Phenotypic traits, virulence-associated gene profile and genetic relatedness of Edwardsiella tarda isolates from Japanese eel Anguilla japonica in Korea.

UNLABELLED: Edwardsiella tarda is the predominant bacterium in farm-cultured eel in Korea. Here, we evaluated the heterogeneity of 37 E. tarda isolates derived from Japanese eel with various origins (olive flounder, common carp and ornamental fish) between 2003 and 2010. Regardless of origins, the biochemical characteristics of E. tarda isolates were homogenous except hydrogen sulfide production, citrate utilization and mannitol fermentation. Based on the phylogenetic analysis of 16S rRNA, E. tarda isolates could be classified into two subgroups and displayed a close relation with Edwardsiella ictaluri and Edwardsiella hosinae lineages, suggesting that the subgroup I has been a predominant type in the Jeonnam and Jeonbuk provinces. I-CeuI-based pulsed-field gel electrophoresis (PFGE) typing showed that the isolates from Japanese eels belonged to 11 pulsotypes, indicating that the presence of highly genomic diversity. Additionally, two isolates, ET-060 and ET-191, showed a high frequency of virulence genes (100%) and caused 90% and 60% mortality in Japanese eel, respectively. This finding suggests a substantial congruence of virulence gene profiles and pathogenicity. Our results demonstrate that the intraspecific diversity within E. tarda strains from Japanese eel has been in prior existence. SIGNIFICANCE AND IMPACT OF THE STUDY: Based on the biochemical characteristics, the phylogenetic property of the 16S rRNA gene and PFGE types of Edwardsiella tarda, we could identify the intraspecific diversity of isolates from Japanese eel, Anguilla japonica in Korea. In addition, this study describes the strong congruence of virulence-related genes and pathogenicity, suggesting that the virulence profile may be useful tool for prediction of pathogenicity.

The susceptibility of magpies to a highly pathogenic avian influenza virus subtype H5N1.

Korean wild magpies (Pica pica sericea) were intranasally inoculated with highly pathogenic avian influenza (A/Chicken/Korea/ES/03 virus) (H5N1), which was classified as clade 2.5. We estimated viral replication, death after infection, and histology and immunohistochemistry. This species was highly susceptible to severe infection; 100% of birds died within 5 to 8 d. The virus was detected from oropharyngeal (1 to 5 d postinfection) and cloacal (3 to 5 d postinfection) swabs from infected magpies. At necropsy, the prominent lesions were coalescing necrosis of the pancreas with enlargement of livers and spleens. Microscopically, pancreas, brain, heart, adrenal gland, and kidney were most consistently affected with necrotic and inflammatory changes, and viral antigen was frequently demonstrated in the parenchyma of these organs. As a result, Korean wild magpies were very susceptible to avian influenza (H5N1) virus.

Development of a stabilizer for lyophilization of an attenuated duck viral hepatitis vaccine.

The live attenuated vaccine against duck viral hepatitis currently available in Korea requires special freezers for storage and transportation with extra costs involved. The development of a lyophilization stabilizer for live attenuated duck viral hepatitis virus (DHV) vaccines, therefore, has been highly recommended for the wider application of the vaccines. Four conventional vaccine stabilizer formulations containing a disaccharide, such as lactose, trehalose, or sucrose, and new formulations containing sorbitol were tested for their efficacy in stabilizing a new attenuated DHV type 3 vaccine candidate under different storage temperatures, 4 and 37 degrees C. The vaccine virus and each stabilizer formulation were combined and submitted to lyophilization and the viability of the virus was measured in 7-d-old specific-pathogen-free chicken embryos by determining the 50% egg lethal dose. Stabilizer formulations containing 2, 4, or 8% sorbitol preserved the viability of the vaccine virus much better than the other stabilizer formulations and 2% sorbitol was the optimal concentration in a standard stabilizing buffer, phosphate glutamate gelatin (0.0038 M KH2PO4, 0.0071 M K2HPO4, 0.0049 M monosodium L-glutamate, and 0.5% gelatin). The results demonstrate that the stabilizer formulation containing 2% sorbitol and 0.5% gelatin can be used for convenient storage and transportation of live DHV vaccines.

