Cilostazol restores autophagy flux in bafilomycin A1-treated, cultured cortical astrocytes through lysosomal reacidification: roles of PKA, zinc and metallothionein 3.

Cilostazol, a phosphodiesterase 3 inhibitor, reduces the amyloid-beta (Aß) burden in mouse models of Alzheimer disease by as yet unidentified mechanisms. In the present study, we examined the possibility that cilostazol ameliorates lysosomal dysfunction. Astrocytes treated with bafilomycin A1 (BafA1) exhibited markedly reduced DND-189 and acridine orange (AO) fluorescence, indicating reduced lysosomal acidity. In both cases, BafA1-induced alkalization was reversed by addition of cilostazol, dibutyryl cAMP or forskolin. All three agents significantly increased free zinc levels in lysosomes, and addition of the zinc chelator TPEN abrogated lysosomal reacidification. These treatments did not raise free zinc levels or reverse BafA1-mediated lysosomal alkalization in metallothionein 3 (Mt3)-null astrocytes, indicating that the increases in zinc in astrocytes were derived mainly from Mt3. Lastly, in FITC-Aß-treated astrocytes, cilostazol reversed lysosomal alkalization, increased cathepsin D activity, and reduced Aß accumulation in astrocytes. Cilostazol also reduced mHtt aggregate formation in GFP-mHttQ74-expressing astrocytes. Collectively, our results present the novel finding that cAMP/PKA can overcome the v-ATPase blocking effect of BafA1 in a zinc- and Mt3-dependent manner.

Vasa Vasorum Densities in Human Carotid Atherosclerosis Is Associated with Plaque Development and Vulnerability.

OBJECTIVE: The extensive vasa vasorum network functions as a conduit for the entry of inflammatory cells or factors that promote the progression of angiogenesis and plaque formation. Therefore, we investigated the correlation between the carotid vasa vasorum activities and carotid plaque vulnerability using indocyanine green video angiography (ICG-VA) during carotid endarterectomy (CEA). METHODS: Sixty-nine patients who underwent CEA were enrolled prospectively from September 2015 to December 2017. During CEA, a bolus of ICG was injected intravenously before and after resecting the atheroma. Additionally, we performed immunohistochemistry using CD68 (a surface marker of macrophages), CD117 (a surface marker of mast cells), and CD4 and CD8 (surface markers of T-cells) antibodies to analyze the resected plaque specimens. RESULTS: The density of active vasa vasorum was observed in all patients using ICG-VA. The vasa vasorum externa (VVE) and interna (VVI) were seen in 11 (16%) and 57 patients (82.6%), respectively. Macroscopically, the VVE-type patterns were strongly associated with preoperative angiographic instability (81.8%, p=0.005) and carotid plaque vulnerability (90.9%, p=0.017). In contrast, the VVI-type patterns were weakly associated with angiographic instability (31.6%) and plaque vulnerability (49.1%). CD68-stained macrophages and CD117-stained mast cells were observed more frequently in unstable plaques than in stable plaques (p<0.0001, p=0.002, respectively). CONCLUSION: The early appearance of VVE, along with the presence of many microvessel channels that provided nutrients to the developing and expanding atheroma during ICG-VA, was strongly associated with unstable carotid plaques. The degree of infiltration of macrophages and mast cells is possibly related to the formation of unstable plaques.

Identifying New AMP-Activated Protein Kinase Inhibitors That Protect against Ischemic Brain Injury.

We recently reported that AMP-activated protein kinase (AMPK) contributes to zinc-induced neuronal death by inducing Bim, a pro-apoptotic Bcl-2 homology domain 3-only protein, in a liver kinase B1 (LKB1)-dependent manner. Current data suggest AMPK plays key roles in excitotoxicity and ischemic brain injury, with zinc neurotoxicity representing at least one mechanism of ischemic neuronal death. Inhibition of AMPK could be a viable therapeutic strategy to prevent ischemic brain injury following stroke. This prompted our search for novel inhibitors of AMPK activity and zinc-induced neuronal death using cultured mouse cortex and a rat model of brain injury after middle cerebral artery occlusion (MCAO). In structure-based virtual screening, 118 compounds were predicted to bind the active site of AMPK α2, and 40 showed in vitro AMPK α2 inhibitory activity comparable to compound C (a well-known, potent AMPK inhibitor). In mouse cortical neuronal cultures, 7 of 40 compound reduced zinc-induced neuronal death at levels comparable to compound C. Ultimately, only agents 2G11 and 1H10 significantly attenuated various types of neuronal death, including oxidative stress, excitotoxicity, and apoptosis. When administered as intracerebroventricular injections prior to permanent MCAO in rats, 2G11 and 1H10 reduced brain infarct volumes, whereas compound C did not. Therefore, these novel AMPK inhibitors could be drug development candidates to treat stroke.

