Diagnosis of osteochondral lesions of the talus on Dual-layer spectral detector CT arthrography: clinical feasibility of virtual noncontrast images

AIM

To compare the image quality of virtual noncontrast (VNC) and true noncontrast (TNC) CT images and to evaluate the clinical feasibility of VNC CT images for assessing osteochondral lesions of the talus (OLTs).

MATERIALS AND METHODS

Forty-five OLT patients who underwent ankle CT arthrography (CTA) using dual-layer spectral detector CT were enrolled. Reconstruction of VNC and three-dimensional volume rendering images was performed. Afterward, image noise, the signal-to-noise ratio (SNR), and the contrast-to-noise ratio (CNR) were measured. For the subjective evaluation, two board-certified musculoskeletal radiologists [R2-1] assessed spatial resolution, overall image quality, and lesion conspicuity. The accuracy rate for OLT grading was determined in 23 patients who underwent arthroscopic surgery.

RESULTS

While VNC images showed significantly less noise than TNC images, TNC images showed better SNRs and CNRs (p<.01). In the subjective analysis, TNC images showed better overall image quality (p<.001). For the 3D volume rendering images, VNC images scored significantly higher for lesion conspicuity (p<.001). The accuracy rates of CTA and CTA with VNC images for OLT grading were 79.2% and 83.3%, respectively. Regarding confidence level, when CTA and VNC images were evaluated together, the confidence level was significantly higher than that when only CTA images were evaluated (p<.001).

CONCLUSION

VNC imaging can provide better confidence level of OLT grading and evaluation of the integrity of the subchondral bone plate when combined with conventional CTA without additional radiation dose to the patient. In addition, VNC images-based 3D volume rendering reconstruction would be helpful for preoperative planning in OLT patients.

Outbreak associated with Rotavirus G11,P[25] in Korea in 2018

We here report the first outbreak caused by rotavirus G11,P[25] in Korea in 2018, representing a case of re-assortment with pig-derived rotavirus. The genotype constellation was identical to the virus identified in Korea in 2012 as G11-P[25]-I12-R1-C1-M1-A1-N1-T1-E1-H1. The infection source was not known exactly but it must be considered infection from swine.

An Outbreak Associated with Sapovirus GI.3 in an Elementary School in Gyeonggi-do, Korea

On October 4, 2018, an outbreak of gastroenteritis associated with sapovirus occurred among elementary school students in Gyeonggi-do, Korea. Epidemiologic studies were conducted in a retrospective cohort approach. Using self-administered questionnaires, we collected information on symptoms and food items consumed. Of the 999 subjects, 17 developed patients that met the case definition. The main symptom was vomiting (100%), and the symptomatic age was 6-12 years. Positive samples were identified by conventional reverse transcription polymerase chain reaction for sequencing. They were classified into genotype GI.3 by phylogenetic analysis. This is the first report of an outbreak associated with sapovirus GI.3 in Korea.

Entropy production and fluctuation theorems on complex networks

Entropy production (EP) is a fundamental quantity useful for understanding irreversible process. In stochastic thermodynamics, EP is more evident in probability density functions of trajectories of a particle in the state space. Here, inspired by a previous result that complex networks can serve as state spaces, we consider a data packet transport problem on complex networks. EP is generated owing to the complexity of pathways as the packet travels back and forth between two nodes along the same pathway. The total EPs are exactly enumerated along all possible shortest paths between every pair of nodes, and the functional form of the EP distribution is proposed based on our numerical results. We confirm that the EP distribution satisfies the detailed and integral fluctuation theorems. Our results should be pedagogically helpful for understanding trajectory-dependent EP in stochastic processes and exploring nonequilibrium fluctuations associated with the entanglement of dividing and merging among the shortest pathways in complex networks.

A Compressed-Sensing Based Blind Deconvolution Method for Image Deblurring in Dental Cone-Beam Computed Tomography

In cone-beam computed tomography (CBCT), reconstructed images are inherently degraded, restricting its image performance, due mainly to imperfections in the imaging process resulting from detector resolution, noise, X-ray tube's focal spot, and reconstruction procedure as well. Thus, the recovery of CBCT images from their degraded version is essential for improving image quality. In this study, we investigated a compressed-sensing (CS)-based blind deconvolution method to solve the blurring problem in CBCT where both the image to be recovered and the blur kernel (or point-spread function) of the imaging system are simultaneously recursively identified. We implemented the proposed algorithm and performed a systematic simulation and experiment to demonstrate the feasibility of using the algorithm for image deblurring in dental CBCT. In the experiment, we used a commercially available dental CBCT system that consisted of an X-ray tube, which was operated at 90 kV_p and 5 mA, and a CMOS flat-panel detector with a 200-μm pixel size. The image characteristics were quantitatively investigated in terms of the image intensity, the root-mean-square error, the contrast-to-noise ratio, and the noise power spectrum. The results indicate that our proposed method effectively reduced the image blur in dental CBCT, excluding repetitious measurement of the system's blur kernel.

Chemical stability of morphine and methadone, and of methadone in combination with acepromazine, medetomidine or xylazine, during prolonged storage in syringes

OBJECTIVE

To assess the chemical and physical stability of morphine and methadone stored in syringes for 12 months and of methadone when mixed with acepromazine, medetomidine or xylazine.

METHODS

A high-performance liquid chromatography (HPLC) technique was developed and validated for the analysis of morphine and methadone. Morphine and methadone were dispensed into syringes and stored at 25°C/60% relative humidity (RH) and 40°C/75% RH. Solutions containing mixtures of methadone combined with acepromazine, medetomidine or xylazine were stored in syringes at 25°C/60%RH. At initiation, after 1 week and then 1, 3, 6, 9 and 12 months, samples were analysed by HPLC for the quantification of the morphine or methadone. Measured concentrations were assessed as a function of storage time and temperature using linear regression statistics to calculate stability.

RESULTS

When stored at 40°C/75%RH as pre-dispensed syringes, severe physical and chemical changes were observed after the third month for both morphine and methadone. In contrast, at 25°C/60%RH both drugs remained chemically stable for 12 months, with concentration variations not exceeding a 5% change from initiation as stipulated in VICH stability guidelines. When in combination with acepromazine or xylazine, methadone also remained chemically stable, but the combination with medetomidine failed stability criteria prior to 6 months. Precipitation compromised the physical stability of methadone in all unsealed syringes prior to 9 months' storage.

CONCLUSION

Pre-dispensing morphine or methadone into unsealed syringes compromises the drugs' physical stability. Mixing of methadone with other drugs can degrade its chemical stability.

Serum 25-hydroxyvitamin D cutoffs for functional bone measures in postmenopausal osteoporosis

This study sought to determine the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health in postmenopausal women with low bone mass. A serum 25(OH)D concentration of 20 ng/mL rather than 30 ng/mL was appropriate for bone health.

INTRODUCTION

There is no consensus on the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health. The aim of this study was to investigate the relationship between 25(OH)D measured via liquid chromatography-mass spectrometry (LC-MS/MS), which is the current gold standard, and biochemical markers of bone turnover, PTH, and bone mineral densitometry (BMD).

