Vancomycin-lnduced fluorescence and morphological changes in bis(dipeptide)-containing biphenyl supramolecules

A biphenyl derivative containing two D-Ala-D-Ala moieties was found to form fluorescent nano/microfibers when subjected to self-assembly conditions in aqueous EtOH. Incubation of the nano/microfibers with vancomycin results in the disappearance of the fibers along with a significant decrease in the fluorescence intensity. The detection limit of vancomycin determined by the fluorescence quenching strategy was calculated to be ca. 57 μM. Regeneration of the original fiber structures were obtained in the presence of Ac-Lys(Ac)-D-Ala-D-Ala, a substance known to bind tightly to vancomycin. Other proteins including bovine serum albumin (BSA), casein, elastase, and chymotrypsin were found to cause no morphological and fluorescence changes in the supramolecules. The unique vancomycin-induced phase transition and fluorescence change were not observed with a biphenyl derivative having L-Ala-L-Ala moiety.

Clinical practice guidelines for the medical and surgical management of primary intracerebral hemorrhage in Korea

The purpose of this clinical practice guideline (CPG) is to provide current and comprehensive recommendations for the medical and surgical management of primary intracerebral hemorrhage (ICH). Since the release of the first Korean CPGs for stroke, evidence has been accumulated in the management of ICH, such as intracranial pressure control and minimally invasive surgery, and it needs to be reflected in the updated version. The Quality Control Committee at the Korean Society of cerebrovascular Surgeons and the Writing Group at the Clinical Research Center for Stroke (CRCS) systematically reviewed relevant literature and major published guidelines between June 2007 and June 2013. Based on the published evidence, recommendations were synthesized, and the level of evidence and the grade of the recommendation were determined using the methods adapted from CRCS. A draft guideline was scrutinized by expert peer reviewers and also discussed at an expert consensus meeting until final agreement was achieved. CPGs based on scientific evidence are presented for the medical and surgical management of patients presenting with primary ICH. This CPG describes the current pertinent recommendations and suggests Korean recommendations for the medical and surgical management of a patient with primary ICH.

Endovascular coil embolization after clipping: endovascular treatment of incompletely clipped or recurred cerebral aneurysms

OBJECTIVE

The presence of a cerebral aneurysm remnant after surgical clipping is associated with a risk of regrowth or rupture. For these recurred aneurysms, coil embolization can be considered as a treatment option. We retrospectively reviewed cases of ruptured or regrown aneurysms after clipping treated by endovascular coil embolization.

MATERIALS AND METHODS

We conducted a retrospective review of patients with ruptured or recurred aneurysm after clipping, who underwent coil embolization between January 1995 and December 2013. We evaluated clinical information and the outcomes of these cases.

RESULTS

Eight patients were treated by endovascular coil embolization after surgical clipping. Six aneurysms were located in the anterior communicating artery, one in the posterior communicating artery, and one in the middle cerebral artery bifurcation. All patients were initially treated by surgical clipping because of a ruptured aneurysm. Aneurysm recurrence at the initial clipping site was detected in all cases. The median interval from initial to second presentation was 42 months. In four patients, aneurysms were detected before rupture and the four remaining patients presented with recurrent subarachnoid hemorrhage. All patients were treated by coil embolization and showed successful occlusion of aneurysms without complications.

CONCLUSION

Endovascular coil embolization can be a safe and successful treatment option for recurred aneurysms after clipping.

Acute spontaneous spinal subdural hematoma with vague symptoms

Spinal subdural hematoma is a rarely reported disease and spontaneous spinal subdural hematomas (SSDH) without underlying pathological changes are even rarer. The patients usually show typical symtoms such as back pain, quadriplegia, paraplegia or sensory change. But rarely, patients may show atypical symptoms such as hemiparesis and misdiagnosed to cerebrovascular accident. We recently experienced a case of SSDH, where the patient initially showed vague symptoms, such as the sudden onset of headache which we initially misdiagnosed as subarachnoid hemorrhage. In this case, the headache of patient improved but the neck pain persisted until hospital day 5. Therefre, we conducted the MRI of cervical spine and finally confirmed SSDH. The patient was managed conservatively and improved without recurrence. In this case report, we discuss the clinical features of SSDH with emphasis on the importance of an early diagnosis.

