Identification of a novel RIG-I isoform and its truncating variant in Japanese eel, Anguilla japonica.

Retinoic acid-inducible gene-I (RIG-I) is a cytoplasmic viral RNA sensor that triggers the production of type I interferons (IFNs) and proinflammatory cytokines during viral infection. RIG-I gene has been identified previously in Japanese eel, Anguilla japonica. In the present study, we have characterized a novel isoform of RIG-I (designated as AjRIG-Ib) and its truncated variant (AjRIG-Ibv). The AjRIG-Ib encodes 940 amino acids (aa) consisting of two N-terminal caspase activation and recruitment domains (CARDs), a DEX(D/H) box RNA helicase domain, and a C-terminal regulatory domain (CTD). The AjRIG-Ibv encodes a protein of 843 aa, that shares similar structural organization with AjRIG-Ib, but lacking CTD. The gene expression analyses showed that AjRIG-Ib and AjRIG-Ibv were detectable in all tissues/organs examined, and AjRIG-Ib was the predominant form. The mRNA level of AjRIG-Ibv was upregulated rapidly at 8 h after the Poly I:C injection, and the significant increase of AjRIG-Ib was observed at 16 and 24 h post-injection (hpi). Laser confocal microscopy showed that AjRIG-Ib and AjRIG-Ibv were both located in cytoplasm. In addition, the overexpression of AjRIG-Ib or AjRIG-Ibv led to the increased activity of IFN promoter in transient transfection assay. Taken together, our results indicated that AjRIG-Ib and AjRIG-Ibv may play cooperative or somewhat complementary roles in coordinating the antiviral response in fish.

[Comparison of intensified myeloablative conditioning regime without antithymocytic globulin (ATG) with myeloablative conditioning regime for single-unit unrelated umbilical cord blood transplantation in hematological malignancies].

OBJECTIVE: To campare the effect and tolerance beween intensified myeloablative conditioning regime (IMCR) without antithymocyte globulin (ATG) and myeloablative conditioning regime (MCR) for single-unit unrelated umbilical cord blood transplantation (sUCBT) in hematological malignancies. METHODS: The clinical data of 190 patients with hematological malignancies undergoing sUCBT between April 2000 and December 2013 at Department of Hematology, Anhui Provincial Hospital were retrospectively analyzed, of whom 156 received IMCR without ATG (IMCR group), including 79 patient receiving total body irradiation (TBI)/cytosine arabinoside (Ara-C)/cyclophosphamide (CY) regime, 47 receiving fludarabine (Flu)/busulfan (Bu)/CY regime, and 30 receiving Ara-C/Bu/CY regime, and all of the 156 received a combination of cyclosporine A (CsA) and mycophelonate mofetil (MMF) for the prophylaxis of graft-versus-host disease (GVHD); the remaining 34 patients received MCR (MCR group), 30 patients receiving Bu/CY regime, and 4 receiving TBI/CY regime, all using CsA/MMF±ATG or methotrexate (MTX) for the prophylaxis of GVHD. The two groups were compared in disease status at the time of transplantation, characteristics of graft, transplantation effect, and transplantation-related complications. RESULTS: There were no statistically significant differences between the two groups in gender, disease type, human leukocyte antigen match, ABO blood type match, and disease status at the time of transplantation (all P>0.05). The median age and body weight at transplantation in the IMCR group were significantly higher than those in the MCR group (13 years vs 9 years, P=0.003; 44 kg vs 26 kg, P=0.000). The median doses of infused total nucleated cells (×10(7)/kg) and CD34(+) cells (×10(5)/kg) in the IMCR group were significantly lower than in the MCR group (3.87 vs 4.99, P=0.002; 2.00 vs 3.17, P=0.000). The cumulative incidence of myeloid engraftment on the 42th day and platelet engraftment on the 120th day in the IMCR group were remarkably higher than in the MCR group [96.33%(95%CI: 96.27%-96.39%)vs 82.30%(95%CI: 80.67%-83.93%), P=0.000; 86.44%(95%CI: 86.28%-86.60%)vs 51.17%(95%CI: 49.02%-53.32%), P=0.002]. There were no statistically significant differences in the incidences of grade Ⅱ to Ⅳ acute GVHD, grade Ⅲ to Ⅳ acute GVHD, and 2-year chronic GVHD(P=0.482, 0.928, 0.579). The incidence of pre-engraftment syndrome in the IMCR group was higher than in the MCR group(82.70% vs 47.06%, P=0.000). And 180-day transplantation-related mortality (TRM) in the IMCR group was lower than that in the MCR group [20.50%(95%CI: 20.28%-20.71%)vs 42.20% (95%CI: 41.32%-45.09%), P=0.004]. Up to October 2015, with a median follow-up of 44.2(22.7-188.9)months, the estimated 3-year overall survival and disease-free survival in the IMCR group were both significantly higher than those in the MCR group (62.90% vs 34.10%, P=0.000; 58.60% vs 34.10%, P=0.001). CONCLUSION: IMCR without ATG may improve the engraftment without increasing complications, reduce early transplantation-related mortality, and improve survival.