METHODS

The medical records of 750 postmenopausal women newly diagnosed with osteoporosis or osteopenia at Samsung Medical Center from 2009 to 2014 were investigated. Subjects were divided into four groups according to serum 25(OH)D concentration: <10, 10-20, 20-30, and ≥30 ng/mL. Serum concentrations of bone-specific alkaline phosphatase (BS-ALP), carboxy-terminal cross-linking telopeptide of type 1 collagen (CTx), intact PTH (iPTH), and BMD were compared among the four groups using analysis of covariance. Thresholds of 25(OH)D were then assessed using spline plots and locally weighted regression smoothing (LOESS) plots.

RESULTS

25(OH)D was negatively correlated with serum BS-ALP, CTx, and iPTH. Only femur neck and total femur BMD had significant positive relationships with 25(OH)D. Cutoff values of 11.9 and 9.7 ng/mL were estimated from the spline plots of femur neck and total femur BMD, respectively. For iPTH, the LOESS plot showed a steep decrease to a serum 25(OH)D concentration of about 20 ng/mL, followed by a plateau.

CONCLUSIONS

According to this study, a serum 25(OH)D concentration of 20 ng/mL, rather than 30 ng/mL, was appropriate for bone health.

Alzheimer's disease with cerebrovascular disease: current status in the Asia-Pacific region

BACKGROUND

There is growing awareness of the coexistence of Alzheimer's disease and cerebrovascular disease (AD+CVD), however, due to lack of well-defined criteria and treatment guidelines AD+CVD may be underdiagnosed in Asia.

METHODS

Sixteen dementia specialists from nine Asia Pacific countries completed a survey in September 2014 and met in November 2014 to review the epidemiology, diagnosis and treatment of AD+CVD in Asia. A consensus was reached by discussion, with evidence provided by published studies when available.

RESULTS

AD accounts for up to 60% and AD+CVD accounts for 10-20% of all dementia cases in Asia. The reasons for underdiagnosis of AD+CVD include lack of awareness as a result of a lack of diagnostic criteria, misdiagnosis as vascular dementia or AD, lack of diagnostic facilities, resource constraints and cost of investigations. There is variability in the tools used to diagnose AD+CVD in clinical practice. Diagnosis of AD+CVD should be performed in a stepwise manner of clinical evaluation followed by neuroimaging. Dementia patients should be assessed for cognition, behavioural and psychological symptoms, functional staging and instrumental activities of daily living. Neuroimaging should be performed using computed tomography or magnetic resonance imaging. The treatment goals are to stabilize or slow progression as well as to reduce behavioural and psychological symptoms, improve quality of life and reduce disease burden. First-line therapy is usually an acetylcholinesterase inhibitor such as donepezil.

CONCLUSION

AD+CVD is likely to be under-recognised in Asia. Further research is needed to establish the true prevalence of this treatable and potentially preventable disease.

Comparison of Total Arch and Partial Arch Transposition During Hybrid Endovascular Repair for Aortic Arch Disease

OBJECTIVE

Total arch transposition (TAT) during hybrid endovascular repair for aortic arch disease is believed to allow a better landing zone, but also to be associated with higher peri-operative mortality than partial arch transposition (PAT). Information on this issue is limited.

METHOD

This study was a retrospective analysis. All 53 consecutive patients with aortic arch disease (41 males, mean age 65.0 years) who underwent hybrid endovascular repair with TAT (zone 0, n=20) or PAT (zone 1 or 2, n=33) from 2008 to 2014 were analyzed retrospectively. The peri-operative and late outcomes of these two groups were compared.

RESULTS

Baseline characteristics, including EuroSCORE II results, were similar in the two groups. After procedures, peri-operative mortalities and stroke rates were similar in the two groups (5.0% vs. 9.1%, p=1.000, and 10.0% vs. 6.1%, p=.627). Interestingly, all four strokes occurred in patients with a type III aortic arch irrespective of transposition type. Primary success rates (80.0% vs. 69.7%, p=.527) and type I endoleak incidences (20.0% vs. 27.3%, p=.744) were not significantly different. During follow up (mean duration 36.9 months), overall survival (89.7% vs. 87.4% at 1 year and 89.7% vs. 79.3% at 3 years; p=.375) and re-intervention free survival rates (78.6% vs. 92.0% at 1 year; 72.0% vs. 62.2% at 3 years, p=.872) were similar in the two groups.

CONCLUSION

Morbidity and mortality were high within the first year of hybrid endovascular therapy for aortic arch disease, implying that candidates for hybrid procedures need to be selected carefully. Hybrid endovascular repair with TAT was found to have peri-operative mortality, stroke, and long-term survival rates comparable with PAT, so hybrid endovascular repair may be considered, irrespective of type of arch reconstruction, when clinically indicated.

Clinical Applications of Simultaneous PET/MR Imaging Using (R)-[11C]-Verapamil with Cyclosporin A: Preliminary Results on a Surrogate Marker of Drug-Resistant Epilepsy

BACKGROUND AND PURPOSE

The development of resistance to antiepileptic drugs is explained well by the transporter hypothesis, which suggests that drug resistance is caused by inadequate penetration of drugs into the brain barrier as a result of increased levels of efflux transporter such as p-glycoprotein. To evaluate the brain expression of p-glycoprotein in patients with drug-resistant epilepsy, including neocortical epilepsy, we developed a noninvsive quantitative analysis including asymmetry indices based on (R)-[(11)C]-verapamil PET/MR imaging with cyclosporin A, a p-glycoprotein inhibitor.

MATERIALS AND METHODS

Six patients with drug-resistant epilepsy, 5 patients with drug-sensitive epilepsy, and 8 healthy controls underwent dynamic (R)-[(11)C]-verapamil PET/MR imaging with an intravenous infusion of cyclosporin A. Asymmetry indices [(Right Region - Left Region)/(Right Region + Left Region) × 200%] of the standard uptake values in each of the paired lobes were calculated.

RESULTS

All patients with drug-resistant epilepsy had significantly different asymmetry from the healthy controls, whereas all patients with drug-sensitive epilepsy had asymmetry similar to that in healthy controls. In the temporal lobe, the asymmetry indices of patients with left temporal lobe drug-resistant epilepsy were more positive than those of healthy controls (healthy controls: 4.0413 ± 1.7452; patients: 7.2184 ± 1.8237; P = .048), and those of patients with right temporal drug-resistant epilepsy were more negative (patients: -1.6496 ± 3.4136; P = .044). In addition, specific regions that had significant asymmetry were different between the lateral and medial temporal lobe epilepsy groups. In the frontal lobe, the asymmetry index of patients with right frontal lobe drug-resistant epilepsy was more negative than that in healthy controls.

CONCLUSIONS

We confirmed that statistical parametric mapping analysis by using asymmetry indices of (R)-[(11)C]-verapamil PET/MR imaging with cyclosporin A could be used as a surrogate marker for drug-resistant epilepsy, and this approach might be helpful for localizing or lateralizing the epileptic zone.

A purse-string suture at the level of internal inguinal ring, taking only the peritoneum leaving the distal sac: is it enough for inguinal hernia in pediatric patients?

PURPOSE

Although laparoscopic surgery in children has expanded in recent years. Laparoscopic hernia repair in children is still debatable. We aimed to summarize and describe our results of laparoscopic inguinal hernia repair and techniques among children.

METHODS

Between March 2011 and April 2013, 98 children (67 male, 31 female) underwent laparoscopic inguinal hernia repair at the department of surgery. The clinical outcomes were collected retrospectively.

