Predisposing Factors for Posttraumatic Osteoarthritis After Malleolus Fracture Fixation in Patients Younger Than 50 Years.

BACKGROUND: The purpose of this study was to identify the risk factors for posttraumatic osteoarthritis (OA) after surgery for ankle fractures in patients aged ≤50 years. METHODS: We performed a retrospective review of consecutive patients who underwent surgery for ankle fractures and were followed up for a minimum period of 5 years. The patients were assigned to 2 groups according to the presence of advanced OA at the last follow-up. Binary logistic regression was used to model the correlation between risk factors and OA. Functional outcomes were assessed using the Foot and Ankle Outcome Score. RESULTS: The data of 332 patients who met the inclusion criteria were included in the analysis. The overall rate of posttraumatic arthritis was 27.7% (nonarthritis group: 240 patients, arthritis group: 92 patients). The arthritic change was significantly affected by BMI (95% confidence interval [CI] 1.29-19.76; adjusted odds ratio [OR] ≥ 30, 6.56), fracture-dislocation injury (CI 1.66-11.57; adjusted OR, 4.06), posterior malleolus (PM) fracture (CI 1.92-12.73, adjusted OR > 25% of the articular surface, 5.72), and postoperative articular incongruence (CI 1.52-18.10; adjusted OR, 7.21). The mean scores of the arthritis group were lower than those in the nonarthritis group (P < .05). CONCLUSION: Obesity, fracture-dislocation injury, concomitant large PM fracture, and articular incongruence were risk factors of posttraumatic OA after surgery for ankle fractures. Surgeons should be aware that accurate reduction is critical in patients with ankle fractures with associated large PM fractures, especially those with obesity or severe initial injuries such as fracture-dislocation. LEVEL OF EVIDENCE: Level III, case control study.

Efficacy of 2-stage revision using a prosthesis of antibiotic-loaded acrylic cement spacer with or without cortical strut allograft in infected total elbow arthroplasty.

PURPOSE: We aimed to evaluate the efficacy of a self-manufactured prosthesis of antibiotic-loaded acrylic cement (PROSTALAC) spacer with or without cortical strut allograft in infected total elbow arthroplasty. METHODS: Between March 2009 and February 2018, we enrolled 18 patients (mean age, 66.9 years) who underwent 2-stage revision arthroplasty for prosthetic infection following total elbow arthroplasty. After implant removal in the first stage, we performed débridement and PROSTALAC insertion. During the second stage, we performed reimplantation using a cortical strut allograft for patients with a considerably severe bone defect. The mean follow-up period was 34 months (range, 25-60 months), during which we evaluated the Mayo Elbow Performance Score (MEPS), range of motion (ROM), and blood markers. RESULTS: In all 18 patients, infection control was ensured using intravenous (IV) antibiotic therapy for 6 weeks or IV antibiotics for 4 weeks converting to oral antibiotics for 2 weeks following PROSTALAC insertion. The mean visual analog scale score improved from 8 points preoperatively to 2 points postoperatively, and the mean MEPS improved from 32 points preoperatively to 82 points postoperatively (P < .05). The average ROMs at the last follow-up were 9° to 132° from extension to flexion, respectively. Two patients experienced ulnar nerve neuropraxia after surgery, from which they were resolved. Moreover, 2 and 4 patients developed superficial wound infection and triceps insufficiency, respectively, and there was no infection recurrence. CONCLUSION: In the management of elbow prosthetic infection, 2-stage revision arthroplasty using PROSTALAC spacer insertion in the first stage and cortical strut allograft in the second stage for patients with severe bone defect revealed good clinical results and relatively low infection recurrence rates. However, the complication rate is substantial.

Comprehensive identification of LMW-GS genes and their protein products in a common wheat variety.

Although it is well known that low-molecular-weight glutenin subunits (LMW-GS) from wheat affect bread and noodle processing quality, the function of specific LMW-GS proteins remains unclear. It is important to find the genes that correspond to individual LMW-GS proteins in order to understand the functions of specific proteins. The objective of this study was to link LMW-GS genes and haplotypes characterized using well known Glu-A3, Glu-B3, and Glu-D3 gene-specific primers to their protein products in a single wheat variety. A total of 36 LMW-GS genes and pseudogenes were amplified from the Korean cultivar Keumkang. These include 11 Glu-3 gene haplotypes, two from the Glu-A3 locus, two from the Glu-B3 locus, and seven from the Glu-D3 locus. To establish relationships between gene haplotypes and their protein products, a glutenin protein fraction was separated by two-dimensional gel electrophoresis (2-DGE) and 17 protein spots were analyzed by N-terminal amino acid sequencing and tandem mass spectrometry (MS/MS). LMW-GS proteins were identified that corresponded to all Glu-3 gene haplotypes except the pseudogenes. This is the first report of the comprehensive characterization of LMW-GS genes and their corresponding proteins in a single wheat cultivar. Our approach will be useful to understand the contributions of individual LMW-GS to the end-use quality of flour.