Emergence of Enterococcus species in the infectious microorganisms cultured from patients with endophthalmitis in South Korea.

PURPOSE: To investigate the microorganisms in culture-proven endophthalmitis and their susceptibilities to antimicrobial agents commonly used in South Korea. METHODS: Medical records of consecutive patients with culture-proven endophthalmitis at eight institutions between 1 January 2004 and 31 July 31 2010 were reviewed. Four categories of endophthalmitis were studied: postoperative, posttraumatic, endogenous, and unspecified. Outcome measures were culture-proven infectious organisms, antimicrobial susceptibilities, and final visual acuity in the patients. RESULTS: A total of 93 microorganisms were identified from 103 patients during the study period. The positive culture rate was 59.2 % (103/174). The most common organisms identified were Enterococcus faecalis (in 20.8 % of patients, 20/96), Staphylococcus epidermidis (18.8 %, 18/96), other coagulase-negative staphylococci (10.4 %, 10/96), Pseudomonas aeruginosa (6.3 %, 6/96), and Klebsiella pneumoniae (6.3 %, 6/96). Two cases of Enterococcus faecium (2.1 %) were recognized. Overall, 70 of 96 (73.0 %) isolates were Gram-positive bacteria, 22 (23.0 %) were Gram-negative bacteria, and 4 (4.2 %) were fungi. The most common organisms resulting in reduced light perception were E. faecalis and K. pneumoniae. CONCLUSIONS: The emergence of E. faecalis in endophthalmitis is mainly caused by the high incidence of E. faecalis in postoperative endophthalmitis. This increase also impacts the final visual acuity of the patients.

Relationships between pregnancy outcomes, biochemical markers and pre-pregnancy body mass index.

OBJECTIVE: We examined the relationships between pre-pregnancy maternal body mass index (BMI), pregnancy outcomes and biochemical markers. DESIGN: This study was conducted as a cross-sectional analysis. SUBJECTS: Korean women in their second and third trimesters of pregnancy were recruited at two hospitals in the metropolitan Seoul area. Pre-pregnancy BMI was categorized in four groups according to the Asia-Pacific standard. MEASUREMENTS: Fasting blood samples were obtained and analyzed for serum levels of homocysteine, folate and high-sensitivity C-reactive protein (hs-CRP). Concentrations of fetal fibronectin were assessed in the cervix and vagina, and cervical length was measured. RESULTS: Obese subjects had a lower education level and a lower income level than subjects of normal weight. The level of maternal stress was positively associated with pre-pregnancy BMI. Normal weight subjects were more likely to eat breakfast and consume meals of appropriate size than the rest of our sample. In overweight and obese subjects, weight gain during pregnancy was significantly lower than in the underweight and normal subjects. High pre-pregnancy maternal BMI increased the risks of preterm delivery (odds ratio (OR)=2.85, confidence interval (CI)=1.20-6.74), low-birth-weight (LBW) infants (overweight subjects: OR=5.07, CI=1.76-14.63; obese subjects: OR=4.49, CI=1.54-13.13) and macrosomia. In obese subjects, the average serum folate level was significantly lower than in the underweight subjects. In obese subjects, the average serum hs-CRP level was significantly higher than in the rest of our sample. CONCLUSION: Pregnancy outcomes are influenced by pre-pregnancy BMI. These findings suggest that women can minimize their risks of preterm delivery, LBW and macrosomia by maintaining normal pre-pregnancy BMI.