RESULTS

The mean follow-up period was 22.6 months. Twelve patients were ex-premature infants and a contralateral patent processus vaginalis (PPV) was present in 37 of the 91 unilateral inguinal hernia patients. There were two postoperative complications (transient hydrocele, umbilical port site infection). The mean operative time was 46 min. Recurrence, metachronous hernia and testicular atrophy were not observed during the follow-up period.

CONCLUSIONS

Our preliminary experiences suggest that the laparoscopic purse-string suture of internal inguinal opening of hernia sac could be a safe, effective, and reliable alternative for management of pediatric inguinal hernia.

Edge contacts of graphene formed by using a controlled plasma treatment

Despite the fact that the outstanding properties of graphene are well known, the electrical performance of the material is limited by the contact resistance at the metal-graphene interface. In this study, we demonstrate the formation of "edge-contacted" graphene through the use of a controlled plasma processing technique that generates a bond between the graphene edge and the contact metal. This technique controls the edge structure of the bond and significantly reduces the contact resistance. This simple approach requires no additional post-processing and has been proven to be very effective. In addition, controlled pre-plasma processing was applied in order to produce CVD-graphene field effect transistors with an enhanced adhesion and improved carrier mobility. The contact resistance attained by using pre-plasma processing was 270 Ω μm, which is a decrease of 77%.

PPARγ induces growth inhibition and apoptosis through upregulation of insulin-like growth factor-binding protein-3 in gastric cancer cells

Peroxisome proliferator activator receptor-gamma (PPARγ) is a ligand-activated transcriptional factor involved in the carcinogenesis of various cancers. Insulin-like growth factor-binding protein-3 (IGFBP-3) is a tumor suppressor gene that has anti-apoptotic activity. The purpose of this study was to investigate the anticancer mechanism of PPARγ with respect to IGFBP-3. PPARγ was overexpressed in SNU-668 gastric cancer cells using an adenovirus gene transfer system. The cells in which PPARγ was overexpressed exhibited growth inhibition, induction of apoptosis, and a significant increase in IGFBP-3 expression. We investigated the underlying molecular mechanisms of PPARγ in SNU-668 cells using an IGFBP-3 promoter/luciferase reporter system. Luciferase activity was increased up to 15-fold in PPARγ transfected cells, suggesting that PPARγ may directly interact with IGFBP-3 promoter to induce its expression. Deletion analysis of the IGFBP-3 promoter showed that luciferase activity was markedly reduced in cells without putative p53-binding sites (-Δ1755, -Δ1795). This suggests that the critical PPARγ-response region is located within the p53-binding region of the IGFBP-3 promoter. We further demonstrated an increase in PPARγ-induced luciferase activity even in cells treated with siRNA to silence p53 expression. Taken together, these data suggest that PPARγ exhibits its anticancer effect by increasing IGFBP-3 expression, and that IGFBP-3 is a significant tumor suppressor.

Optimal formation of genetically modified and functional pancreatic islet spheroids by using hanging-drop strategy

BACKGROUND

Rejection and hypoxia are important factors causing islet loss at an early stage after pancreatic islet transplantation. Recently, islets have been dissociated into single cells for reaggregation into so-called islet spheroids. Herein, we used a hanging-drop strategy to form islet spheroids to achieve functional equivalence to intact islets.

METHODS

To obtain single islet cells, we dissociated islets with trypsin-EDTA digestion for 10 minutes. To obtain spheroids, we dropped various numbers of single cells (125, 250, or 500 cells/30 μL drop) onto a Petri dish, that was inverted for incubation in humidified air containing 5% CO(2) at 37 °C for 7 days. The aggregated spheroids in the droplets were harvested for further culture.

RESULTS

The size of the aggregated islet spheroids depended on the number of single cells (125-500 cells/30 μL droplet). Their morphology was similar to that of intact islets without any cellular damage. When treated with various concentrations of glucose to evaluate responsiveness, their glucose-mediated stimulation index value was similar to that of intact islets, an observation that was attributed to strong cell-to-cell interactions in islet spheroids. However, islet spheroids aggregated in general culture dishes showed abnormal glucose responsiveness owing to weak cell-to-cell interactions. Cell-to-cell interactions in islet spheroids were confirmed with an anti-connexin-36 monoclonal antibody. Finally, nonviral poly(ethylene imine)-mediated interleukin-10 cytokine gene delivered beforehand into dissociated single cells before formation of islet spheroids increased the gene transfection efficacy and interleukin-10 secretion from islet spheroids >4-fold compared with intact islets.

CONCLUSION

These results demonstrated the potential application of genetically modified, functional islet spheroids with of controlled size and morphology using an hanging-drop technique.

The contributions of MRI-based measures of gray matter, white matter hyperintensity, and white matter integrity to late-life cognition

BACKGROUND AND PURPOSE

GM volume, WMH volume, and FA are each associated with cognition; however, few studies have detected whether these 3 different types of MR imaging measurements exert independent or additive effects on cognitive performance. To detect their extent of contribution to cognitive performance, we explored the independent and additive contributions of GM atrophy, white matter injury, and white matter integrity to cognition in elderly patients.

MATERIALS AND METHODS

Two hundred and 9 elderly patients participated in the study: 97 were CN adults, 65 had MCI, and 47 had dementia. We measured GM on T1-weighted MR imaging, WMH on FLAIR, and FA on DTI, along with psychometrically matched measures of 4 domains of cognitive performance, including semantic memory, episodic memory, executive function, and spatial abilities.

RESULTS

As expected, patients with dementia performed significantly more poorly in all 4 cognitive domains, whereas patients with MCI performed generally less poorly than dementia patients, though considerable overlap in performance was present across groups. GM, FA, and WMH each differed significantly between diagnostic groups and were associated with cognitive measures. In multivariate models that included all 3 MR imaging measures (GM, WMH, and FA), GM volume was the strongest determinant of cognitive performance.

CONCLUSIONS

These results strongly suggest that MR imaging measures of GM are more closely associated with cognitive function than WM measures across a broad range of cognitive and functional impairment.

White matter tract abnormalities in first-episode psychosis

Fibers connecting fronto-temporal and fronto-medial structures that pass through the anterior limb of the internal capsule (ALIC) subserve executive and psychomotor functioning. Both of these functions are adversely affected in schizophrenia, and may be abnormal at illness onset. In a study of first-episode psychosis, we used diffusion tensor imaging (DTI) and cognitive testing to examine ALIC integrity. Fourteen early psychosis patients and 29 healthy volunteers were included. Symptoms were assessed with the Positive and Negative Syndromes Scale (PANSS). All structural and diffusion scans were acquired on a GE Signa 1.5T scanner. A T1-weighted 3D FSPGR Inversion Recovery imaging series was acquired for manual seeding in structural space. Diffusion tensor imaging (DTI) was performed, and all DTI images were co-registered to structural space. Seeds were manually drawn bilaterally on the coronal plane at a specified location. Diffusion images were post-processed for subsequent Tract-based Spatial Statistics (TBSS) analysis. First-episode psychosis patients had significantly smaller fronto-medial and fronto-temporal AIC tract volumes compared to healthy volunteers on the left and the right (p-values<0.04). No differences in mean fractional anisotropy (FA) were seen within either left or right tracts (p-values>0.05), nor did TBSS reveal any other differences in FA values between groups in other regions. Relationships between tract volumes and symptom severity were not observed in this study.