Recent Korean isolates of duck hepatitis virus reveal the presence of a new geno- and serotype when compared to duck hepatitis virus type 1 type strains.

Duck hepatitis was first reported in 1985 in Korea. The complete nucleotide sequence of two past Korean isolates, DHV-HS and DHV-HSS, isolated in 1994 and 1995, and four recent Korean isolates, AP-03337, AP-04009, AP-04114 and AP-04203 isolated in 2003 and 2004, were determined. Phylogenetic analysis using the 3D protein sequence confirmed that the previously characterized duck hepatitis virus type 1 strains and the six Korean isolates described here constitute a monophyletic group and form two clades/genotypes in which all except the four recent Korean isolates form one group (A) and the recent Korean isolates of 2003 and 2004 constitute a second group (B). Phylogenetic analysis of the VP1 protein supported the division into two different groups. Antisera raised against viruses of group A showed significant neutralizing cross-reaction against a member of the same genotype but not to a strain of group B and vice versa. These results demonstrated that the two genotypes also could be regarded as two different serotypes.

The hydrodynamic filter separator for removal of urban storm runoff.

The majority of storm runoff pollution is trapped in particles smaller than 100 microm in diameter. Solid particles smaller than 100 microm in diameter are not easily separated by conventional types of hydrodynamic separator, and remain in suspension in overflow. To overcome this problem, a HDFS (hydrodynamic filter separator) has been developed for treatment of the microparticles in urban storm runoff. We conducted a laboratory scale study on treatable potential of microparticles using HDFS that combined HDS with perlite filter. To determine the efficiency for various operation conditions, a series of experiments was performed with different solids concentrations and surface loading rate. The operation ranges of surface loading rates were 100 to 2,800 m3/m2/day, and influent solids concentrations were varied from 800 to 1,900 mg/L. Also, the particle size distribution was monitored to investigate the effects of surface loading rates on the particle size. Results indicated that the HDFS-inside type showed greater efficiency at solids separation than the other type.

Neural stem cells--a promising potential therapy for brain tumors.

Brain tumors can be highly aggressive and debilitating for many patients and lead to an untimely death in just a few months. Unfortunately, due to the location of many brain tumors, therapy with ionizing radiation, chemotherapeutic agents and/or surgery has limited rewards. In addition, the probability of totally removing highly infiltrative tumors, particularly gliomas, is extremely low and rarely provides a cure. The need for directed targeting and ablation of tumors with minimal damage to nearby healthy tissue has lead to the most recent findings and uses of neural stem cells for therapeutic treatment of brain tumors. Recently, some very promising studies have demonstrated that exogenous neural stem cells have the remarkable ability to migrate very long distances towards sites of metastasis after transplantation. These studies also show that intravascular injections of neural stem cells may lead to preferential migration towards central nervous system tumors. It has also been demonstrated that genetically modified neural stem cells, engineered to produce anti-tumor molecules, upon transplantation, have the ability to migrate towards tumors and reduce tumor mass directly or through a "bystander" effect. Here we review the current literature examining the promise of utilizing genetically modified neural stem cells as vehicles for CNS tumor therapy.

Highly pathogenic avian influenza in magpies (Pica pica sericea) in South Korea.

Highly pathogenic avian influenza (HPAI) is an extremely infectious, systemic viral disease of birds that produces high mortality and morbidity. HPAI was diagnosed in the three dead magpies (Pica pica sericea) submitted to the National Veterinary Research and Quarantine Service. At necropsy, the prominent lesions were multifocal or coalescing necrosis of the pancreas with enlargement of the livers and spleens. Microscopically, there were severely necrotizing pancreatitis and lymphocytic meningoencephalitis. Influenza viral antigen was also detected in areas closely associated with histologic lesions. Avian influenza virus was isolated from cecal tonsils and feces of the magpies. The isolated virus was identified as a highly pathogenic H5N1, with hemagglutinin proteolytic cleavage site deduced amino acid sequence of QREKRKKR/GLFGAIAG. To determine the pathogenicity of the isolate, eight 6-wk-old specific-pathogen-free chickens were inoculated intravenously with the virus, and all birds died within 24 hr after inoculation. This is the first report of HPAI in magpies.