Contribution of Zinc-Dependent Delayed Calcium Influx via TRPC5 in Oxidative Neuronal Death and its Prevention by Novel TRPC Antagonist.

Oxidative stress is a key mediator of neuronal death in acute brain injuries, such as epilepsy, trauma, and stroke. Although it is accompanied by diverse cellular changes, increases in levels of intracellular zinc ion (Zn2+) and calcium ion (Ca2+) may play a critical causative role in oxidative neuronal death. However, the mechanistic link between Zn2+ and Ca2+ dyshomeostasis in neurons during oxidative stress is not well-understood. Here, we show that the exposure of cortical neurons to H2O2 led to a zinc-triggered calcium influx, which resulted in neuronal death. The cyclin-dependent kinase inhibitor, NU6027, inhibited H2O2-induced Ca2+ increases and subsequent cell death in cortical neurons, without affecting the early increase in Zn2+. Therefore, we attempted to identify the zinc-regulated Ca2+ pathway that was inhibited by NU6027. The expression profile in cortical neurons identified transient receptor potential cation channel 5 (TRPC5) as a candidate that is known to involve in the generation of epileptiform burst firing and epileptic neuronal death (Phelan KD et al. 2012a; Phelan KD et al. 2013b). NU6027 inhibited basal and zinc-augmented TRPC5 currents in TRPC5-overexpressing HEK293 cells. Consistently, cortical neurons from TRPC5 knockout mice were highly resistant to H2O2-induced death. Moreover, NU6027 is neuroprotective in kainate-treated epileptic rats. Our results demonstrate that TRPC5 is a novel therapeutic target against oxidative neuronal injury in prolonged seizures and that NU6027 is a potent inhibitor of TRPC5.

Correction to: Contribution of Zinc-Dependent Delayed Calcium Influx via TRPC5 in Oxidative Neuronal Death and its Prevention by Novel TRPC Antagonist.

After the publication of this work errors were noticed in Fig. 3b and 4d.

Potential Role of Zinc Dyshomeostasis in Matrix Metalloproteinase-2 and -9 Activation and Photoreceptor Cell Death in Experimental Retinal Detachment.

Purpose: We investigated whether zinc dyshomeostasis, a known mechanism of cell death in acute brain injury, contributes to the activation of matrix metalloproteinases (MMPs) and photoreceptor cell death in experimental retinal detachment (RD). Methods: RD was induced in mice by subretinal injection of 1:1 mixture of balanced salt solution and 1% sodium hyaluronate. On days 1 and 3 post RD, eyeballs were sectioned and examined for cell death (TUNEL staining), the degree of hypoxic insult (Hypoxyprobe staining), free zinc levels (TFL-Zn staining), and MMP-2 and -9 activity (gelatin zymography). In addition, we examined whether modulating extracellular zinc concentration or MMP activation in subretinal fluid affected photoreceptor cell death in RD. These changes were further examined in primary retinal cell and photoreceptor-derived cell (661W) cultures. Results: Photoreceptor cell death peaked on day 3 post RD. Intracellular zinc markedly decreased on day 1 post RD, and subsequently accumulated on day 3. MMP-2 and -9 activity showed a concurrent increase in detached retinas. Detached retinas stained with Hypoxyprobe showed strongly positive cells, especially in the photoreceptor layer. Subretinal injection of a zinc-chelator (CaEDTA) or MMP inhibitor (GM6001, minocycline) at the time of RD significantly attenuated photoreceptor cell death in RD. Similar findings were confirmed in oxygen-glucose-deprived or zinc-exposed cell cultures. Conclusions: Upon RD, hypoxic retinal cells in deep layers underwent zinc dyshomeostasis, MMP activation, and ultimately death. These findings provide new insight into the possible mechanism of photoreceptor death in RD, and as such may prove useful in crafting protective measures for photoreceptor cells.