17α-hydroxlyase/17, 20-lyase deficiency in three siblings with primary amenorrhea and absence of secondary sexual development

BACKGROUND

17α-hydroxlyase/17, 20-lyase deficiency (17OHD) is a rare phenotype of congenital adrenal hyperplasia that can cause primary amenorrhea.

CASE

Three phenotypically female siblings visited the adolescent gynecologic clinic complaining of primary amenorrhea and absence of secondary sexual developments. All had constant high blood pressure and showed a hypergonadotropic hypogonadal state with high progesterone and low testosterone levels. Two were genotypically females and one was genotypically a male; all were confirmed to have 17OHD, and estrogen replacement, glucocorticoids, and antihypertensive drugs were Prescribed to the patients.

SUMMARY AND CONCLUSION

Identifying a 17OHD patient complaining of primary amenorrhea in a gynecologic clinic is important for proper management.

Hormonal differences between female kidney transplant recipients and healthy women with the same gynecologic conditions

BACKGROUND

End-stage renal disease is associated with severe abnormalities in reproductive function. However, the abnormalities are reversed by successful kidney transplantation. The aim of the present study was to compare hormonal levels between recipients with successful kidney transplantations and healthy women with the same gynecologic conditions.

METHODS

The study group consisted of 31 women of reproductive age with end-stage renal disease who underwent successful kidney transplantation. The ratio of the control group, composed of healthy woman, to the study group was 3:1 matched for age and symptoms.

RESULTS

Abnormal bleeding (n = 14) and infertility were the most common gynecologic conditions in kidney transplant recipients. The levels of estrogen (E2) and follicle-stimulating hormone (FSH) in the study group were higher than in the control group, but the levels of progesterone (P4) and luteinizing hormone (LH) were lower in the study group than in the control group. There were no significant differences in prolactin and thyroid-stimulating hormone between the two groups. The incidence of infertility in patients who receive steroid was higher than those with no steroid use (P = .007).

CONCLUSIONS

Compared with healthy age- and symptom-matched women, female kidney transplant recipients have increased levels of E2 and FSH and decreased levels of P4 and LH. These differences in hormone profiles may predispose kidney transplant recipients to increased risk of gynecologic pathologies.

Radiological response predicts survival following transarterial chemoembolisation in patients with unresectable hepatocellular carcinoma

BACKGROUND

It remains unclear whether initial compact lipiodol uptake after transarterial chemoembolisation (TACE) is associated with improved survival in patients with hepatocellular carcinoma (HCC).

AIM

To reveal the clinical relevance of compact lipiodolisation after TACE.

METHODS

We studied 490 patients with unresectable HCC who had first been treated with TACE. Compact lipiodolisation was defined as the absence of an arterial enhancing lesion, reflecting complete lipiodol uptake, as assessed by dynamic computed tomography (CT) 1 month after treatment. The rate of initial compact lipiodolisation was analysed according to multiplicity and size of tumour, and survival of patients who achieved compact lipiodolisation was compared to that of patients who did not.

RESULTS

Of the 490 patients, 409 (83.5%) were in Child-Pugh class A and 81 (16.5%) in class B. The rate of initial compact lipiodolisation in single HCCs was higher than that in multinodular HCCs (33.7% vs. 14.6%, P < 0.001). Among single HCCs, the rate of compact lipiodolisation in tumours ≤5, 5-10 and >10 cm was 46.6%, 13.6%, and 0% respectively. The 1-, 3- and 5-year survival rates of patients with compact uptake were 92.7%, 70.7% and 52.4% compared to 60.8%, 28.0% and 16.9% in patients with noncompact lipiodolisation. Multivariate analysis revealed that Child-Pugh class, alpha-fetoprotein level, tumour node metastasis stage, portal vein thrombosis and initial compact lipiodolisation were independent predictors of survival.

CONCLUSIONS

Initial compact lipiodol uptake after transarterial chemoembolisation is associated with improved survival in patients with unresectable hepatocellular carcinoma. Accordingly, initial complete lipiodolisation should be considered a relevant therapeutic target.

Conserved features of cancer cells define their sensitivity to HAMLET-induced death; c-Myc and glycolysis

HAMLET is the first member of a new family of tumoricidal protein-lipid complexes that kill cancer cells broadly, while sparing healthy, differentiated cells. Many and diverse tumor cell types are sensitive to the lethal effect, suggesting that HAMLET identifies and activates conserved death pathways in cancer cells. Here, we investigated the molecular basis for the difference in sensitivity between cancer cells and healthy cells. Using a combination of small-hairpin RNA (shRNA) inhibition, proteomic and metabolomic technology, we identified the c-Myc oncogene as one essential determinant of HAMLET sensitivity. Increased c-Myc expression levels promoted sensitivity to HAMLET and shRNA knockdown of c-Myc suppressed the lethal response, suggesting that oncogenic transformation with c-Myc creates a HAMLET-sensitive phenotype. Furthermore, HAMLET sensitivity was modified by the glycolytic state of tumor cells. Glucose deprivation sensitized tumor cells to HAMLET-induced cell death and in the shRNA screen, hexokinase 1 (HK1), 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 1 and hypoxia-inducible factor 1α modified HAMLET sensitivity. HK1 was shown to bind HAMLET in a protein array containing ∼8000 targets, and HK activity decreased within 15 min of HAMLET treatment, before morphological signs of tumor cell death. In parallel, HAMLET triggered rapid metabolic paralysis in carcinoma cells. Tumor cells were also shown to contain large amounts of oleic acid and its derivatives already after 15 min. The results identify HAMLET as a novel anti-cancer agent that kills tumor cells by exploiting unifying features of cancer cells such as oncogene addiction or the Warburg effect.

Percutaneous cryoablation of small hepatocellular carcinomas using a 17-gauge ultrathin probe

AIM

To evaluate the feasibility and safety of percutaneous cryoablation (PCA) of small hepatocellular carcinomas (HCCs) using a 17 G ultrathin cryoprobe.

MATERIALS AND METHODS

Twenty patients (male:female ratio14:6) with 20 HCCs, who were not surgical candidates, underwent ultrasound (US)-guided PCA for treatment of HCCs. Single HCCs less than 3cm in diameter were included in this study. Ablation was performed using a 17 G cryoprobe. The effectiveness was determined by the changes in alpha-foetoprotein level and degree of tumour necrosis on follow-up computed tomography (CT); complete response (100% necrosis), partial response (100%>necrosis≥30%), stable disease (any cases not qualifying for either partial response or progressive disease) and progressive disease (increase of at least 20% in diameter of viable tumour). Haemoglobin, white blood cell count (WBC), serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), and total bilirubin were compared before and after the procedure, and the technical feasibility, complications, clinical outcomes and survival of each patient were also evaluated.

RESULTS

All procedures were technically successful. Each patient complained of negligible pain and there was no other procedure-related complication or mortality. The mean level of alpha-foetoprotein declined significantly from 53.2 to 20.4ng/ml 1 month after the procedure (p<0.05). At 1-month follow-up CT, there were 13 complete responses, four partial responses, three patients with stable disease, and no patients had progressive disease. Six of seven lesions that did not present with a complete response underwent further treatment. On long-term follow up (6-30 months; mean 20.7), a local recurrence was seen in one of 13 lesions (8%) with complete response revealed. Laboratory findings showed no significant changes except for the transient increase of SGOT and SGPT.