Functional analysis of the aroC gene encoding chorismate synthase from Xanthomonas oryzae pathovar oryzae.

Xanthomonas oryzae pv. oryzae causes bacterial blight in rice, and this bacterial blight has been widely found in the major rice-growing areas. We constructed a transposon mutagenesis library of X. oryzae pv. oryzae and identified a mutant strain (KXOM9) that is deficient for pigment production and virulence. Furthermore, the KXOM9 mutant was unable to grow in minimal medium lacking aromatic amino acids. Thermal asymmetric interlaced-PCR and sequence analysis of KXOM9 revealed that the transposon was inserted into the aroC gene, which encodes a chorismate synthase in various bacterial pathogens. In planta growth assays revealed that bacterial growth of the KXOM9 mutant in rice leaves was severely reduced. Genetic complementation of this mutant with a 7.9-kb fragment containing aroC restored virulence, pigmentation, and prototrophy. These results suggest that the aroC gene plays a crucial role in the growth, attenuation of virulence, and pigment production of X. oryzae pv. oryzae.

Treatment and clinical outcome of needle-track seeding from hepatocellular carcinoma.

BACKGROUND/AIMS: Needle-track seeding is a rare but important complication of diagnostic and therapeutic ultrasound (US)-guided procedures in hepatocellular carcinoma (HCC). We examined the frequency of needle-track seeding after US-guided percutaneous ethanol injection (PEI), fine-needle aspiration biopsy (FNAB), and percutaneous transhepatic biliary drainage (PTBD) in order to determine the appropriate treatment for needle-track seeding and its clinical outcome. METHODS: We analyzed the clinical characteristics and treatment outcomes in eight patients who experienced needle-track seeding from HCC after an US-guided procedure (FNAB, PEI, or PTBD) between January 1990 and July 2004. RESULTS: Seven (0.14%) of 5,092 patients who experienced needle-track seeding (2 after PEI, 4 after FNAB, and 1 after PTBD) during the study period and 1 other patient who experienced needle-track seeding recently were recruited for this study. Two of the eight patients underwent mass excision and the other six patients underwent en-bloc wide excision for the needle-track seeding. Tumors recurred in the needle-tracks in both patients who underwent mass excision but not in the six patients who underwent en-bloc wide excision. Mortality occurred in three patients who experienced the recurrence and progression of intrahepatic HCC. CONCLUSIONS: The incidence of needle-track seeding after US-guided procedures in HCC was 0.14%. En-bloc wide excision seems to be the optimal treatment for minimizing the probability of tumor recurrence due to needle-track seeding.

Isolation and characterization of NgRLK1, a receptor-like kinase of Nicotiana glutinosa that interacts with the elicitin of Phytophthora capsici.

Elicitins, extracellular proteins from Phytophthora fungi, elicit a hypersensitivity response (HR), including systemic acquired resistance, in some plants. The elicitin capsicein (approximately 10 kDa) was purified by FPLC from culture filtrates of P. capsici. Purified native and recombinant capsicein induced a hypersensitive response in leaves of the non-host plants Nicotiana glutinosa and Brassica rapa subsp. pekinensis. To search for candidate capsicein-interacting proteins from N. glutinosa, a yeast two-hybrid assay was used. We identified a protein interactor that is homologous to a serine/threonine kinase of the plant receptor-like kinase (RLK) group and designated it NgRLK1. The ORF of NgRLK1 encodes a polypeptide of 832 amino acids (93,490 Da). A conserved domain analysis revealed that NgRLK1 has structural features typical of a plant RLK. NgRLK1 was autophosphorylated, with higher activity in the presence of Mn2+ than Mg2+.

Molecular analysis of the hrp gene cluster in Xanthomonas oryzae pathovar oryzae KACC10859.

Xanthomonas oryzae pathovar oryzae is the causal agent of rice bacterial blight. The plant pathogenic bacterium X. oryzae pv. oryzae expresses a type III secretion system that is necessary for both the pathogenicity in susceptible hosts and the induction of the hypersensitive response in resistant plants. This specialized protein transport system is encoded by a 32.18kb hrp (hypersensitive response and pathogenicity) gene cluster. The hrp gene cluster is composed of nine hrp, nine hrc (hrp conserved) and eight hpa (hrp-associated) genes and is controlled by HrpG and HrpX, which are known as regulators of the hrp gene cluster. Before mutational analysis of these hrp genes, the transcriptional linkages of the core region of the hrp gene cluster from hpaB to hrcC of the X. oryzae pv. oryzae KACC10859 was determined and the non-polarity of EZTn5 insertional mutagenesis was demonstrated by reverse transcription polymerase chain reaction. Pathogenicity assays of these non-polar hrp mutants were carried out on the susceptible rice cultivar, Milyang-23. According to the results of these assays, all hrp-hrc, except hrpF, and hpaB mutants lost their pathogenicity, which indicates that most hrp-hrc genes encode essential pathogenicity factors. On the other hand, most hpa mutants showed decreased virulence in a different pattern, i.e., hpa genes are not essential but are important for pathogenicity.