Densely packed siloxane barrier for blocking electron recombination in dye-sensitized solar cells

A challenge in developing photovoltaic devices is to minimize the loss of electrons, which can seriously deteriorate energy conversion efficiency. In particular, minimizing this negative process in dye-sensitized solar cells (DSCs) is imperative. Herein, we use three different kinds of siloxanes, which are adsorbable to titania surfaces and polymerizable in forming a surface passivation layer, to reduce the electron loss. The siloxanes used are tetraethyl orthosilicate (TEOS or compound A), 1-(3-(1H-imidazol-1-yl)propyl)-3-(3-triethoxysilyl) propyl) urea (compound B), and N-(3-triethoxysilylpropyl)-N'[3-(3-methyl-1H-imidazol-3-ium) propyl] urea iodide (compound C). Titania surface passivation by either compound B or C was comparatively more effective in increasing the electron lifetime than TEOS. In the case of small-sized TEOS combined with either large-sized compound B or C, a thinner and denser passivation layer was presumably developed, thus increasing electron lifetime further. Intriguingly, device AB shows the longest electron lifetime, whereas device AC has the highest energy conversion efficiency among these experimental conditions. These results suggest that, in this special case, the electron lifetime may not be a dominant parameter in determining the energy conversion efficiency.

An electrothermochromic paper display based on colorimetrically reversible polydiacetylenes

An electrothermochromic paper display composed of colorimetrically reversible polydiacetylenes (PDAs), utilizing screen printing on photopaper and patterning of electrically conductive wires on the reverse side, was developed. Heat generated by passing a current through the wires on the back of the photopaper induced a blue-to-red color transition of the PDA on the front at regions corresponding to the wires. This resulted in the generation of red-colored images, which disappeared when the supplied electric current was removed. The voltage at which the PDAs changed color could be controlled by using structured diacetylene (DA) monomers. A PDA-based seven-segment display has also been developed. By applying voltages, red-colored numeric digits from 0 to 9 can be displayed on the surface of the PDA layer.

Clinical and angiographic features and stroke types in adult moyamoya disease

BACKGROUND AND PURPOSE

This study was conducted to elucidate the association between clinical and angiographic characteristics and stroke types in adult Moyamoya disease that has been rarely evaluated.

MATERIALS AND METHODS

We analyzed the clinical and radiologic data obtained from a retrospective adult Moyamoya disease cohort with acute strokes, which were classified into 7 categories: large-artery infarct, hemodynamic infarct, perforator infarct, deep intracerebral hemorrhage, lobar intracerebral hemorrhage, intraventricular hemorrhage, and SAH. With conventional angiography, which was performed in the hemispheres with acute strokes, the Suzuki angiographic stage, intracranial aneurysm, major artery occlusion, and collateral vessel development were confirmed within 1 month of stroke onset.

RESULTS

This study included 79 patients with acute ischemic stroke and 96 patients with acute hemorrhagic stroke. The angiographic stage had a strong tendency to be more advanced in the hemorrhagic than the ischemic patients (P = .061). Intracranial aneurysms were more frequently found in the hemorrhagic than ischemic or control hemispheres (P = .002). Occlusions of the anterior cerebral artery and development of fetal-type posterior cerebral artery were more frequently observed in the hemorrhagic than the ischemic (P = .001 and .01, respectively) or control hemispheres (P = .011 and .013, respectively). MCA occlusion (P = .039) and collateral flow development, including the ethmoidal Moyamoya vessels (P = .036) and transdural anastomosis of the external carotid artery (P = .022), occurred more often in the hemorrhagic than the ischemic hemispheres. Anterior cerebral artery occlusion occurred more frequently in patients with deep intracerebral hemorrhage or intraventricular hemorrhage than with lobar intracerebral hemorrhage (P = .009).