The anesthetic management of a patient with hemoglobin M(Iwate).

IMPLICATIONS: Pulse oximetry is now considered essential for anesthetic management. We treated a patient with hemoglobin M(Iwate), a rare inheritable hemoglobinopathy rendering pulse oximetry completely useless because of its anomalous absorption spectrum.

A report of 14,195 applications of anesthetics to oral and maxillofacial surgery at one teaching dental hospital (1971-2000) centering around airway problems.

STUDY OBJECTIVES: To examine the validity of our methods of anesthesia, i.e., awake intubation and assisted manual ventilation, in coping with the anesthetic problems particular to oral and maxillofacial surgery (OMF surgery). DESIGN: Prospective study. SETTING: Operating room and ward of a dental teaching hospital. PATIENTS: 14,195 patients undergoing OMF surgery during the period from January 1971 to March 2000. MEASUREMENTS AND MAIN RESULTS: The kinds of anesthetic difficulties centering around airway problems and their frequency in OMF surgery were determined. In 2,401 patients (16.9%), awake intubation was employed because of definite or possible airway problems. No untoward effects due to awake intubation were noted. Volatile anesthetics were used with nitrous oxide (N2O) in 13,959 patients (98.3%), and their spontaneous respiration were assisted manually for the purpose of early detection of airway troubles such as accidental extubation, dislocation, kinking, and/or damage to the endotracheal tubes. Few accidents or complications were noted in relation to airway issues, and neither cardiac arrest nor death was experienced in these 14,195 patients. CONCLUSIONS: Based on a sufficient number of anesthetic applications, awake intubation and assisted manual ventilation were proved to be useful in coping with the anesthetic difficulties particular to OMF surgery.

Charged beads enhance cutaneous wound healing in rhesus non-human primates.

Enhanced cutaneous wound healing by positively charged cross-linked diethylaminoethyl dextran beads (CLDD) was studied in a standardized incisional wound model in 20 adult and 20 geriatric Macaca mulatta (rhesus) partitioned equally over five time periods. Physiologic saline served as a control. Soft-tissue linear incisions were prepared between and 1 cm inferior to the scapulae. There were four incisions per rhesus; each incision was 1.5 cm long with 1 cm of undisturbed tissue between incisions, and both the experimental CLDD and physiologic saline treatments were administered to each rhesus. The incision treatments were either CLDD and soft-tissue closure with 4-0 BioSyn sutures or sterile physiologic saline and closure with 4-0 BioSyn sutures. The hypothesis was CLDD would enhance cutaneous wound repair. Verification of the hypothesis consisted of clinical examinations and histologic and tensiometric evaluations on biopsy specimens at 10 and 15 days, whereas 5-day and 2- and 4-month groups were assessed clinically and biopsy specimens were assessed histologically. The clinical course of healing for all groups was unremarkable. At 10 days, incisions in adult rhesus treated with CLDD had a 30-percent greater tensile strength compared with the physiologic saline-treated incisions (p = 0.01), whereas for geriatric rhesus, the CLDD treatment proved to be 15 percent greater in tensile strength compared with the physiologic saline cohort (p = 0.11). By day 15, incisions in adult rhesus were 26 percent stronger than the saline treatment group (p = 0.07), and the difference was 36 percent (p = 0.02) for the geriatric rhesus. From 5 through 15 days, histologic observations revealed a gradual decrease in quantity and integrity of CLDD, with no remnants of CLDD at either 2 or 4 months. Macrophages and multinucleated giant cells were localized in the dermis and were associated with the CLDD. These cells decreased commensurately with the decrease of CLDD beads. The data suggest that CLDD can enhance significantly the tensile properties of healing cutaneous wounds in both adult and geriatric rhesus. Moreover, if the wound healing is enhanced in geriatric patients, this finding may be clinically germane to conditions where wound healing is compromised, such as in diabetics and patients on steroids.

Recombinant human bone morphogenetic protein-2 and collagen for bone regeneration.

