Identification of Bacillus anthracis by rpoB sequence analysis and multiplex PCR

Comparative sequence analysis was performed upon Bacillus anthracis and its closest relatives, B. cereus and B. thuringiensis. Portions of rpoB DNA from 10 strains of B. anthracis, 16 of B. cereus, 10 of B. thuringiensis, 1 of B. mycoides, and 1 of B. megaterium were amplified and sequenced. The determined rpoB sequences (318 bp) of the 10 B. anthracis strains, including five Korean isolates, were identical to those of Ames, Florida, Kruger B, and Western NA strains. Strains of the "B. cereus group" were separated into two subgroups, in which the B. anthracis strains formed a separate clade in the phylogenetic tree. However, B. cereus and B. thuringiensis could not be differentiated. Sequence analysis confirmed the five Korean isolates as B. anthracis. Based on the rpoB sequences determined in the present study, multiplex PCR generating either B. anthracis-specific amplicons (359 and 208 bp) or cap DNA (291 bp) in a virulence plasmid could be used for the rapid differential detection and identification of virulent B. anthracis.     

Successful liver transplantation following veno-arterial extracorporeal membrane oxygenation in a child with fulminant Wilson disease and severe pulmonary hemorrhage: A case report

Son SK, Oh SH, Kim KM, Lee YJ, Jhang WK, Park SJ, Shin HJ, Park J‐J, Kim TH, Kim DY, Hwang S, Park K‐M, Lee Y‐J, Lee S‐G. Successful liver transplantation following veno‐arterial extracorporeal membrane oxygenation in a child with fulminant Wilson disease and severe pulmonary hemorrhage: A case report.
Pediatr Transplantation 2011. © 2011 John Wiley & Sons A/S. Abstract: Massive pulmonary hemorrhage and other serious cardiopulmonary diseases in patients with fulminant hepatitis result not only in graft failure but also mortality after LT. ECMO is used to treat children with cardiorespiratory failure refractory to conventional intensive care. We describe a five‐yr‐old girl with genetically confirmed fulminant Wilson disease and severe pulmonary hemorrhage who underwent successful primary LT following veno‐arterial ECMO. To our knowledge, this is the first report of successful primary LT in a patient using veno‐arterial ECMO. The present case demonstrates that ECMO, as a bridging modality to LT, may be necessary to manage both massive pulmonary hemorrhage and possible graft loss because of hypoxemia.     

Clinical Evaluation of Compression Ratios using JPEG2000 on Computed Radiography Chest Images

The efficient compression of radiographic images is of importance for improved storage and network utilization in support of picture archiving and communication systems (PACS) applications. The DICOM Working Group 4 adopted JPEG2000 as an additional compression standard in Supplement 61 over the existing JPEG. The wavelet-based JPEG2000 can achieve higher compression ratios with less distortion than the Discrete Cosine Transform (DCT)-based JPEG algorithm. However, the degradation of JPEG2000-compressed computed radiography (CR) chest images has not been tested comprehensively clinically. The authors evaluated the diagnostic quality of JPEG2000-compressed CR chest images with compression ratios from 5:1 to 200:1. An ROC (receiver operating characteristic analysis) and t test were performed to ascertain clinical performance using the JPEG2000-compressed images. The authors found that compression ratios as high as 20:1 can be utilized without affecting lesion detectability. Significant differences between the original and the compressed CR images were not recognized up to compression ratio of 50:1 within a confidence level of 99%.     

Risk Factor and Clinical Outcome of Bronchiolitis Obliterans Syndrome after Allogeneic Hematopoietic Stem Cell Transplantation

PurposeThe development of bronchiolitis obliterans syndrome (BOS) after allogeneic hematopoietic stem cell transplantation (HSCT) deteriorates patients'' quality of life. This study aimed to analyze the prevalence, clinical features, risk factors and prognostic factors of BOS.ResultsOf 860 patients who survived for ≥100 days, 36 (4.2%) met the diagnostic criteria. The duration of BOS development after transplantation was 466.00 (284.00–642.75) [median (interquartile range)] days. The risk factor for the development of BOS was peripheral blood as the stem cell source with a hazard ratio (HR) of 2.550 [95% confidence interval (CI): 1.274–5.104, p=0.008]. In multivariate analysis, pretransplant FEV₁/FVC (HR: 0.956, 95% CI: 0.921–0.993, p=0.020) and time from HSCT to diagnosis of BOS (HR: 0.997, 95% CI: 0.994–0.999, p=0.009) were independent prognostic factors associated with mortality.ConclusionPeripheral blood as a stem cell source is a risk factor for the development of BOS. A decreased pretransplant FEV₁/FVC and shorter duration of time from transplantation to diagnosis of BOS are poor prognostic factors for BOS.     

