphenol concentration. These results demonstrate that GtPP can act as a biological antioxidant in a cell culture experimental model and protect cells from oxidative stress-induced toxicity.

Genetic driver mutations define the expression signature and microenvironmental composition of high-grade gliomas

High-grade gliomas (HGG), including glioblastomas, are characterized by invasive growth, resistance to therapy, and high inter- and intra-tumoral heterogeneity. The key histological hallmarks of glioblastoma are pseudopalisading necrosis and microvascular proliferation, which allow pathologists to distinguish glioblastoma from lower-grade gliomas. In addition to being genetically and molecularly heterogeneous, HGG are also heterogeneous with respect to the composition of their microenvironment. The question of whether this microenvironmental heterogeneity is driven by the molecular identity of the tumor remains controversial. However, this question is of utmost importance since microenvironmental, non-neoplastic cells are key components of the most radiotherapy- and chemotherapy-resistant niches of the tumor. Our work demonstrates a versatile, reliable, and reproducible adult HGG mouse model with NF1-silencing as a driver mutation. This model shows significant differences in tumor microenvironment, expression of subtype-specific markers, and response to standard therapy when compared to our established PDGFB-overexpressing HGG mouse model. PDGFB-overexpressing and NF1-silenced murine tumors closely cluster with human proneural and mesenchymal subtypes, as well as PDGFRA-amplified and NF1-deleted/mutant human tumors, respectively, at both the RNA and protein expression levels. These models can be generated in fully immunocompetent mixed or C57BL/6 genetic background mice, and therefore can easily be incorporated into preclinical studies for cancer cell-specific or immune cell-targeting drug discovery studies.

Morphometric analysis and fine structure of the vestibular epithelium of aged C57BL/6NNia mice

The vestibular organs of young and very old C57BL/6NNia (B6) mice were compared by light and electron microscopy. Hair cell density decreased an average of 14% in the utricle, 19% in the saccule and posterior crista, 23% in the horizontal crista, and 24% in the anterior crista. Hair cell size remained the same throughout the mouse's life span as did the ratio of Type I to Type II hair cells. The most apparent sign of advanced age was dense inclusions found in sensory and supporting cells. Although small inclusions were present at five weeks, by 29 months, additional, larger forms appeared. An unusual melanin-like form was characteristic of old Type I hair cells. Synaptic morphology and synaptic bodies were well preserved even in very old B6 mice. Elongated bars were common in Type I hair cells and spheroid synaptic bodies were the most common form in Type II hair cells. Large clusters of synaptic bodies occurring in both young and old mice were seen only in Type I hair cells. Although the B6 strain suffers from genetically determined early cochlear degeneration, it does not experience early degeneration of the peripheral vestibular organs.

Korean Clinical Practice Guidelines for Aneurysmal Subarachnoid Hemorrhage

Despite advancements in treating ruptured cerebral aneurysms, an aneurysmal subarachnoid hemorrhage (aSAH) is still a grave cerebrovascular disease associated with a high rate of morbidity and mortality. Based on the literature published to date, worldwide academic and governmental committees have developed clinical practice guidelines (CPGs) to propose standards for disease management in order to achieve the best treatment outcomes for aSAHs. In 2013, the Korean Society of Cerebrovascular Surgeons issued a Korean version of the CPGs for aSAHs. The group researched all articles and major foreign CPGs published in English until December 2015 using several search engines. Based on these articles, levels of evidence and grades of recommendations were determined by our society as well as by other related Quality Control Committees from neurointervention, neurology and rehabilitation medicine. The Korean version of the CPGs for aSAHs includes risk factors, diagnosis, initial management, medical and surgical management to prevent rebleeding, management of delayed cerebral ischemia and vasospasm, treatment of hydrocephalus, treatment of medical complications and early rehabilitation. The CPGs are not the absolute standard but are the present reference as the evidence is still incomplete, each environment of clinical practice is different, and there is a high probability of variation in the current recommendations. The CPGs will be useful in the fields of clinical practice and research.