Molecular cloning and characterization of the STAT gene in Hyphantria cunea haemocytes.

A new insect member of the signal transducer and activator of transcription (STAT) family of transcription factors, Hyphantria cunea STAT (HcSTAT), was cloned from the lepidopteran H. cunea. The domain involved in DNA interaction and the Src homology 2 (SH2) domain were well conserved. During all developmental stages, the gene was expressed at a low level in the haemocytes, fat body cells, midgut, epidermis and Malpighian tubules. The haemocytes and Malpighian tubules showed transcriptional activation of HcSTAT upon Gram-negative and Gram-positive bacterial challenges. These challenges increased the induction and nuclear translocation of the HcSTAT protein that recognizes a STAT target site in H. cunea haemocytes. In vivo treatment with sodium orthovanadate translocated HcSTAT to the haemocyte nucleus. This study shows the involvement of the haemocyte Janus kinase/STAT pathway after microbial infection in lepidopteran insects.

Development of genetic markers in abalone through construction of a SNP database.

In the absence of a reference genome, single-nucleotide polymorphisms (SNP) discovery in a group of abalone species was undertaken by random sequence assembly. A web-based interface was constructed, and 11 932 DNA sequences from the genus Haliotis were assembled, with 1321 contigs built. Of these, 118 contigs that consisted of at least ten annotation groups were selected. The 1577 putative SNPs were identified from the 118 contigs, with SNPs in several HSP70 gene contigs confirmed by PCR amplification of an 809-bp DNA fragment. SNPs in the HSP70 gene were compared across eight abalone species. A total of 129 polymorphic sites, including heterozygote sites within and among species, were observed. Phylogenetic analysis of the partial HSP70 gene region showed separation of the tested abalone into two groups, one reflecting the southern hemisphere species and the other the northern hemisphere species. Interestingly, Haliotis iris from New Zealand showed a closer relationship to species distributed in the northern Pacific region. Although HSP genes are known to be highly conserved among taxa, the validation of polymorphic SNPs from HSP70 in this mollusc demonstrates the applicability of cross-species SNP markers in abalone and the first step towards universal nuclear markers in Haliotis.

Divergence between Asian, European and Canadian populations of the monogenean Pseudodactylogyrus bini indicated by ribosomal DNA patterns.

The monogenean Pseudodactylogyrus bini parasitizes the gills of eels belonging to the genus Anguilla. Circumstantial evidence suggests that the parasite has been spread accidentally from the Pacific area (East Asia) to Europe by the intercontinental eel trade. This is based on early descriptions of the parasites from Asian regions and the lack of records of the parasites in Europe before 1977. In addition, the susceptibility of European eels to infections with the parasite is significantly higher compared to that of Japanese eels, which could indicate that the European eel had not undergone co-evolution with this parasite. The present study was undertaken to elucidate the origin of the parasite by using molecular tools. Parasite samples were obtained from Europe (Germany), Asia (Taiwan) and Nova Scotia, the latter of which is the first record of P. bini in Canada. Sequencing of rDNA comprising part of the internal transcribed spacer 1 (ITS1) gene, 5.8S and part of ITS2 (1323 bp) showed that P. bini isolates from the first two regions showed high variability. One sequence was found both in a number of Asian parasites and with one to a few transitions in European parasites, which could indicate that they were split recently into the two regions. Other sequence variations suggested that one or a few genotypes of P. bini were imported on one occasion from Asia to Europe and that the two geographic isolates subsequently developed differently in the two regions. The Nova Scotian/Canadian isolates showed no variation and were found to be unique compared to the European and Taiwanese forms, indicating that this population is independent in origin. This could indicate that the Canadian parasites were introduced to North America on another occasion and independently of the European colonization.