Metallothionein-3 modulates the amyloid ß endocytosis of astrocytes through its effects on actin polymerization.

BACKGROUND: Astrocytes may play important roles in the pathogenesis of Alzheimer's disease (AD) by clearing extracellular amyloid beta (Aß) through endocytosis and degradation. We recently showed that metallothionein 3 (Mt3), a zinc-binding metallothionein that is enriched in the central nervous system, contributes to actin polymerization in astrocytes. Because actin is likely involved in the endocytosis of Aß, we investigated the possible role of Mt3 in Aß endocytosis by cortical astrocytes in this study. RESULTS: To assess the route of Aß uptake, we exposed cultured astrocytes to fluorescently labeled Aß1-40 or Aß1-42 together with chloropromazine (CP) or methyl-beta-cyclodextrin (MßCD), inhibitors of clathrin- and caveolin-dependent endocytosis, respectively. CP treatment almost completely blocked Aß1-40 and Aß1-42 endocytosis, whereas exposure to MßCD had no significant effect. Actin disruption with cytochalasin D (CytD) or latrunculin B also completely blocked Aß1-40 and Aß1-42 endocytosis. Because the absence of Mt3 also results in actin disruption, we examined Aß1-40 and Aß1-42 uptake and expression in Mt3 (-/-) astrocytes. Compared with wild-type (WT) cells, Mt3 (-/-) cells exhibited markedly reduced Aß1-40 and Aß1-42 endocytosis and expression of Aß1-42 monomers and oligomers. A similar reduction was observed in CytD-treated WT cells. Finally, actin disruption and Mt3 knockout each increased the overall levels of clathrin and the associated protein phosphatidylinositol-binding clathrin assembly protein (PICALM) in astrocytes. CONCLUSIONS: Our results suggest that the absence of Mt3 reduces Aß uptake in astrocytes through an abnormality in actin polymerization. In light of evidence that Mt3 is downregulated in AD, our findings indicate that this mechanism may contribute to the extracellular accumulation of Aß in this disease.

The zinc ionophore clioquinol reverses autophagy arrest in chloroquine-treated ARPE-19 cells and in APP/mutant presenilin-1-transfected Chinese hamster ovary cells.

Arrested autophagy may contribute to the pathogenesis of Alzheimer's disease. Because we found that chloroquine (CQ) causes arrested autophagy but clioquinol (ClioQ), a zinc ionophore, activates autophagic flux, in the present study, we examined whether ClioQ can overcome arrested autophagy induced by CQ or mutant presenilin-1 (mPS1). CQ induced vacuole formation and cell death in adult retinal pigment epithelial (ARPE-19) cells, but co-treatment with ClioQ attenuated CQ-associated toxicity in a zinc-dependent manner. Increases in lysosome dilation and blockage of autophagic flux by CQ were also markedly attenuated by ClioQ treatment. Interestingly, CQ increased lysosomal pH in amyloid precursor protein (APP)/mPS1-expressing Chinese hamster ovary 7WΔE9 (CHO-7WΔE9) cell line, and ClioQ partially re-acidified lysosomes. Furthermore, accumulation of amyloid-ß (Aß) oligomers in CHO-7WΔE9 cells was markedly attenuated by ClioQ. Moreover, intracellular accumulation of exogenously applied fluorescein isothiocyanate-conjugated Aß(1-42) was also increased by CQ but was returned to control levels by ClioQ. These results suggest that modulation of lysosomal functions by manipulating lysosomal zinc levels may be a useful strategy for clearing intracellular Aß oligomers.

Arachnoid Membrane Suturing for Prevention of Subdural Fluid Collection in Extracranial-intracranial Bypass Surgery.