Vestibular ototoxicity in the chick: effects of streptomycin on equilibrium and on ampullary dark cells

Starting a week after they were hatched, chicks received daily subcutaneous injections of streptomycin sulfate for 15 or 30 days at one of three dosages: 400, 800, or 1,200 mg/kg body weight. During the period of administration, the chicks were weighed, examined for signs of systemic intoxication, and tested for impairment of equilibrium. At intervals some birds from each group were sacrificed and the end-organs of the semicircular canals were examined for damage. After the fifteenth injection, the weights of the control and experimental chicks were similar. By comparison, the chicks that received streptomycin injections showed varying degrees of impairment of equilibrium. First, some birds in the three experimental groups began to tremble at least slightly by the third injections, but others, particularly at the highest dosage (1,200 mg/kg body weight), trembled severely by the fifth injections. However, trembling began to subside in the lowest-dosage (400 mg/kg body weight) group by the fourteenth injection. Second, the chicks' ability to perch on dowels, either hooded or unhooded, and their ability to perch on the investigator's fingers in the dark deteriorated. Perching performances on the dowel deteriorated conspicuously only at higher dosages, while changes in perching on the finger were detected earlier and at lower dosages. Streptomycin damaged dark cells before other cell types. The cuboidal dark cells were most sensitive, followed by the pyriform cells. The eminential cells were least sensitive. Although the hair cells were functionally damaged by either the primary or the secondary actions of streptomycin, as evidenced by the chicks' early impairment of equilibrium, they showed distinct cytologic lesions later than did the dark cells.

Type I atelocollagen grafting onto ozone-treated polyurethane films: cell attachment, proliferation, and collagen synthesis

An approach is presented for the graft copolymerization of type I atelocollagen onto the surface of polyurethane (PU) films treated with ozone. Through inducing oxidization to modify PU surface by ozone, peroxide groups are easily generated on the surface. Those peroxides are broken by redox-polymerization, and provide active species which initiate graft polymerization by reacting with amines in the collagen molecules. The ozone oxidation time and voltage could readily control the amount of peroxide production. The surface density of generated peroxides on PU surface was determined by iodide method. The maximum concentration of peroxide was about 10.20 x 10(-8)mol/cm(2) when ozone oxidation was performed at 60 V for 30 min. After the reaction of PU by ozone oxidation, type I atelocollagen was graft-copolymerized onto the PU film. All the physical measurements on the collagen-grafted surface indicated that the PU surface was effectively covered with type I atelocollagen. The interaction of the collagen-grafted PU surface with fibroblasts could be greatly enhanced by the surface graft polymerization with type I atelocollagen. Attachment and proliferation of fibroblasts on the grafted type I atelocollagen were significantly enhanced, and it is assumed that the atelocollagen matrix supported the initial attachment and growth of cells. In the early stage of proliferation, collagen synthesis in fibroblasts was not activated and remained at a relatively low level due to the grafted type I atelocollagen, increasing only with fibroblast differentiation.

Iatrogenic spinal epidermoid tumor. A complication of spinal puncture in an adult

A case of an intraspinal epidermoid tumor following a lumbar puncture (LP) is described. This tumor developed 5 years after a LP in a man aged 31 years. The majority of epidermoid tumors reported are late complications of spinal puncture during the early neonatal period. To the best of our knowledge, this case is the third oldest patient, whose symptoms presented relatively early after the initial LP. He was successfully treated by surgery. Pathologic diagnosis revealed an epidermoid cyst. The relation between LP and epidermoid tumor and the possible risk factors involved are discussed.

Socioeconomic disparities of periodontitis in Koreans based on the KNHANES IV

OBJECTIVES

The aim of this study was to identify the socioeconomic factors associated with the prevalence of periodontitis in Koreans.

METHODS

Cross-sectional data from 12 763 subjects, 15 years old and above, who underwent periodontal examinations were obtained from the Korean National Health and Nutrition Examination Survey IV (2007-209). Multivariate linear and logistic regression analyses were applied to estimate the association between socioeconomic indicators and prevalence of periodontitis.

RESULTS

A significant association was found between increasing age and periodontitis. Participants with higher income were less likely to have periodontitis (aOR = 0.9 and 95% CI = 0.78-0.98, and aOR = 0.7 and 95% CI = 0.60-0.80 in the middle and highest quintiles of monthly household income, respectively). In addition, participants living in rural areas were less likely to have periodontitis (aOR = 0.9 and 95% CI = 0.81-0.99), and current smokers were more likely to have periodontitis (aOR = 1.7 and 95% CI = 1.49-1.89). The analysis of comorbidities revealed that individuals with diabetes mellitus (DM) were significantly more likely to have periodontitis (aOR = 1.4 and 95% CI = 1.18-1.68).

CONCLUSIONS

In a rapidly increasing Korean population, the lower socioeconomic groups as well as individuals with DM were significantly more likely to present with periodontitis.

Microembolism after endovascular coiling of unruptured cerebral aneurysms: incidence and risk factors

OBJECTIVE

The incidence and risk factors of microembolic lesions on MR diffusion-weighted imaging (DWI) were analyzed after the endovascular coiling of unruptured intracranial aneurysms (UIAs).