The study reported describes a combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) and collagen (C) to regenerate bone. Unilateral critical-sized defects (CSDs) were prepared in radii of 32 skeletally mature New Zealand white rabbits. Rabbits were divided evenly among four treatments: autograft, absorbable C (Helistat), 35 microg of rhBMP-2 combined with absorbable C (rhBMP-2/C), and untreated CSDs. The two euthanasia periods were 4 and 8 weeks. Radiographs were taken the day of surgery, every 2 weeks, and at term and the percent of radiopacity was measured. Data analysis revealed a time-dependent increase in the percent radiopacity with rhBMP-2/C. Histological examination revealed the rhBMP-2/C treatment regenerated osseous contour by 8 weeks. According to quantitative histomorphometry, the CSD and C groups had significantly less new bone than either autograft or rhBMP-2/C (p < or = 0.05). The results suggest that rhBMP-2/C could be an effective therapy to restore segmental bone defects.

Radiomorphometry and biomechanical assessment of recombinant human bone morphogenetic protein 2 and polymer in rabbit radius ostectomy model.

The study objective was to determine the mechanical integrity and radiopacity of regenerated bone within critical-sized defects (CSDs) in radii of rabbits using recombinant human bone morphogenetic protein 2 (rhBMP-2) with a porous, biodegradable poly(D,L-lactic acid) (PDLLA) carrier (designated PLA). Twenty millimeter, unilateral radial ostectomies were created in 96 skeletally mature New Zealand white rabbits. The rabbits were randomly assigned to six treatment groups with two euthanasia periods. Treatment groups included unfilled defect (n = 8), segmental autograft (n = 8), PLA + 0 microg rhBMP-2 (n = 8), PLA + 17 microg rhBMP-2 (n = 8), PLA + 35 microg rhBMP-2 (n = 8), and PLA + 70 microg rhBMP-2 (n = 8). The radiopacity was significantly greater for the 35- and 70-microg rhBMP-2 groups at 4 weeks compared to unfilled controls, PLA only, and 17-microg rhBMP-2 groups and equivalent to the autograft. At 8 weeks all groups receiving rhBMP-2 were equivalent to the autograft and significantly greater than unfilled defects and PLA alone. Similarly, the biomechanical analysis indicated significantly greater torque at failure for the 35-microg rhBMP-2 group compared to all other groups at 4 weeks. By 8 weeks all groups receiving rhBMP-2 and autograft had significantly greater torque than unfilled controls and PLA alone. These radiomorphometric and biomechanical results indicate PLA may be a suitable carrier for rhBMP-2 used for skeletal regeneration.

[HR-CT evaluation of lung parenchymal alterations in patients following breast conservation therapy].

Twenty patients with early-stage breast cancer treated with breast conservation surgery and definite radiation, underwent computed tomography (added HR-CT) of the lungs before, immediately after, and at one, six, and twelve months after radiotherapy. During the follow-up period, 17 (85%) of the patients developed parenchymal alterations in the irradiated lung volume. We classified the parenchymal alterations into seven patterns: pattern 1 = septal line, 2 = nodular opacity, 3 = ground-glass opacity, 4 = consolidation, 5 = curvilinear opacity, 6 = aircyst accumulation, and 7 = irregularity of pleural surface. From one to six months after radiotherapy, 14 patients developed nodular opacities and ground glass opacities in the irradiated lung field. At 12 months after radiotherapy, fourteen patients were found to have aircyst accumulation and irregularity of the pleural surface. In this study, none of the patients presented any abnormal findings immediately after irradiation. There was no relationship between central lung distance or boost irradiation and the parenchymal alterations in the lung. On the other hand, there was a close relationship between oral anti-cancer agents and lung lesions. In conclusion, HR-CT was useful to evaluate morphologic changes in the irradiated lung.

Comparison of porous bone mineral and biologically active glass in critical-sized defects.