Prognostic factors of the long-term survival after transjugular intrahepatic portosystemic shunt in the treatment of gastric and esophageal variceal bleeding

Transjugular intrahepatic portosystemic shunt (TIPSS) is a promising method of treatment for gastric or esophageal variceal bleeding. This study was performed to determine the prognostic factors contributing to the survival of patients after TIPSS for gastric or esophageal variceal bleeding. One hundred and fifty-five patients who underwent TIPSS between September 1991 and March 2001 were followed up by clinical examination, upper gastrointestinal endoscopy, and Duplex sonography. The mean portohepatic pressure gradient prior to TIPSS was 20.5+/-9.93 mmHg and dropped to 10.7+/-6.62 mmHg after TIPSS (p<0.001). The cumulative survival rate was 75.1% at 6 months, 66.6% at 1 yr, 58.4% at 2 yr, and 38.1% at 5 yr. Survival after TIPSS was inversely related to the Child-Pugh classification (p<0.05). The rebleeding rate was 18.3% at 6 months, 21.0% at 1 yr, 32.8% at 2 yr, and 53.1% at 5 yr. The causes of deaths were hepatic failure (53.5%), recurrent variceal bleeding (11.6%), pneumonia (4.6%), sepsis (3.5%), hepatic encephalopathy (2.3%), and unknown (17.4%). Multivariate analysis (Cox proportional hazard model) revealed that the Child-Pugh classification and age were statistically significant independent prognostic factors. In conclusion, TIPSS is an effective method of treatment for variceal bleeding in cases where other treatment modalities including endoscopic therapy are unsuccessful and the most important prognostic factors are preprocedural hepatic reserve (Child-Pugh class) and age.     

Application of RNA polymerase beta-subunit gene (rpoB) sequences for the molecular differentiation of Legionella species

The nucleotide sequences of the partial rpoB gene were determined from 38 Legionella species, including 15 serogroups of Legionella pneumophila. These sequences were then used to infer the phylogenetic relationships among the Legionella species in order to establish a molecular differentiation method appropriate for them. The sequences (300 bp) and the phylogenetic tree of rpoB were compared to those from analyses using 16S rRNA gene and mip sequences. The trees inferred from these three gene sequences revealed significant differences. This sequence incongruence between the rpoB tree and the other trees might have originated from the high frequency of synonymous base substitutions and/or from horizontal gene transfer among the Legionella species. The nucleotide variation of rpoB enabled more evident differentiation among the Legionella species than was achievable by the 16S rRNA gene and even by mip in some cases. Two subspecies of L. pneumophila (L. pneumophila subsp. pneumophila and subsp. fraseri) were clearly distinguished by rpoB but not by 16S rRNA gene and mip analysis. One hundred and five strains isolated from patient tissues and environments in Korea and Japan could be identified by comparison of rpoB sequence similarity and phylogenetic trees. These results suggest that the partial sequences of rpoB determined in this study might be applicable to the molecular differentiation of Legionella species.     

Comparison of full length sequences of hepatitis B virus isolates in hepatocellular carcinoma patients and asymptomatic carriers of Korea

Relatively few genomic sequences of Korean hepatitis B virus (HBV) isolates are available. Moreover, no comparative study has been made between the full-length genomes of Korean HBV isolates and clinical status. To evaluate mutations in HBV isolates obtained from chronically infected HBV patients in terms of clinical significance, we determined the genomic sequences of HBV isolates obtained from three hepatocellular carcinoma (HCC) patients (He52, He53, and He82) and from three asymptomatic carriers (He74, He100, and He127). A comparison of sequence variations showed that the HBV isolates from the three HCC patients showed higher frequencies of mutation than the isolates from the three asymptomatic carriers. Three characteristic mutation patterns were identified in the HBV isolates from the HCC patients, which distinguished the HBV isolates from the asymptomatic carriers. First, HBV isolates from the three HCC patients both had double mutations in a core promoter (T1762/A1764) and a precore mutation (A1896). Second, although these isolates belonged to genotype C, 11 amino acids deletions in the preS1 region, specific for HBV genotype D, were detected in the isolates of two HCC patients (He52 and He82). Third, mutations (I127T/N, K130M, and V131I) at three codons in the carboxy functional region of X protein were observed in isolates from all three HCC patients. Additionally, phylogenetic analysis based on the entire HBV sequences showed that all six isolates belonged to genotype C2, as do other Korean strains.