CONCLUSIONS

In adult Moyamoya disease, major artery occlusion and collateral compensation occurred more often in the hemorrhagic than in the ischemic hemispheres. Thus, anterior cerebral artery occlusion with or without MCA occlusion and intracranial aneurysms may be the main contributing factors to hemorrhagic stroke in adult patients with Moyamoya disease.

Photochromic spiropyran-embedded PDMS for highly sensitive and tunable optochemical gas sensing

A highly sensitive, tunable, flexible and microfluidic compatible gas sensor was developed based on a photochromic spiropyran-embedded PDMS composite.

Tophaceous gout of the spine causing neural compression

Gout is a common metabolic disease in which monosodium urate crystals called tophi develop. Spinal involvement in gout resulting in neural compression is unusual. We describe a case of a 64-year-old man with a history of gouty arthritis of the knee. The patient presented with thoracic myelopathy and radiculopathy. Imaging of the spine revealed an extradural mass lesion with bony erosion of the thoracic spine. A decompressive operation was performed, and a chalky white material was found. Histopathological examination confirmed a gouty tophus. The symptoms of spinal gout vary and its radiological features are not sufficiently specific to provide a definite diagnosis. Therefore, in patients with a history of gouty arthritis who present with neural compressive symptoms of the spine, spinal gout should be strongly suspected.

Rotational Vertebral Artery Compression : Bow Hunter's Syndrome

Bow hunter's syndrome (BHS) is rare cause of vertebrobasilar insufficiency that arises from mechanical compression of the vertebral artery by head rotation. There is no standardized diagnostic regimen or treatment of BHS. Recently, we experienced 2 cases resisted continues medication and treated by surgical approach. In both cases, there were no complications after surgery and there were improvements in clinical symptoms. Thus, we describe our cases with surgical decompression with a review of the relevant medical literature.

The outcomes of spontaneous intracerebral hemorrhage in young adults - a clinical study

Objective

Spontaneous intracerebral hemorrhage (ICH) in young adults is rare. The purpose of this study was to investigate causes, sites and other factors affecting the prognosis of ICH in young adults aged ≤ 40 years.

Methods

We reviewed 39 consecutive patients diagnosed with spontaneous ICH between January 2001 and June 2012. Patients with primary subarachnoid hemorrhage, previously diagnosed brain tumor bleeding, or vascular malformation were excluded. We analyzed the differences in prognostic factors such as hemorrhage location and vascular structural etiology. The outcome was measured using the Glasgow outcome scale (GOS), and a good outcome was defined as a score of 4 or more.

Results

We retrospectively evaluated 39 patients (mean age, 33 years; SD = 6.4, range 17 to 40 years). The most common structural etiology was arteriovenous malformation. A statistically significantly higher proportion of patients with good outcomes had a lower initial systolic blood pressure (SBP ≤ 160 mmHg, p = 0.036), a higher initial Glasgow coma scale (GCS) (9 or more, p = 0.034), lower cholesterol levels (< 200 mg/dl, p = 0.036), and smoking history (at discharge, p = 0.008; 6 months after discharge, p = 0.019).

Conclusion

In this study, cryptogenic ICH was the leading cause of spontaneous ICH. A GCS score of 9 or more on admission, a lower serum cholesterol level (< 200 mg/dl), and a lower SBP (< 160 mmHg) predicted a good outcome.

A soluble, low-temperature thermochromic and chemically reactive polydiacetylene

The majority of polydiacetylenes (PDAs) described to date display thermochromic transitions above room temperature. By following a strategy that employs headgroups that do not participate in strong interactions, we have designed and prepared a liquid diacetylene (DA) monomer that solidifies at a temperature near 0 °C. The isocyanate-containing DA monomer, DA-NCO, having this property does not undergo polymerization in its liquid state at room temperature. However, UV irradiation of frozen DA-NCO at 0 °C causes the instantaneous formation of a blue PDA (PDA-NCO). Interestingly, PDA-NCO was found to display a sharp blue-to-red color transition at a temperature near 11 °C. By taking advantage of its room temperature liquid-phase property, we were able to readily transfer the DA monomer to solid substrates by using common stamping and writing methods used for creating patterned PDA images. In addition, PDA-NCO dissolves in chloroform, giving a yellow solution that becomes red and simultaneously generates polymer aggregates when hexane is added. Finally, the isocyanate moieties present in PDA-NCO have been utilized to differentiate 1° from 2° and 3° amines owing to the fact that a chloroform solution of PDA-NCO undergoes a rapid yellow-to-red color change associated with an insoluble urea-forming reaction with primary amines.