CONCLUSION

US-guided PCA using a 17 G cryoprobe was feasible and safe for the treatment of HCC smaller than 3cm.

Decompression and interspinous dynamic stabilization using the locker for lumbar canal stenosis associated with low-grade degenerative spondylolisthesis

BACKGROUND

Decompression and spinal fusion have been generally recommended for spinal stenosis associated with low-grade degenerative spondylolisthesis (DS), although this is still controversial. The purpose of the present study is to analyze the clinical and radiological outcomes of interspinous dynamic stabilization using the Locker (WINNOVA co, Seoul, Korea) for lumbar canal stenosis with grade I DS.

METHODS

The authors performed a retrospective review of 23 consecutive patients who underwent single level decompression and the Locker application for lumbar canal stenosis with grade I DS and were followed up for at least 2 years. Excluded were those with DS grade II or higher and DS combined with foraminal disc herniation/stenosis. The mean age of patients at the time of surgery was 62.1 years (range: 45-81 years).

RESULTS

There were no complications in the perioperative period. At a mean follow-up duration of 28.3 months (range: 24-32 months), visual analogue scale scores for back pain, leg pain, and Oswestry disability index had decreased significantly; from 4.6, 7.2, and 38.5% to 2.4, 2.6, and 15.3%, respectively. Clinical success was achieved in 87% of the patients. The mean percentage of slippage did not change significantly. The mean sagittal rotation angle significantly decreased from 9.7 to 6.5 degrees (p=0.01). One patient (4.3%) underwent secondary fusion surgery due to persistent pain.

CONCLUSIONS

Decompression and interspinous dynamic stabilization using the Locker yielded favorable clinical and radiological outcomes for lumbar canal stenosis with grade I DS and could be an alternative for spinal fusion. However, further long-term follow-up studies are necessary.

Regional pattern of white matter microstructural changes in normal aging, MCI, and AD

OBJECTIVE

To cross-sectionally compare the regional white matter fractional anisotropy (FA) of cognitively normal (CN) older individuals and patients with mild cognitive impairment (MCI) and Alzheimer disease (AD), separately focusing on the normal-appearing white matter (NAWM) and white matter hyperintensities (WMH), and to test the independent effects of presumed degenerative and vascular process on FA differences.

METHODS

Forty-seven patients with AD, 73 patients with MCI, and 95 CN subjects received diffusion tensor imaging and vascular risk evaluation. To properly control normal regional variability of FA, we divided cerebral white matter into 4 strata as measured from a series of young healthy individuals (H1 = highest; H2 = intermediate high; H3 = intermediate low; H4 = lowest anisotropy stratum).

RESULTS

For overall cerebral white matter, patients with AD had significantly lower FA than CN individuals or patients with MCI in the regions with higher baseline anisotropy (H1, H2, and H3), corresponding to long corticocortical association fibers, but not in H4, which mostly includes heterogeneously oriented fibers. Vascular risk showed significant independent effects on FA in all strata except H1, which corresponds to the genu and splenium of the corpus callosum. Similar results were found within NAWM. FA in WMH was significantly lower than NAWM across all strata but was not associated with diagnosis or vascular risk.

CONCLUSIONS

Both vascular and Alzheimer disease degenerative process contribute to microstructural injury of cerebral white matter across the spectrum of cognitive ability and have different region-specific injury patterns.

Post-growth annealing effects of Mg doped GaAs epitaxial layers on microstructural and optical properties

The post-growth thermal annealing effects of Mg doped GaAs epitaxial layers on the microstructural and optical properties grown by molecular beam epitaxy (MBE) have been investigated. The properties of Mg doped GaAs are estimated after the process of rapid thermal annealing (RTA) in the temperature range of 600 approximately 750 degrees C. The photoluminescence (PL) peak position of as-grown sample blueshifted from 1.473 to 1.485 eV as well as the pronounced enhancement in PL intensity by annealing at 600 degrees C. In the sample grown at the temperature of T(s) = 475 degrees C, the full-width at half maximum (FWHM) of double crystal X-ray diffraction (DCXRD) decreased form 27 to 8 arcsec with increasing of annealing temperature (600 approximately 700 degrees C). The crystalline quality variation of Mg doped GaAs layers by RTA is greatly dependent upon the doping level.

An overview of lung transplantation in Korea

OBJECTIVE

Lung transplantation (LTx) is the only option for end-stage lung disease refractory to medical treatment. The program was slow to start in Korea; the first LTx was performed in July 1996. By October 2007, 25 lung and 7 heart-lung transplantations have been performed at 5 institutes, with the majority being performed at one center. The aim of this study was to improve the survival rate following LTx by analyzing the operative procedure and its complications.

METHODS

We performed a retrospective review of the medical records of 18 patients who underwent lung and heart-lung transplantations from July 1996 to October 2007 at a single institute. Operative mortality was excluded from the analysis of early and late complications.

RESULTS

There were 12 males and 6 females of mean age 46.2 +/- 11.5 years (range, 25-63 years). The indications for transplantation included pulmonary emphysema (n = 6), idiopathic pulmonary fibrosis (n = 3), lymphangioleiomyomatosis (n = 3), Eisenmenger's syndrome (n = 2), bronchiectasis (n = 2), primary pulmonary hypertension (n = 1), and primary graft dysfunction after a single lung transplantation (SLT; n = 1). Operations consisted of SLTs in 9 patients, bilateral sequential single lung transplantations (BSSLTs) in 8 patients, and a heart-lung transplantation (HLT) in 1 patient. Early complications were bleeding necessitating rethoracotomy, severe reperfusion injury, seizure, prolonged airleak, chylothorax, and pulmonary artery stenosis. Late complications consisted of cytomegalovirus infection, pulmonary tuberculosis, posttransplantation lymphoproliferative disease, gastric ulcer perforation, pneumothorax, chylothorax, empyema, and aspergillosis. There were 5 operative deaths due to intraoperative bleeding (n = 1), acute graft dysfunction (n = 2), and multiorgan failure (n = 2). Excluding the operative mortality, the mean survival period was 18.5 +/- 23.7 months (range, 3-87 months).

CONCLUSIONS

Clinical experience in recent years may have reduced complication rates and led to prolonged survival. Increasing the candidate list through better results and raising awareness of the LTx program is necessary to move forward with thoracic transplantation in Korea.

Spinous process splitting laminectomy for lumbar canal stenosis: a critical appraisal

Spinous process splitting laminectomy (SPSL) is a surgical technique for lumbar canal stenosis, which aims to preserve the paraspinal muscles. Twenty-five patients with lumbar canal stenosis who consecutively underwent SPSL from June 2005 to December 2005 were evaluated. Clinical outcomes were assessed using the visual analogue scale (VAS) scores and Oswestry disability index (ODI). Mean age of the patients at surgery was 62.6 years (range: 42-77 years). Seventeen patients underwent SPSL for single level stenosis, 4 for two levels, and 4 for three levels. In 10 patients, discectomy was simultaneously performed at the same level as SPSL. Of 23 patients (92%) followed for a 1-year period, VAS for back pain, leg pain, and ODI decreased significantly; from 4.8, 8.1, and 54.3-2.1, 2.7, and 23.1, respectively. However, a significant improvement (> 50% of their initial VAS/ODI score) of back pain, leg pain, and functional status was observed in only 65.2, 65.2, and 52.2%, respectively. Complications occurred in 4 patients (16%). Although SPSL for lumbar canal stenosis yielded relatively good clinical outcomes, the percentage of patients showing significant improvements in back pain, leg pain, and functional status were less than expected at one year after surgery.