OBJECTIVE: Water-tight closure of the dura in extracranial-intracranial (EC-IC) bypass is impossible because the superficial temporal artery (STA) must run through the dural defect. Consequently, subdural hygroma and subcutaneous cerebrospinal fluid (CSF) collection frequently occur postoperatively. To reduce these complications, we prospectively performed suturing of the arachnoid membrane after STA-middle cerebral artery (STA-MCA) and evaluated the clinical usefulness. MATERIALS AND METHODS: Between Mar. 2005 and Oct. 2010, extracranial-intracranial arterial bypass (EIAB) with/without encephalo-myo-synangiosis was performed in 88 cases (male : female = 53 : 35). As a control group, 51 patients (57 sides) underwent conventional bypass surgery without closure of the arachnoid membrane. Postoperative computed tomography (CT) scan was performed twice in three days and seven days later, respectively, for evaluation of the presence of subdural fluid collection and other mass lesions. RESULTS: The surgical result was excellent, with no newly developing ischemic event until recent follow-up. The additional time needed for arachnoid suture was five to ten minutes, when three to eight sutures were required. Post-operative subdural fluid collection was not seen on follow-up computed tomography scans in all patients. CONCLUSION: Arachnoid suturing is simple, safe, and effective for prevention of subdural fluid collection in EC-IC bypass surgery, especially the vulnerable ischemic hemisphere.

The role of reciprocal activation of cAbl and Mst1 in the oxidative death of cultured astrocytes.

The protein kinase Mst1 (mammalian Sterile 20-like kinase 1) likely plays a role in oxidative neuronal cell death as a target of its activator, cAbl. We previously found that H2O2-induced death of astrocytes is mediated by cAbl in a metallothionein-3 (Mt3)-dependent manner. In the present study, we examined a possible role for Mst1 in the oxidative death of astrocytes. Treatment of cortical astrocytes with 170 µM H2O2 activated Mst1. Knockdown of Mst1 reduced H2O2-induced cell death, indicating that Mst1 activation contributes to astrocytic cell death. STI571, an inhibitor of cAbl, blocked induction/activation of Mst1 and H2O2-induced cell death. However, Mst1 silencing also inhibited induction/activation of cAbl, suggesting that the two kinases are regulated by a reciprocal activating mechanism. The zinc chelator TPEN blocked induction/activation of cAbl and Mst1, indicating that these phenomena are dependent on the rise of intracellular zinc. Moreover, H2O2 exposure did not increase free zinc levels in Mt3-null astrocytes, suggesting that the increased levels of free zinc were largely from Mt3. Consistent with the involvement of FoxO1/3, which may play a role in the Mst1-cell death cascade, we found an increase in the level of phosphorylated FoxO1/3 in H2O2-treated astrocytes. Moreover, inhibition of cAbl or Mst1 reversed this effect. The present results suggest the interesting possibility that cAbl and Mst1 are reciprocally activated under oxidative stress conditions in astrocytes. Both kinases appear to be regulated by changes in the levels of free zinc originating from Mt3 and contribute to oxidative cell death through a FoxO-dependent mechanism.

Evaluation of probability of survival using trauma and injury severity score method in severe neurotrauma patients.

OBJECTIVE: Despite several limitations, the Trauma Injury Severity Score (TRISS) is normally used to evaluate trauma systems. The aim of this study was to evaluate the preventable trauma death rate using the TRISS method in severe trauma patients with traumatic brain injury using our emergency department data. METHODS: The use of the TRISS formula has been suggested to consider definitively preventable death (DP); the deaths occurred with a probability of survival (Ps) higher than 0.50 and possible preventable death (PP); the deaths occurred with a Ps between 0.50 and 0.25. Deaths in patients with a calculated Ps of less than 0.25 is considered as no-preventable death (NP). A retrospective case review of deaths attributed to mechanical trauma occurring between January 1, 2011 and December 31, 2011 was conducted. RESULTS: A total of 565 consecutive severe trauma patients with ISS>15 or Revised Trauma Score<7 were admitted in our institute. We excluded a total of 24 patients from our analysis : 22 patients younger than 15 years, and 2 patients with burned injury. Of these, 221 patients with head injury were analyzed in the final study. One hundred eighty-two patients were in DP, 13 in PP and 24 in NP. The calculated predicted mortality rates were 11.13%, 59.04%, and 90.09%. The actual mortality rates were 12.64%, 61.547%, and 91.67%, respectively. CONCLUSION: Although it needs to make some improvements, the present study showed that TRISS performed well in predicting survival of traumatic brain injured patients. Also, TRISS is relatively exact and acceptable compared with actual data, as a simple and time-saving method.