Predicting the interactome of Xanthomonas oryzae pathovar oryzae for target selection and DB service.

BACKGROUND: Protein-protein interactions (PPIs) play key roles in various cellular functions. In addition, some critical inter-species interactions such as host-pathogen interactions and pathogenicity occur through PPIs. Phytopathogenic bacteria infect hosts through attachment to host tissue, enzyme secretion, exopolysaccharides production, toxins release, iron acquisition, and effector proteins secretion. Many such mechanisms involve some kind of protein-protein interaction in hosts. Our first aim was to predict the whole protein interaction pairs (interactome) of Xanthomonas oryzae pathovar oryzae (Xoo) that is an important pathogenic bacterium that causes bacterial blight (BB) in rice. We developed a detection protocol to find possibly interacting proteins in its host using whole genome PPI prediction algorithms. The second aim was to build a DB server and a bioinformatic procedure for finding target proteins in Xoo for developing pesticides that block host-pathogen protein interactions within critical biochemical pathways. DESCRIPTION: A PPI network in Xoo proteome was predicted by bioinformatics algorithms: PSIMAP, PEIMAP, and iPfam. We present the resultant species specific interaction network and host-pathogen interaction, XooNET. It is a comprehensive predicted initial PPI data for Xoo. XooNET can be used by experimentalists to pick up protein targets for blocking pathological interactions. XooNET uses most of the major types of PPI algorithms. They are: 1) Protein Structural Interactome MAP (PSIMAP), a method using structural domain of SCOP, 2) Protein Experimental Interactome MAP (PEIMAP), a common method using public resources of experimental protein interaction information such as HPRD, BIND, DIP, MINT, IntAct, and BioGrid, and 3) Domain-domain interactions, a method using Pfam domains such as iPfam. Additionally, XooNET provides information on network properties of the Xoo interactome. CONCLUSION: XooNET is an open and free public database server for protein interaction information for Xoo. It contains 4,538 proteins and 26,932 possible interactions consisting of 18,503 (PSIMAP), 3,118 (PEIMAP), and 8,938 (iPfam) pairs. In addition, XooNET provides 3,407 possible interaction pairs between two sets of proteins; 141 Xoo proteins that are predicted as membrane proteins and rice proteomes. The resultant interacting partners of a query protein can be easily retrieved by users as well as the interaction networks in graphical web interfaces. XooNET is freely available from http://bioportal.kobic.kr/XooNET/.

Analysis of virulence and growth of a purine auxotrophic mutant of Xanthomonas oryzae pathovar oryzae.

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight of rice. A random insertional mutant library of Xoo KACC10331 was constructed using a Tn5-derived transposon, and the virulence of the mutants against the susceptible rice cultivar IR24 was assayed. After the virulence assay, the M793 (purD::Tn5) mutant that had reduced virulence against the rice plants was isolated. Thermal asymmetric interlaced-PCR and sequence analysis revealed that the transposon was inserted into the purD gene (encodes a phosphoribosylamine-glycine ligase) of the M793 mutant. The reverse transcriptase-PCR assay revealed that the mutation of the purD gene did not affect the expression of other purine biosynthesis genes. However, the M793 mutant required exogenous purines and thiamine for growth in minimal media. These results indicate that the purD gene plays a crucial role in the growth and virulence of Xoo.

Ribosome-inactivating activity and cDNA cloning of antiviral protein isoforms of Chenopodium album.

We have characterized a novel type I ribosome-inactivating protein (CAP30) from the leaves of Chenopodium album. Purified native CAP30 depurinated the ribosomes of Chenopodium, tomato, and tobacco leaves in vitro. To further characterize this protein, cDNA clones were isolated from a leaf cDNA library using a DNA probe derived from the N-terminal amino acid sequence. Two full-length cDNA clones, CAP30A and CAP30B, were isolated. The two clones were highly homologous (91.4% identity over 280 amino acids) at the deduced amino acid level. Both contain a putative signal peptide of 25 amino acid and a conserved domain commonly found in ribosome-inactivating proteins. This suggests that CAP30 is a single-chain ribosome-inactivating protein. Expression of CAP30 mRNA peaked twice, at 12 and 72 h, after tobacco mosaic virus (TMV) infection or wounding. Transformed Escherichia coli cells expressing pre- or mature CAP had greatly reduced growth rates. These results suggest that CAP30 functions as a broad-spectrum defense-related protein with both antiviral and anti-microbial activity.