Enhancement of protective immune responses by oral vaccination with Saccharomyces cerevisiae expressing recombinant Actinobacillus pleuropneumoniae ApxIA or ApxIIA in mice

We previously induced protective immune response by oral immunization with yeast expressing the ApxIIA antigen. The ApxI antigen is also an important factor in the protection against Actinobacillus pleuropneumoniae serotype 5 infection; therefore, the protective immunity in mice following oral immunization with Saccharomyces cerevisiae expressing either ApxIA (group C) or ApxIIA (group D) alone or both (group E) was compared with that in two control groups (group A and B). The immunogenicity of the rApxIA antigen derived from the yeast was confirmed by a high survival rate and an ApxIA-specific IgG antibody response (p < 0.01). The highest systemic (IgG) and local (IgA) humoral immune responses to ApxIA and ApxIIA were detected in group E after the third immunization (p < 0.05). The levels of IL-1beta and IL-6 after challenge with an A. pleuropneumoniae field isolate did not change significantly in the vaccinated groups. The level of TNF-alpha increased in a time-dependent manner in group E but was not significantly different after the challenge. After the challenge, the mice in group E had a significantly lower infectious burden and a higher level of protection than the mice in the other groups (p < 0.05). The survival rate in each group was closely correlated to the immune response and histopathological observations in the lung following the challenge. These results suggested that immunity to the ApxIA antigen is required for optimal protection.

Refracture after Ilizarov osteosynthesis in atrophic-type congenital pseudarthrosis of the tibia

We investigated patterns of refracture and their risk factors in patients with congenital pseudarthrosis of the tibia after Ilizarov osteosynthesis. We studied 43 cases in 23 patients. Temporal and spatial patterns of refracture and refracture-free survival were analysed in each case. The refracture-free rate of cumulative survival was 47% at five years and did not change thereafter. Refracture occurred at the previous pseudarthrosis in 16 of 19 cases of refracture. The risk of refracture was significantly higher when osteosynthesis was performed below the age of four years, when the tibial cross-sectional area was narrow, and when associated with persistent fibular pseudarthrosis. Refracture occurs frequently after successful osteosynthesis in these patients. Delaying osteosynthesis, maximising the tibial cross-sectional area and stabilising the fibula may reduce the risk of refracture.

The Severe Cognitive Impairment Rating Scale--an instrument for the assessment of cognition in moderate to severe dementia patients

BACKGROUND/AIMS

This study aimed to develop a brief, reliable and valid test for cognitive function of severely demented patients.

METHODS

We constructed the Severe Cognitive Impairment Rating Scale, which consisted of 11 items covering memory, language, visuospatial function, frontal function and orientation, and investigated its reliability and validity on 267 subjects [normal: 65, very mild Alzheimer's disease (AD): 42, mild AD: 58, moderate AD: 36, severe AD: 44, profound AD: 22].

RESULTS

The internal consistency obtained by Cronbach's coefficient alpha was 0.93. The interrater reliability and test-retest reliability in the moderately to severely impaired subjects with an MMSE score of <or=14 was 0.99 (p < 0.001) and 0.90 (p < 0.001), respectively. It showed significant correlation with Severe MMSE (r = 0.96, p < 0.01), MMSE (r = 0.86, p < 0.01) and Clinical Dementia Rating (r = -0.83, p < 0.01). It was robust to both the floor effect in the severe/profound stage of AD and the ceiling effect in the mild/moderate stage of AD. Exploratory factor analysis yielded 2 factors (automatic informational processing and controlled informational processing) accounting for 73.5% of the total variance.

CONCLUSIONS

The Severe Cognitive Impairment Rating Scale is a valid and reliable test for evaluating the cognitive function of advanced AD patients.

Chitosan microspheres containing Bordetella bronchiseptica antigens as novel vaccine against atrophic rhinitis in pigs

The immune-stimulating activities of Bordetella bronchiseptica antigens containing dermonecrotoxin (BBD) loaded in chitosan microspheres (CMs) have already been reported in vitro and in vivo with a mouse alveolar macrophage cell line (RAW264.7) and mice. Therefore, this study attempted to demonstrate the successful induction of mucosal immune responses after the intranasal administration of BBD loaded in CMs (BBD-CMs) in colostrum-deprived pigs. The BBD was introduced to the CMs using an ionic gelation process involving tripolyphosphate (TPP). Colostrum-deprived pigs were then directly immunized through intranasal administration of the BBD-CMs. A challenge with a field isolate of B. bronchiseptica was performed ten days following the final immunization. The BBD-specific IgG and IgA titers, evident in the nasal wash and serum from the vaccinated pigs, increased with time (p<0.05). Following the challenge, the clinical signs of infection were about 6-fold lower in the vaccinated pigs compared with the nonvaccinated pigs. The grades for gross morphological changes in the turbinate bones from the vaccinated pigs were also significantly lower than the grades recorded for the nonvaccinated pigs (p<0.001). Therefore, the mucosal and systemic immune responses induced in the current study would seem to indicate that the intranasal administration of BBD-CMs may be an effective vaccine against atrophic rhinitis in pigs.

Biofilm-forming associated genotypic and phenotypic characteristics of Staphylococcus spp. isolated from animals and air

Biological monitoring is performed to detect and analyze microorganisms that have continuously made an effort to survive in the environment. Of such microorganisms, Staphylococcus spp. is considered a common cause of nosocomial and environmental infections., Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMMs) are required for the adhesion and biofilm formation of Staphylococci. Thirty-six and thirty-five Staphylococci isolated from animals and air, respectively, were analyzed. Biofilm formation and ten MSCRAMM genes were investigated using Congo red agar, tissue culture plate methods, and PCR. Airborne isolates were shown to have higher adherence and stronger biofilm formation than those from animals. The prevalence of MSCRAMM genes from air isolates was also higher than those from animals. Of the genes, eno was mainly associated with biofilm formation in both animals and airborne isolates (P<0.05). Moreover, the rate of airborne isolates harboring the eno gene was higher than in animal isolates. These results indicated that analysis of MSCRAMM genes with a phenotypic assay might be a helpful bacterial control system for the environment.

A normative study of the Revised Hasegawa Dementia Scale: comparison of demographic influences between the Revised Hasegawa Dementia Scale and the Mini-Mental Status Examination

BACKGROUND/AIMS

We investigated the demographic influence on the performance of the Revised Hasegawa Dementia Scale (HDS-R) and provided normative data of the HDS-R in the elderly.

METHODS

The HDS-R was administered to 803 community-dwelling cognitively normal elderly subjects aged 55 years or over. Cognitive disorders and psychiatric disorders were strictly excluded using the CERAD-K assessment packet and the Mini-International Neuropsychiatric Interview. The demographic influence on the performance of the HDS-R was examined using multiple linear regression analyses, and compared with that on the performance of the Mini-Mental Status Examination (MMSE) using the Chow test and t statistics. Overlapping strata were used in developing age-, education- and gender-specific normative data of the HDS-R.