METHODS

Data obtained from 271 consecutive patients (70 men and 201 women; median age 57 years; range 23-79 years) who presented with UIA for coil embolization between July 2011 and June 2013 were analyzed. Two independent reviewers examined the DWI and apparent diffusion coefficient maps obtained the following day for the presence of restrictive diffusion spots and counted the number of spots. Multivariate analysis was then performed to identify independent risk factors for developing microembolism following the coiling of an aneurysm.

RESULTS

Microembolic lesions were noted in 101 of 271 patients (37.3%). The results of the multivariate analysis showed that the following factors significantly influenced the risk for microembolism: age, diabetes, previous history of ischemic stroke, high-signal FLAIR lesions in the white matter, multiple aneurysms, and the insertion of an Enterprise stent (all ORs > 1.0 and all p values < 0.05). Previously known risk factors such as prolonged procedure duration, aneurysm size, and decreased antiplatelet function did not show any significant influence.

CONCLUSIONS

The incidence of microembolism after endovascular coiling of UIA was not low. Lesions occurred more frequently in patients with vascular status associated with old age, diabetes, and previous stroke. Aneurysm multiplicity and the type of stent used for treatment also influenced lesion occurrence.

Pipeline Embolization Device for Large/Giant or Fusiform Aneurysms: An Initial Multi-Center Experience in Korea

Purpose

The purpose of this study was to assess the safety and early outcomes of the Pipeline device for large/giant or fusiform aneurysms.

Materials and Methods

The Pipeline was implanted in a total of 45 patients (mean age, 58 years; M:F=10:35) with 47 large/giant or fusiform aneurysms. We retrospectively evaluated the characteristics of the treated aneurysms, the periprocedural events, morbidity and mortality, and the early outcomes after Pipeline implantation.

Results

The aneurysms were located in the internal carotid artery (ICA) cavernous segment (n=25), ICA intradural segment (n=11), vertebrobasilar trunk (n=8), and middle cerebral artery (n=3). Procedure-related events occurred in 18 cases, consisting of incomplete expansion (n=8), shortening-migration (n=5), transient occlusion of a jailed branch (n=3), and in-stent thrombosis (n=2). Treatment-related morbidity occurred in two patients, but without mortality. Both patients had modified Rankin scale (mRS) scores of 2, but had an improved mRS score of 0 at 1-month follow-up. Of the 19 patients presenting with mass effect, 16 improved but three showed no changes in their presenting symptoms. All patients had excellent outcomes (mRS, 0 or 1) during the follow-up period (median, 6 months; range, 2-30 months). Vascular imaging follow-up (n=31, 65.9%; median, 3 months, range, 1-25 months) showed complete or near occlusion of the aneurysm in 24 patients (77.4%) and decreased sac size in seven patients (22.6%).

Conclusion

In this initial multicenter study in Korea, the Pipeline seemed to be safe and effective for large/giant or fusiform aneurysms. However, a learning period may be required to alleviate device-related events.

Occipital artery-posterior inferior cerebellar artery bypass for the treatment of aneurysms arising from the vertebral artery and its branches

OBJECTIVE

To report experience with 7 cases of intracranial aneurysms of the vertebral artery (VA) and its branches that were treated with occipital artery (OA)-posterior inferior cerebellar artery (PICA) bypass.

METHODS

Over 4 years, 7 cases of intracranial aneurysms arising from the VA and its branches were treated with OA-PICA bypass. The clinical data, characteristics of aneurysms, and results of treatment were analyzed.

RESULTS

There were 4 aneurysms that arose from the VA-PICA junction, 2 aneurysms that occurred at the distal PICA, and 1 aneurysm that occurred at the collateral artery from the distal end of the occluded VA to the ipsilateral PICA. OA-PICA bypass was performed before obliteration of the aneurysms in all patients. Of the 7 aneurysms, 4 were totally obliterated with surgery, 2 were treated with additional endovascular coiling or trapping, and 1 was partially obliterated by surgery and gradually disappeared during the follow-up period. Postoperative angiography revealed that the patency of the grafts was good in 6 patients. In 1 patient with an occluded bypass graft, multiple infarctions developed in the left cerebellum, but the patient had almost fully recovered after rehabilitation.

CONCLUSIONS

OA-PICA bypass with obliteration of the aneurysm is one of the optimal treatments for intracranial aneurysms that occur at the VA and its branches because it can preserve the perforators and distal blood flow from the PICA.