[Meta-analysis of laparoscopic versus open surgery for palliative resection of the primary tumor in stage IV colorectal cancer].

Objective: To systematically evaluate the safety and efficacy of laparoscopic versus open surgery for palliative resection of the primary tumor in stage IV colorectal cancer. Methods: The databases of CNKI, Wanfang, VIP, PubMed, EMBASE and Cochrane Library were searched to retrieve randomized controlled trials (RCT) or clinical controlled trials (CCT) comparing laparoscopic surgery with open surgery for palliative resection of the primary tumor in stage IV colorectal cancer published from January 1991 to May 2019. Chinese search terms included "colorectum/colon/rectum" , "cancer/malignant tumor" , "laparoscopy" , "metastasis" , " IV" ; English search terms included "laparoscop*" , "colo*" , "rect*" , "cancer/tumor/carcinoma/neoplasm" , " IV" , "metasta*" . Inclusion criteria: (1) RCT or CCT, with or without allocation concealment or blinding; (2) patients with stage IV colorectal cancer that was diagnosed preoperatively and would receive resection of the primary tumor; (3) the primary tumor that was palliatively resected by laparoscopic or open procedure. Exclusion criteria: (1) no valid data available in the literature; (2) single study sample size ≤20; (3) subjects with colorectal benign disease; (4) metastatic resection or lymph node dissection was performed intraoperatively in an attempt to perform radical surgery; (5) duplicate publication of the literature. Two researchers independently evaluated the quality of the included studies. In case of disagreement, the evaluation was performed by discussion or a third researcher was invited to participate. The data were extracted from the included studies, and the Cochrane Collaboration RevMan 5.1.0 version software was used for this meta-analysis. Results: Four CCTs with a total of 864 patients were included in this study, including 216 patients in the laparoscopic group and 648 patients in the open group. Compared with the open group, except for longer operation time (WMD=37.60, 95% CI: 26.11 to 49.08, P<0.05), laparoscopic group had less intraoperative blood loss (WMD=-74.89, 95% CI: -144.78 to -5.00, P<0.05), earlier first flatus and food intake after surgery (WMD=-1.00, 95% CI: -1.12 to -0.87, P<0.05; WMD=-1.61, 95%CI: -2.16 to -1.06, P<0.05), shorter hospital stay (WMD=-2.01, 95% CI: -2.21 to -1.80, P<0.05) and lower morbidity of postoperative complication (OR=0.52, 95% CI: 0.35 to 0.77, P<0.05). However, no significant differences were found in time to start postoperative chemotherapy, postoperative chemotherapy rate, and mortality (P > all 0.05). Conclusion: Laparoscopic surgery for palliative resection of the primary tumor is safe and feasible to enhance recovery after surgery by promoting postoperative bowel function recovery, shortening hospital stay and reducing postoperative complication in stage IV colorectal cancer.

Comparative analysis of two attacin genes from Hyphantria cunea.

A full-length clone corresponding to attacin was isolated from a cDNA library made from fat body of immunized Hyphantria cunea larvae. This newly isolated attacin B shows characteristics different from those previously reported for attacin A. The two attacin cDNAs encode precursor proteins of 233 and 248 amino acid residues, respectively. The two attacins show 45.9% identity at the amino acid level, and 35.2% identity at the nucleotide level. Attacins A and B of H. cunea show significant identities with the attacins of Lepidoptera. Attacin B is a typical glycine-rich protein, while attacin A is leucine-rich. Attacin B is expressed from last instar larvae to adult, while attacin A showed stage-specific expression during the prepupal and pupal stages. Attacins A and B are predicted to have different secondary structure in that attacin A has no tendency to form helices but attacin B contains a substantial number of helices. Attacin A is induced at a trace level in infected larvae, while attacin B is strongly induced against Gram-positive and negative bacteria, fungi, and viruses. The attacin B transcripts were detected in fat body, epidermis and hemocytes after injection with Escherichia coli, Citrobacter freundii, or Candida albicans, but not in the midgut and Malpighian tubule. Recombinant attacin A showed no antibacterial activity, while recombinant attacin B showed strong antibacterial activity in proportion to the amount of the protein injected.