RESULTS

Age, education, and gender influenced significantly the performance of the HDS-R, and explained 22.5% of the total score variance. Older age, lower education, and male gender were associated with lower performance of the HDS-R. However, the demographic influence on the HDS-R was much weaker than that on the MMSE (t = 5.578, d.f. = 800, p < 0.001). The normative data of the HDS-R stratified by age (60-69, 70-79, > or =80), education (0-6, 7-12, > or =13), and gender were presented.

CONCLUSIONS

The HDS-R was more robust to demographic influences than the MMSE, and normative data may contribute to improving further its diagnostic accuracy for dementia.

Identification of quorum sensing-related regulons in Vibrio vulnificus by two-dimensional gel electrophoresis and differentially displayed reverse transcriptase PCR

Vibrio vulnificus is thought to employ a quorum-sensing system to control the expression of a global gene. In this study, proteomes and transcriptomes of a lacZ null mutant, VvSR Delta Z, and a luxS-smcR double mutant, VvSR Delta ZSR, were compared with the parent strain, VvAR, by means of two-dimensional gel electrophoresis (2D-PAGE) and differentially displayed reverse transcriptase PCR (DDRT-PCR). 2D-PAGE analysis showed that 36 protein spots were differentially expressed, 14 of which have been identified by peptide-mass fingerprinting. The expression of eight cellular proteins was repressed by luxS and smcR mutation: Zn-dependent protease, 6-phosophofructokinase, periplasmic ABC-type Fe3(+) transport system, deoxyribose-phosphate aldolase, phosphomannomutase, orotidine-5'-phosphate decarboxylase, uridylate kinase, and an unidentified protein. These proteins are involved in virulence, adaptation to environmental stress, biosynthesis of LPS, and cell multiplication. Phage shock protein A, a chemotaxis signal transduction protein, and an uncharacterized low-complexity protein were activated in the cellular components of the luxS-smcR mutant. However, only three proteins, of unknown function, were identified in the extracellular components of the mutants. Analysis of transcriptomes with DDRT-PCR showed that two genes, phosphoribosylformylglycinamidine synthase and ATP-dependent protease HslVU protease were regulated at the transcriptional level by luxS and smcR gene mutation. The results from this study show conclusively that luxS/smcR quorum sensing endows a global change in gene expression to V. vulnificus.

Pluronic® F127 enhances the effect as an adjuvant of chitosan microspheres in the intranasal delivery of Bordetella bronchiseptica antigens containing dermonecrotoxin

We have studied a vaccine delivery system in vitro and in vivo based on chitosan microspheres (CMs) prepared in the presence of selected immunomodulators, Pluronic block copolymer F127 (F127). The Bordetella bronchiseptica multiple antigens containing dermonecrotoxin (BBD), a virulent factor leading to atrophic rhinitis (AR) in swine was loaded in CMs/F127 or CMs alone. The microspheres, prepared using an ionic gelation process with tripolyphosphate, demonstrated release profiles that showed a greater amount of BBD being released from BBD-loaded CMs/F127 (BBD-CMs/F127). In vitro experiments using mouse alveolar macrophage cells (RAW 264.7) demonstrated that BBD-CMs/F127 have significantly higher immune-stimulating activities than controls. The highest immune-stimulating activities by the BBD-CMs/F127 using RAW 264.7 cells were mirrored in the in vivo studies following nasal administration to mice. The mice immunized with BBD-CMs/F127 showed higher BBD specific IgA antibody responses in nasal wash, saliva and serum than mice immunized with BBD-CMs alone. Protective immunity was measured by survival rate after challenge with B. bronchiseptica via the nasal cavity. The survival rate of the group treated with BBD-CMs/F127 was higher than those of other groups. These results suggested that CMs/F127 represents a novel mucosal delivery system and that F127 could enhance the delivery of BBD-CMs in the vaccination scheme.

Depression in vascular dementia is quantitatively and qualitatively different from depression in Alzheimer's disease

BACKGROUND/AIMS

To compare the prevalence and characteristics of depression in vascular dementia (VaD) and Alzheimer's disease (AD) after adjusting for dementia severity and gender.

METHODS

One hundred and eight pairs of VaD and AD patients matched for dementia severity and gender were assessed.

RESULTS

Major depressive disorder (MDD) was more prevalent in the VaD group than in the AD group (20.4% in VaD, 10.2% in AD, p = 0.04, Cochran-Mantel-Haenszel, CMH, test) regardless of the dementia severity and gender. The odds ratio for developing MDD in the VaD group versus the AD group was estimated to be 2.20 (95% confidence interval = 1.02-4.74). Neurovegetative symptoms such as 'felt tired and weak all the time' (30.6% in VaD, 13.9% in AD, p = 0.003, CMH test) and 'changed weight without trying' (16.7% in VaD, 6.5% in AD, p = 0.02, CMH test) were more prevalent in the VaD group than in the AD group.

CONCLUSION

Depression in VaD was quantitatively and qualitatively different from that in AD regardless of the severity of dementia and gender; depression was more prevalent, severer and more retarded and vegetative in VaD than in AD.

Novel Approach to Performing Metabolite Identification in Drug Metabolism

A novel online method is developed, using liquid chromatography (LC)-accurate radioisotope counting dynamic-flow (ARC) coupled with a radioactivity detector and mass spectrometer, for metabolite identification in drug discovery and development. This method offers the advantages of improved sensitivity for detecting radiolabeled drugs as well as streamlining the process of identifying and characterizing metabolites. For the purposes of evaluating this method, in vitro human liver microsomal incubations with [(14)C]dextromethorphan are conducted. Online separation and identification of [(14)C]dextromethorphan metabolites are achieved without intensive sample preparation, concentration, or fraction collection. Mass spectrometric analysis identified and characterized the metabolites of dextromethorphan formed by N - and O -dealkylation, correlated well with previously published results. Chromatographic peaks for [(14)C]dextromethorphan and its metabolites are collected online, then infused for extended periods of time at a flow rate of 10 microL/min while maintaining the column pressure. The continuous analytical signal input allowed acquisition of a higher order of multistage fragmentation for both major and minor metabolites. The multistage MS fragmentation pattern obtained for the metabolites allowed defining the sites of metabolism for dextromethorphan. Further evaluations of this method are also conducted using a [(14)C]compound A to check the linearity and sensitivity of the dynamic-flow method. The R(2) value is 0.996 for the dynamic-flow method between 50 and 600 disintegrations per minute (dpm); the limit of detection for LC-ARC is 20 dpm, which is approximately 10 times more sensitive than conventional continuous-flow radioactivity detection techniques. The overall results suggest that the combination of LC-ARC with radioactivity detection and mass spectrometry has great potential as a powerful tool for enhancing the sensitivity of radioisotope measurement in metabolite identification studies during drug discovery and development.