Value of indocyanine green videoangiography in deciding the completeness of cerebrovascular surgery.

OBJECTIVE: Recently, microscope-integrated near infrared indocyanine green videoangiography (ICG-VA) has been widely used in cerebrovascular surgery because it provides real-time high resolution images. In our study, we evaluate the efficacy of intraoperative ICG-VA during cerebrovascular surgery. METHODS: Between August 2011 and April 2012, 188 patients with cerebrovascular disease were surgically treated in our institution. We used ICG-VA in that operations with half of recommended dose (0.2 to 0.3 mg/kg). Postoperative digital subtraction angiography and computed tomography angiography was used to confirm anatomical results. RESULTS: Intraoperative ICG-VA demonstrated fully occluded aneurysm sack, no neck remnant, and without vessel compromise in 119 cases (93.7%) of 127 aneurysms. Eight clipping (6.3%) of 127 operations were identified as an incomplete aneurysm occlusion or compromising vessel after ICG-VA. In 41 (97.6%) of 42 patients after carotid endarterectomy, the results were the same as that of postoperative angiography with good patency. One case (5.9%) of 17 bypass surgeries was identified as a nonfunctioning anastomosis after ICG-VA, which could be revised successfully. In the two patients of arteriovenous malformation, ICG-VA was useful for find the superficial nature of the feeding arteries and draining veins. CONCLUSION: ICG-VA is simple and provides real-time information of the patency of vessels including very small perforators within the field of the microscope and has a lower rate of adverse reactions. However, ICG-VA is not a perfect method, and so a combination of monitoring tools assures the quality of cerebrovascular surgery.

The usefulness of electromagnetic neuronavigation in the pediatric neuroendoscopic surgery.

OBJECTIVE: Neuroendoscopy is applied to various intracranial pathologic conditions. But this technique needs informations for the anatomy, critically. Neuronavigation makes the operation more safe, exact and lesser invasive procedures. But classical neuronavigation systems with rigid pinning fixations were difficult to apply to pediatric populations because of their thin and immature skull. Electromagnetic neuronavigation has used in the very young patients because it does not need rigid pinning fixations. The usefulness of electromagnetic neuronavigation is described through our experiences of neuroendoscopy for pediatric groups and reviews for several literatures. METHODS: Between January 2007 and July 2011, nine pediatric patients were managed with endoscopic surgery using electromagnetic neuronavigation (AxiEM, Medtronics, USA). The patients were 4.0 years of mean age (4 months-12 years) and consisted of 8 boys and 1 girl. Totally, 11 endoscopic procedures were performed. The cases involving surgical outcomes were reviewed. RESULTS: The goal of surgery was achieved successfully at the time of surgery, as confirmed by postoperative imaging. In 2 patients, each patient underwent re-operations due to the aggravation of the previous lesion. And one had transient mild third nerve palsy due to intraoperative manipulation and the others had no surgery related complication. CONCLUSION: By using electromagnetic neuronavigation, neuroendoscopy was found to be a safe and effective technique. In conclusion, electromagnetic neuronavigation is a useful adjunct to neuroendoscopy in very young pediatric patients and an alternative to classical optical neuronavigation.

Early clinical characteristics according to developmental stage in children with definite moyamoya disease.