Effects of task constraints on obstacle avoidance strategies in patients with cerebellar disease

The present study examined the effects of cerebellar disease on the organization and execution of obstacle avoidance tasks. To this end, we characterized how variations in the execution demands of the subsequent obstacles in multiple obstacle crossing tasks influenced the stepping performance of the initial obstacle in patients with cerebellar degeneration (CD) by manipulating the height (6 cm and 16 cm) and distance (1 m and 2 m) of the second obstacle. Nine patients with bilateral cerebellar atrophy and nine age-matched normal controls were instructed to walk along an 8 m long pathway and step over two obstacles without contacting them. The primary finding indicated that CD patients exhibited an elevated foot clearance over the initial obstacle when the height demand of the second obstacle was increased. Such abnormal step-height adjustments in CD patients are considered as an adaptive avoidance strategy to diminish the execution demands of complex obstacle tasks and to enhance safe performance. These results suggest that the cerebellum is important for the implementation of optimal stepping strategies to be used during multiple obstacle crossings in which the obstacles have different execution demands.

The correlation between expression of synuclein-gamma, glucose transporter-1, and survival outcomes in endometrioid endometrial carcinoma

PURPOSE

To evaluate the correlation between immunohistochemical expression of synuclein-gamma, glucose transporter-1, and survival outcomes in endometrioid endometrial carcinoma.

MATERIALS AND METHODS

A tissue microarray was constructed using formalinfixed, paraffin-embedded tissue that included 23 early and 18 advanced cases. The intensity and area of the immunohistochemical reactions were evaluated using the semi-quantitative scoring system.

RESULTS

Synuclein-y expression was higher in the advanced stage, although it was not statistically significant (p = 0.51). Glucose transporter-1 was overexpressed in the advanced stage (p = 0.01). Synuclein-gamma (score = 0 vs > 0) and glucose transporter-1 (score < or = 7 vs > 7) did not show any differences in overall survival (p = 0.54, p = 0.48) and disease-free survival (p = 0.61, p = 0.14).

CONCLUSION

In this study the expression of synuclein-y and glucose transporter-1 were not considered to be a prognostic factor and were not related with survival outcomes in endometrioid endometrial carcinoma.

Regional cerebellar volume reflects static balance in elite female short-track speed skaters

The cerebellum plays a critical role in balance control. Particularly, elite short-track speed skaters require fine postural control to keep a postural balance during high velocity movement across smooth ice. We investigated whether skating proficiency and gender have an effect on the volume of cerebellar subregions and static balance, using 3-dimensional magnetic resonance imaging volumetry. In addition, we further analyzed which subregions of the cerebellum correlates with the balance. The volumes of cerebellar subregions and static balance index were compared among 12 male and 11 female elite short-track speed skaters, and 11 male and 14 female healthy matched subjects. We found significant main effects of skating proficiency and gender on the volume of vermian lobule VI-VII (declive, folium, and tuber), short-track speed skaters having greater volume than control and women revealing greater volume than men. Especially, in female athletic group, the volume of vermian lobule VI-VII significantly correlates with left static balance. In addition, men showed larger skating proficiency-related differences than women in the performance of static balance. The correlation between the volume of this region and static balance in female short-track speed skaters suggests that this region would plays a critical role in balance.

Aneurysmal subarachnoid hemorrhage in third and fourth decades of life

Objective

The aim of this study was to compare clinical characteristics of ruptured aneurysms in young adults, of the third and fourth decades of life, and to compare several clinical characteristics affecting the outcome of patients.

Methods

We retrospectively investigated 1459 patients who underwent surgery and endovascular treatment for ruptured cerebral aneurysms from June 1992 to December 2010 and compared clinical characteristics. We also reviewed pre-existing medical conditions and perioperative complications.