Several materials have been proposed as therapies to augment alveolar bone and to promote periodontal regeneration. However, there are an insufficient number of studies that effectively evaluated these therapies. Consequently, the purpose of this study was to compare bone regeneration promoted by porous bone mineral and biologically active glass. Unilateral critical-sized defects (CSDs) were prepared in the radii of 24 rabbits, divided evenly between 2 time periods (4 and 8 weeks) and between 2 treatment groups (porous bone mineral and biologically active glass). Evaluations consisted of clinical examinations, standardized radiography at baseline and every 2 weeks thereafter, as well as histology and histomorphometry. Data were analyzed by an unpaired Student t-test with significance established at P < or = 0.05. We determined that CSDs treated with porous bone mineral were significantly more radiopaque than biologically active glass-treated sites at both 4 and 8 weeks. Moreover, the amount of new bone was significantly greater at both 4 and 8 weeks in the porous bone mineral groups than in the biologically active glass groups. We concluded that in the rabbit radius CSD wound model, porous bone mineral appears to be more effective than biologically active glass in regenerating bone.

The effects of epinephrine and norepinephrine administered during local anesthesia on left ventricular diastolic function.

To evaluate the effects of epinephrine (E) and norepinephrine (NE) administered during local anesthesia on left ventricular diastolic function, we examined transmitral inflow patterns with pulsed Doppler echocardiography. Arterial blood pressure, heart rate, and transmitral inflow patterns were measured in 10 healthy volunteers when 3.6 mL of 2% lidocaine containing 1:80,000 E or 1:25,000 NE was injected supraperiosteally in the maxilla. The dosage of drug administered was 45 micrograms for E and 144 micrograms for NE. After the administration of E, heart rate was increased, but blood pressure was unchanged. Peak early velocity (R), peak atrial velocity (A), the ratio of A to R (A/R), and the deceleration rate (Dc) were increased, whereas the isovolumic relaxation time (IVRT) was shortened. The increase of R and Dc and the shortening of IVRT indicated an activation of left ventricular relaxation. After the administration of NE, blood pressure was increased and heart rate was decreased. A decrease in Dc, shortening of the acceleration half-time (AcT), and prolongation of IVRT were observed. These changes reflect impeded myocardial relaxation. We conclude that E activates left ventricular diastolic function and that NE, in contrast, impairs it.

[A case of acute monocytic leukemia cutis treated with total skin electron beam irradiation].

A 35-year-old man with acute monocytic leukemia (AMoL) cutis was treated with total skin electron beam irradiation (TSEBI), because the widespread skin infiltration of AMoL appeared after induction chemotherapy. A skin nodule was authenticated as leukemic cell by biopsy. The patient was irradiated 4 times a week with 200 cGy per fraction to a total dose of 1200 cGy, using 6 MeV electrons from 8 directions. The therapy was accomplished separately on the upper and lower halves of the body. Focus-skin distance was 310 cm. An acrylic plate applicator 1 cm in thickness was used. The dimensions were 90 x 90 cm inside length and 90 cm in height. After completion of radiotherapy, the nodular lesions of the skin nearly disappeared. Although the patient survived only 3.5 months after beginning of radiotherapy due to systemic relapse, recurrence of the skin nodule was not seen. In this case TSEBI was therefore a useful treatment for skin infiltration of AMoL.

Relationship between changes in power spectra of electroencephalograms and arterial halothane concentration in infants.

A power spectral analysis of electroencephalograms (EEGs) was performed in 30 infants who underwent plastic surgery for cleft lip or cleft palate. The study was conducted to investigate whether there was a significant correlation between EEG changes and arterial halothane concentration in infants. The power spectral analysis of EEGs was performed by the fast Fourier transform (FFT). Arterial halothane concentration was measured with gas chromatography. The relationship between the changes in the power spectra of EEGs and the arterial halothane concentration was examined by means of a multivariate analysis. Prior to administration of halothane, two kinds of EEG patterns were discernible. In one pattern the peak of the EEG power spectra was seen in the slow wave band (slow wave group); in the other the peak of the power spectra was present in the fast wave band (fast wave group). In the occipital lead the multiple correlation coefficient and the index of determination of the slow wave group were 0.71 and 0.50, respectively, and those of the fast wave group were 0.78 and 0.61, respectively. A significant correlation was proved to be present between the normalized values of the EEG power spectra and arterial halothane concentration in the occipital lead. Therefore, the results of the present study suggest that the relationship between changes in the power spectra of EEGs in the occipital lead and arterial halothane concentration in infants can be expressed by means of multiple regression formulas.