The objective is to clarify the early clinical characteristics in childhood moyamoya disease (MD). Epidemiologic characteristics, symptoms and diagnostic rates were assessed in 64 children (0-18 years) with definite MD according to developmental stage: infancy (5; 0-1 years); toddlerhood/preschool age (22; 2-5 years); school age (29; 6-10 years); and adolescence (8; 11-18 years). The median ages at onset was 6.25 years and the female to male ratio was 1.9 (~2.5 in toddlerhood/preschool age and in adolescence, P=0.71). Previous headache was observed in 23% (14/64): frequently in school age (38%, P=0.02) and within 6 months before main symptoms (6/11). As an initial symptom, weakness was observed in 78% (50/64) mainly as transient ischemic attack (TIA, 61%) in limbs (90%) and unilaterally (82%). TIA was less frequent in infancy (40%, P=0.04). Seizure was observed in 27% (17/64): frequently in infancy (100%, P<0.01), as the focal type (71%), and in the right extremity (3:1). Isolated seizures without other symptoms was frequent in children ~5 years (P<0.01). Severe headache associated with MD was observed in 14% (9/64). Provoking events were positive in 42% (27/64): in school age, frequently during eating (28%); and in toddlerhood/preschool age, during crying (27%). The diagnostic rates at 3 and 12 months from symptom-onset were 39% (80% during infancy vs. 28% in school age, P=0.14) and 67%, respectively. Symptomatic progression at diagnosis was observed in 38% (24/64). Initial clinical characteristics in childhood definite MD differed according to developmental stage and from at diagnosis.

Laminotomy with continuous irrigation in patients with pyogenic spondylitis in thoracic and lumbar spine.

OBJECTIVE: Pyogenic spondylitis often results in acute neurological deterioration requiring adequate surgical intervention and appropriate antibiotic treatment. The purpose of this study was to conduct an analysis of the clinical effect of continuous irrigation via laminotomy in a series of patients with pyogenic spondylitis in thoracic and lumbar spine. METHODS: The authors conducted a retrospective investigation of 31 consecutive patients with pyogenic thoracic and lumbar spondylitis who underwent continuous irrigation through laminotomy from 2004 to 2008. The study included 22 men and 9 women, ranging in age from 38 to 78 years (mean 58.1 years). The average follow-up duration was 13.4 months (range, 8-34 months). We performed debridement and abscess removal after simple laminotomy, and then washed out epidural and disc space using a continuous irrigation system. Broad spectrum antibiotics were administered empirically and changed according to the subsequent culture result. Clinical outcomes were based on the low back outcome scale (LBOS), visual analogue scale (VAS) score, and Frankel grade at the last follow-up. Radiological assessment involved plain radiographs, including functional views. RESULTS: Common predisposing factors included local injection for pain therapy, diabetes mellitus, chronic renal failure, and liver cirrhosis. Causative microorganisms were identified in 22 cases (70.9%) : Staphylococcus aureus and Streptococcus spp. were the main organisms. After surgery, LBOS, VAS score, and Frankel grade showed significant improvement in most patients. Spinal stability was maintained during the follow-up period, making secondary reconstructive surgery unnecessary for all patients, except one. CONCLUSION: Simple laminotomy with continuous irrigation by insertion of a catheter into intervertebral disc space or epidural space was minimally invasive and effective in the treatment of pyogenic spondylitis. This procedure could be a beneficial treatment option in patients with thoracolumbar spondylitis combined with minimal or moderate destructive change of vertebrae.

Post-traumatic cerebral infarction : outcome after decompressive hemicraniectomy for the treatment of traumatic brain injury.

OBJECTIVE: Posttraumatic cerebral infarction (PTCI), an infarction in well-defined arterial distributions after head trauma, is a known complication in patients with severe head trauma. The primary aims of this study were to evaluate the clinical and radiographic characteristics of PTCI, and to assess the effect on outcome of decompressive hemicraniectomy (DHC) in patients with PTCI. METHODS: We present a retrospective analysis of 20 patients with PTCI who were treated between January 2003 and August 2005. Twelve patients among them showed malignant PTCI, which is defined as PTCI including the territory of Middle Cerebral Artery (MCA). Medical records and radiologic imaging studies of patients were reviewed. RESULTS: Infarction of posterior cerebral artery distribution was the most common site of PTCI. Fourteen patients underwent DHC an average of 16 hours after trauma. The overall mortality rate was 75%. Glasgow outcome scale (GOS) of survivors showed that one patient was remained in a persistent vegetative state, two patients were severely disabled and only two patients were moderately disabled at the time of discharge. Despite aggressive treatments, all patients with malignant PTCI had died. Malignant PTCI was the indicator of poor clinical outcome. Furthermore, Glasgow coma scale (GCS) at the admission was the most valuable prognostic factor. Significant correlation was observed between a GCS less than 5 on admission and high mortality (p<0.05). CONCLUSION: In patients who developed non-malignant PTCI and GCS higher than 5 after head injury, early DHC and duroplasty should be considered, before occurrence of irreversible ischemic brain damage. High mortality rate was observed in patients with malignant PTCI or PTCI with a GCS of 3-5 at the admission. A large prospective randomized controlled study will be required to justify for aggressive treatments including DHC and medical treatment in these patients.