Results

Among 1459 patients, there were 21 patients (1.44%) in the third decade and 104 patients (7.13%) in the fourth decade of life. Within two age groups, 88 (70.4%) were male and 37 (29.6%) were female, a ratio of 2.37 : 1. In both groups, we observed the anterior cerebral artery (ACA) aneurysm with the most frequency (p=0.028). In general, favorable outcome was achieved in both age groups (90.5% and 81.7%, respectively). An initial univariate analysis showed Hunt-Hess grade, Fisher grade, location of aneurysm, and rebleeding significantly associated with outcome after aneurysm rupture. Further, multivariate analysis demonstrated that only Hunt-Hess grade (grade 4-5) was a risk factor for the outcome (odds ratio=9.730, 95% confidence interval 2.069-45.756, p=0.004).

Conclusion

The incidence of subarachnoid hemorrhage (SAH) was higher in the male population of the third and fourth decades of life. Aneurysms on the ACA were most frequently occurred in both age groups and the outcome of aneurysmal SAH among the third and fourth decades was favorable. Multivariate analysis revealed that high Hunt-Hess grade was a risk factor for patient's outcome.

The analysis of patterns and risk factors of newly developed vertebral compression fractures after percutaneous vertebroplasty

OBJECTIVE

The purpose of this study was to investigate the patterns and the risk factors of newly developed vertebral compression fractures (VCFs) after percutaneous vertebroplasty (PVP).

METHODS

We performed a retrospective review of the 244 patients treated with PVP from September 2006 to February 2011. Among these patients, we selected 49 patients with newly developed VCFs following PVP as the new VCFs group, and the remaining 195 patients as the no VCFs group. The new VCFs group was further divided into 2 groups : an adjacent fractures group and a nonadjacent fractures group. The following data were collected from the groups : age, gender, body weight/height, body mass index (BMI), bone mineral density (BMD) score of the spine and femur, level of initial fracture, restoration rate of anterior/middle vertebral height, and intradiscal cement leakage, volume of polymethylmethacrylate (PMMA).

RESULTS

Age, gender, mean body height/weight, mean BMI and volume of PMMA of each of the group are not statistically significantly associated with fractures. In comparison between the new VCFs group and the no VCFs group, lower BMD, intradiscal cement leakage and anterior vertebral height restoration were the significant predictive factors of the fracture. In addition, new VCFs occurrence at the adjacent spines was statistically significant, when the initial fracture levels were confined to the thoracolumbar junction, among the subgroups of new VCFs.

CONCLUSION

Lower spinal BMD, the greater anterior vertebral height restoration rate and intradiscal cement leakage were confirmed as risk factors for newly formed VCFs after PVP.

Kimura disease: CT and MR imaging findings

BACKGROUND AND PURPOSE

KD is a rare chronic inflammatory disorder of unknown etiology. The purpose of this study was to evaluate the CT and MR imaging findings of KD in the head and neck.

MATERIALS AND METHODS

We retrospectively reviewed the CT (n = 21) and MR (n = 9) images obtained in 28 patients (24 males and 4 females; mean age, 32 years; age range, 10-62 years) with histologically proved KD in the head and neck.

RESULTS

In these 28 patients, CT and MR images demonstrated a total of 52 non-nodal lesions, 1-8 cm in greatest diameter, in the head and neck. The lesions were unilateral in 11 patients and bilateral in 17 patients. Eleven patients had a solitary lesion, and 17 patients had 2-4 lesions. The parotid and/or periparotid area was the most frequent location, with 36 lesions in 23 patients. The margin of the lesions was well-defined in 1 and ill-defined in 51 cases. Compared with the adjacent muscle, the MR signal intensity of all lesions was iso- to slightly hyperintense on T1-weighted images and hyperintense on T2-weighted images. Most of the lesions demonstrated mild or moderate enhancement on postcontrast CT scans and moderate or marked enhancement on postcontrast MR images. MR images also showed tubular signal-intensity voids in 7 of 13 lesions. Associated lymphadenopathy was demonstrated in 23 patients, usually bilaterally.