Cirrhotomimetic type hepatocellular carcinoma diagnosed after liver transplantation--eighteen months of follow-up: a case report.

Diffuse-type hepatocellular carcinoma (HCC) is a contraindication to liver transplantation (OLT). However, cirrhotomimetic HCC, which is a form of the diffuse type, is difficult to diagnose preoperatively, there are no published reports about its prognosis after OLT. We performed an OLT for a case of cirrhotomimetic HCC diagnosed postoperatively. This 41-years-old man was on the waiting list for OLT owing to hepatitis B virus-related liver cirrhosis and esophageal variceal bleeding. Three months before transplantation, newly developed small nodules were detected on computed tomography (CT); there were no interval changes on CT after 2 months. His serum value of alpha-fetoprotein (alpha-FP) was 327 ng/mL. The patient received a deceased donor liver transplantation and his postoperative course was uneventful. However, on pathologic findings, the explanted liver showed malignant cells in most cirrhotic nodules. So, the patient's pathologic diagnosis was cirrhotomimetic HCC. Triple immunosuppression was administered and steroid stopped at about 2 weeks after transplantation. Eighteen months after transplantation, alpha-FP was 1.5 ng/mL and there was no evidence of recurrence on follow-up CT. In conclusion, cirrhotomimetic HCC is rare and difficult to detect, preoperatively. Despite the short-term follow-up, we did not detect recurrence of HCC.

Benefit and pitfalls of newborn hearing screening.

The importance of universal newborn hearing screening (UNHS) in identifying hearing-impaired infants as early as possible is already well recognized. Transient evoked otoacoustic emissions (TEOAE) have been established as a reliable method for UNHS in full term infants. This is a cross sectional study between April 2003--December 2005. Thirteen thousand five hundred and ninety eight (13,598) newborns were screened for hearing loss with portable otoacoustic emission (OAE) before discharge. The initial coverage rate during the 3 years study period was 85.9% (13,598) with 89.2% (3762), 79.0% (4480) and 90.3% (5356) for 2003, 2004 and 2005 respectively. The mean age when hearing loss was diagnosed using ABR were 3.56 months old, 3.08 months old, and 2.25 months old and 3.01 months old for 2003, 2004, 2005 respectively and it was statistically significant. The defaulter rate at the third stage during the 3 years study period was 35% (21), 15.2% (7) and 18.2% (2) for 2003, 2004 and 2005 respectively. This study showed significant improvement in initial referral rate, coverage rate and age of diagnosis. However, we need to improve on high defaulter rates.

Fate of mandibular canals displaced by enlarged cystic lesions: does the inferior alveolar neurovascular bundle relocate to its original position?

Our aim was to identify the positional changes of the inferior alveolar neurovascular bundle and evaluate the relocation of the displaced mandibular canal after enucleation of a cyst. Seventy patients (72 sites) who had had cysts enucleated were divided into three groups based on the degree of encroachment of the cystic lesion into the mandibular canal and whether a bone graft had been inserted after the cyst had been enucleated. The mean (range) of patients' ages was 45 (18-75) years, and there were 29 male and 41 female patients. Group A comprised cysts with encroachment on the mandibular canal that were enucleated without a bone graft; Group B consisted of cysts with no encroachment of the mandibular canal, but were enucleated without a bone graft; and Group C comprised cysts with encroachment of the mandibular canal that were enucleated with a bone graft. The displacement of the mandibular canal was identified from analysis of computed tomographic (CT) images. Changes in the position of the mandibular canal were measured on panoramic radiographs. The mandibular canal was repositioned superiorly by a mean (SD) of 2.4 (1.65)mm after enucleation of the cyst, which was significant in Group A (p<0.001), but not in Groups B and C. These results indicate that the displaced inferior alveolar neurovascular bundles that were not surrounded by bony canal tended to relocate towards a supposedly normal position, and after enucleation of the cyst the mandibular canal was remodelled in this new location. This tendency to relocate was blocked by bone grafting. Bone grafts are therefore recommended in cases where enough bony height is required for future insertion of implants.