Endoscopic treatment of transnasal intracranial penetrating foreign body.

Transnasal intracranial penetrating injury is rare. We report a case of transnasal intracranial penetrating metallic chopstick, which was removed successfully by endoscopic approach, and management of transnasal intracranial penetrating injuries.

Inhibitory effect of Aralia continentalis on the cariogenic properties of Streptococcus mutans.

ETHNOPHARMACOLOGICAL RELEVANCE: Aralia continentalis has been used in traditional Korean medicine for dental diseases such as toothache, dental caries, periodontal disease and gingivitis, and also has been used for neuralgia, analgesia, sweating, and as an antirheumatic. AIM OF THE STUDY: The present study was designed to investigate the inhibitory effect of Aralia continentalis extract on cariogenic properties of Streptococcus mutans, which is one of the most important bacteria in the formation of dental caries and dental plaque. MATERIALS AND METHODS: The inhibitory effects of Aralia continentalis extract on the growth, acid production, water-insoluble glucan synthesis, and adhesion were investigated in Streptococcus mutans. The biofilm formation of Streptococcus mutans was determined by scanning electron microscopy (SEM) and safranin staining. RESULTS: The ethanol extract of Aralia continentalis showed concentration dependent inhibitory activity on the growth of Streptococcus mutans and significant inhibition of acid production at the concentrations of 0.25, 0.5, 1, 2 and 4 mg/ml compared to the control group. The synthesis of water-insoluble glucan by glucosyltransferase (GTFase) was decreased in the presence of 0.5-4 mg/ml of the extract of Aralia continentalis. The extract markedly inhibited Streptococcus mutans adherence to saliva-coated hydroxyapatite beads (S-HAs). The extract of Aralia continentalis has an inhibitory effect on the formation of Streptococcus mutans biofilms at the concentrations higher than 2mg/ml. CONCLUSIONS: These results suggest that Aralia continentalis may inhibit cariogenic properties of Streptococcus mutans, and also may support the scientific rationale that native inhabitants used the extract for the treatment of dental diseases.

Vertebral artery injury after cervical spine trauma: A prospective study using computed tomographic angiography.

BACKGROUND: Although the vertebral artery injuries (VAI) associated with cervical spine trauma are usually clinically occult, they may cause fatal ischemic damage to the brain stem and cerebellum. METHODS: We performed a prospective study using computed tomographic angiography (CTA) to determine the frequency of VAI associated with cervical spine injuries and investigate the clinical and radiological characteristics. Between January 2005 and August 2007, 99 consecutive patients with cervical spine fractures and/or dislocations were prospectively evaluated for patency of the VA, using the CTA, at the time of injury. RESULTS: Complete disruption of blood flow through the VA was demonstrated in seven patients with unilateral occlusion (7.1%). There were four men and three women with a mean age of 43 (range, 33-55 years). Unilateral occlusion of the right vertebral artery occurred in four patients and of the left in three. Regarding the cervical injury type, two cases were cervical burst fractures (C6 and C7), two had C4-5 fracture/dislocations, two had a unilateral transverse foraminal fracture, and one had dens type III fracture. All patients presented with good patency of the contralateral VA. None of the patients developed secondary neurological deterioration due to vertebrobasilar ischemia during the follow-up period with a mean duration of 23 months. CONCLUSIONS: VAI should be suspected in patients with cervical trauma that have cervical spine fractures and/or dislocations or transverse foramen fractures. CTA was useful as a rapid diagnostic method for ruling out VAI after cervical spine trauma.

Rapid progression of unilateral moyamoya disease.

The detailed clinical characteristics of unilateral moyamoya disease (MMD) have not been fully elucidated. It has been reported that some patients with unilateral MMD progress to bilateral involvement, while others remain with the unilateral variant. In this series, we present a case of unilateral MMD that progressed to bilateral involvement over the course of just one month.