CONCLUSIONS

Multiple ill-defined enhancing masses within and around the parotid gland with associated regional lymphadenopathy are characteristic CT and MR imaging findings of KD in the head and neck.

Efficient and accurate analysis of mitochondrial morphology in a whole cell with a high-voltage electron microscopy

Mitochondria in all eukaryotes are essential organelles responsible for adenosine triphosphate synthesis, calcium homeostasis and steroidogenesis. Because the structure and distribution of mitochondria are highly diverse depending on their function and cellular conditions, it is important to develop a rapid and accurate method to assess their morphology. In this study, we visualize whole mitochondria in cultured cells using high-voltage electron microscopy (HVEM). Compared with conventional transmission electron microscopic approaches, the present method does not require thin sectioning and thus requires less time for image acquisition and processing. Furthermore, compared with fluorescence-based light microscopic approaches, our method provides more accurate size information. Thus, we propose that HVEM is a useful tool for rapid and accurate analysis of mitochondrial morphology and distribution in a cell.

Inferolateral entry point for c2 pedicle screw fixation in high cervical lesions

OBJECTIVE

The purpose of this retrospective study was to evaluate the efficacy and safety of atlantoaxial stabilization using a new entry point for C2 pedicle screw fixation.

METHODS

Data were collected from 44 patients undergoing posterior C1 lateral mass screw and C2 screw fixation. The 20 cases were approached by the Harms entry point, 21 by the inferolateral point, and three by pars screw. The new inferolateral entry point of the C2 pedicle was located about 3-5 mm medial to the lateral border of the C2 lateral mass and 5-7 mm superior to the inferior border of the C2-3 facet joint. The screw was inserted at an angle 30° to 45° toward the midline in the transverse plane and 40° to 50° cephalad in the sagittal plane. Patients received followed-up with clinical examinations, radiographs and/or CT scans.

RESULTS

There were 28 males and 16 females. No neurological deterioration or vertebral artery injuries were observed. Five cases showed malpositioned screws (2.84%), with four of the screws showing cortical breaches of the transverse foramen. There were no clinical consequences for these five patients. One screw in the C1 lateral mass had a medial cortical breach. None of the screws were malpositioned in patients treated using the new entry point. There was a significant relationship between two group (p=0.036).

CONCLUSION

Posterior C1-2 screw fixation can be performed safely using the new inferolateral entry point for C2 pedicle screw fixation for the treatment of high cervical lesions.

Is titanium mesh cage safe in surgical management of pyogenic spondylitis?

OBJECTIVE

To report our experience with pyogenic spondylitis treated with anterior radical debridement and insertion of a titanium mesh cage and to demonstrate the effectiveness and safety of the use of a titanium mesh cage in the surgical management of pyogenic spondylitis.

METHODS

We retrospectively analyzed the clinical characteristics of 19 patients who underwent surgical treatment in our department between January 2004 and December 2008. The average follow-up period was 11.16 months (range, 6-64 months). We evaluated risk factors, cultured organisms, lab data, clinical outcomes, and radiographic results. Surgical techniques for patients with pyogenic spondylitis were anterior radical debridement and reconstruction with titanium mesh cage insertion and screw fixation. All patients received intravenous antibiotics for at least 6 weeks postoperatively, and some patients received oral antibiotics.

RESULTS

The infections resolved in all of the patients as noted by normalization of their erythrocyte sedimentation rates and C-reactive protein levels. The mean pain score on a Visual Analog Scale was 7.8 (range, 4-10) before surgery and 2.4 (range, 1-5) after surgery. The Frankel grade was improved by one grade in seven patients. After surgery, the average difference of the angle was improved about 6.96° in all patients. At the last follow-up, the mean loss of correction was 4.86°.

CONCLUSION

Anterior radical debridement followed by the placement of instrumentation with a titanium mesh cage may be a safe and effective treatment for selected patients with pyogenic spondylitis. This surgical therapy does not lead to recurrent pyogenic spondylitis.