Amphiphilic triblock copolymer poly(p-dioxanone-co-L-lactide)-block-poly(ethylene glycol), enhancement of gene expression and inhibition of lung metastasis by aerosol delivery

We describe the development of an aerosol system for topical gene delivery to the lungs of C57BL/6 mice. This system is based on the combination of the commercial cationic lipid Lipofectin with a novel amphiphilic triblock copolymer, poly(p-dioxanone-co-L-lactide)-block-poly(ethylene glycol) (PPDO/PLLA-b-PEG, and abbreviated in the text as polymeric micelles). After optimizing conditions for DNA delivery to the lungs of mice using the combination of polymeric micelles with Lipofectin and LacZ DNA, we used the Lipofectin/polymeric micelle system to deliver the tumor suppressor gene PTEN to the lungs of C57BL/6 mice bearing the B16-F10 melanoma. Lipofectin/PTEN/polymeric micelles significantly improved gene expression of PTEN in the lungs of mice with no evidence of cell toxicity or acute inflammation. Importantly, lung metastasis, as measured by lung weight, was significantly reduced (P<0.001), as were total tumor foci in the lungs (P<0.001) and size of individual tumor nodules in animals treated with Lipofectin/PTEN/polymeric micelles compared with control animals. Survival time was also extended. These results suggest that the Lipofectin/polymeric micelle system is appropriate for enhancing gene delivery in vivo and that it can be applied as a non-invasive gene therapy for lung cancer.

Minimization of immunosuppressive therapy after islet transplantation: combined action of heme oxygenase-1 and PEGylation to islet

We previously established a type of PEGylated islets to attenuate cellular immune reactions by immobilizing polyethylene glycol (PEG) molecules on islet surfaces, thereby synergistically reducing the dose of immunosuppressant cyclosporine A (CsA; 3 mg/kg/day) to protect transplanted islets. However, higher doses of immunosuppressants should be administered after islet transplantation due to nonspecific inflammation. This study documents that PEGylated islets can be cooperatively protected by the systemic overexpression of heme oxygenase-1 (HO-1), which has a potent cytoprotective function in preventing nonspecific inflammation during an early stage following islet transplantation. Under this scheme, the viability of PEGylated islets was improved; that is, PEG molecules could block cellular immunity and HO-1 could exert its cytoprotective property against inflammation. Interestingly, when employed with a low dose of CsA (1 mg/kg/day), a cooperative action of PEG molecules and HO-1 in immune reactions could result in the complete survival of transplanted islets for 100 days without islet function impairment. However, unmodified islets (control) were completely rejected within 2 weeks despite cotreatment with HO-1 expression and CsA. These results demonstrated that the combinatorial protocol of initial induction of HO-1 expression, followed by the daily administration of a low dose CsA after transplantation of PEGylated islets can be employed as a successful cell therapy in clinical islet transplantation.

In vivo induction of mucosal immune responses by intranasal administration of chitosan microspheres containing Bordetella bronchiseptica DNT

In vitro immune-stimulating activities of Bordetella bronchiseptica dermonecrotoxin (BBD)-loaded in chitosan microspheres (CMs) were reported with a mouse alveolar macrophage cell line (RAW264.7). Based on the report, in vivo activity of immune-induction was investigated by intranasal administration of the BBD-loaded CMs into mice. BBD was loaded into the CMs prepared by an ionic gelation process with tripolyphosphate. Mice were immunized by direct administration of the BBD-loaded CMs into the nasal cavity. After immunization of the mice, BBD-specific immune responses (IgG and IgA titers) were measured in sera, nasal wash, and saliva by ELISA. BBD-specific IgA titers in the nasal cavity were time- and dose-dependently increased by the administration. Similar phenomena were observed in the analysis of systemic IgA and IgG in sera. However, the antibody in saliva was undetectable by ELISA. These results suggested that direct vaccination via the nasal cavity was effective for targeting nasal-associated lymphoid tissues, and that CMs were an efficient adjuvant in nasal mucosal immunity for atrophic rhinitis vaccine.

The influence of facet tropism on herniation of the lumbar disc in adolescents and adults

We carried out a study to determine the effect of facet tropism on the development of adolescent and adult herniation of the lumbar disc. We assessed 149 levels in 140 adolescents aged between 13 and 18 years and 119 levels in 111 adults aged between 40 and 49 years with herniation. The facet tropism of each patient was measured at the level of the herniated disc by CT. There was no significant difference in facet tropism between the herniated and the normal discs in both the adolescent and adult groups, except at the L4-L5 level in the adults. Facet tropism did not influence the development of herniation of the lumbar disc in either adolescents or adults.

Development and use of a multiplex polymerase chain reaction assay based on Apx toxin genes for genotyping of Actinobacillus pleuropneumoniae isolates

Actinobacillus pleuropneumoniae (A. pleuropneumoniae) is the etiological agent of a porcine pleuropneumonia that threatens the global swine industry. The major pathogenic toxins of A. pleuropneumoniae include ApxI, ApxII, ApxIII, and ApxIV, which are serotype or serovar specific. Several techniques have been developed for the identification and typing of A. pleuropneumoniae. Serological assays are used to identify and serotype A. pleuropneumoniae, but factors such as cross-reactivity limit their specificity. Labor, time, and the requirement for specific antibodies are also drawbacks of these assays. Multistep polymerase chain reaction (PCR) techniques based on apx genes have been reported for the identification and typing of A. pleuropneumoniae. This study developed multiplex PCR for the identification and genotyping of A. pleuropneumoniae based on apx genes. This multiplex PCR technique was successful in differentiating 11 of 15 reference serotypes. Five different primer sets were used to amplify the 4 apx genes from each serotype in a single-step reaction. The multiplex PCR reported in this study was further used in genotyping 51 field isolates of A. pleuropneumoniae from different regions of Korea. The concomitant amplification of all 4 apx genes makes multiplex PCR more specific and convenient for the diagnosis and genotyping of A. pleuropneumoniae.

Tob is a potential marker gene for the basal layer of the epidermis and is stably expressed in human primary keratinocytes

BACKGROUND

Epidermis consists of multiple layers, from the proliferating basal layer to terminal differentiated cornified layers, and these layers are defined by differentiation status. Tob gene product is known to be a member of the BTG antiproliferative protein family. We investigated the expression pattern of Tob gene product to understand the possible role in differentiation of keratinocytes and epidermis.

OBJECTIVES

In this study, we examined the expression of Tob gene product in the primary cultured human keratinocytes and in the in vivo epidermis.

METHODS

The expression of Tob gene product was assessed by Western blotting analysis. Cellular localization of Tob was detected using the green fluorescent protein-tagged Tob cDNA expression construct. In vivo expression of Tob gene product in the epidermis was determined by immunohistochemistry with paraffin sections.

RESULTS

Tob family members are degraded by the ubiquitine-proteasome system triggered by the growth signal. Tob is stably and abundantly expressed in primary cultured human keratinocytes. Furthermore, the expression of Tob in the keratinocytes persists during the differentiation induced by calcium; however, it was not detected in primary cultured fibroblasts. Also, the subcellular localization of Tob is mainly in the cellular membrane in the primary human keratinocytes. We evaluated Tob expression in normal skin, oral mucosa and different diseases, such as psoriasis, X-linked ichthyosis and squamous cell carcinoma (SCC). Using immunohistochemical analysis, we observed that Tob was selectively expressed in the basal layer of X-linked ichythyosis and the hyperproliferative basal layer of psoriasis and oral mucosa as well as in normal epidermis. In SCC, the expression of Tob gene product was relatively decreased.

CONCLUSIONS

Tob is stably expressed in primary human keratinocytes and it is specifically expressed in the basal layer of in vivo epidermis.