Administration of Cripto in GRP78 overexpressed human MSCs enhances stem cell viability and angiogenesis during human MSC transplantation therapy.

OBJECTIVES: The purpose of this study was to explore the effectiveness of concurrent GRP78 overexpression combined with Cripto on hMSC proliferation and migration both in vitro and in vivo. Specifically, we explored whether the treatment enhances effectiveness of hMSC transplantation in ischaemic tissue. MATERIALS AND METHODS: Human MSCs obtained from human adipose tissue were cultured in α-minimum essential medium (Hyclone, Logan, UT, USA) supplemented with 10% (v/v) foetal bovine serum (Hyclone), 100 U mL-1 penicillin and 100 µg mL-1 streptomycin. Murine hindlimb ischaemic model was generated with 8-week-old male nude BALB/c mice (Biogenomics, Seoul, Korea) maintained under a 12-h light/dark cycle following the established protocol with minor modification. Cellular injection was performed no later than 3 hour after surgery. Lipofectamine transfection, single-cell cultivation assay, transwell assay, scratch wound-healing migration assay, immunohistochemistry and western blotting assays were performed. RESULTS: Overexpression of GRP78 along with Cripto enhanced hMSC proliferation, migration and invasion. It increased interaction of surface GRP78 receptor with Cripto via JAK2/STAT3 pathway. We confirmed our proposed mechanism by showing that treatment with GRP78 antibody blocks the enhancement in vitro. In vivo, we observed that Cripto induced by the hypoxic environment in hindlimb ischaemic model interacts with the overexpressed GRP78 and increases hMSC proliferation, migration and invasion potentials as well as angiogenesis around transplanted ischaemic site via cytokine secretions. CONCLUSIONS: These results demonstrate supporting evidences that GRP78-Cripto combination technique offers novel strategy to enhance MSC proliferation, migration and invasion potentials as well as angiogenesis around ischaemic site, ultimately facilitating MSC-based transplantation therapy in ischaemic conditions.

Peroxisomes in Saccharomyces cerevisiae: immunofluorescence analysis and import of catalase A into isolated peroxisomes.

To isolate peroxisomes from Saccharomyces cerevisiae of a quality sufficient for in vitro import studies, we optimized the conditions for cell growth and for cell fractionation. Stability of the isolated peroxisomes was monitored by catalase latency and sedimentability of marker enzymes. It was improved by (i) using cells that were shifted to oleic acid medium after growth to stationary phase in glucose precultures, (ii) shifting the pH from 7.2 to 6.0 during cell fractionation, and (iii) carrying out equilibrium density centrifugation with Nycodenz containing 0.25 M sucrose throughout the gradient. A concentrated peroxisomal fraction was used for in vitro import of catalase A. After 2 h of incubation, 62% of the catalase was associated with, and 16% was imported into, the organelle in a protease-resistant fashion. We introduced immunofluorescence microscopy for S. cerevisiae peroxisomes, using antibodies against thiolase, which allowed us to identify even the extremely small organelles in glucose-grown cells. Peroxisomes from media containing oleic acid were larger in size, were greater in number, and had a more intense fluorescence signal. The peroxisomes were located, sometimes in clusters, in the cell periphery, often immediately adjacent to the plasma membrane. Systematic immunofluorescence observations of glucose-grown S. cerevisiae demonstrated that all such cells contained at least one and usually several very small peroxisomes despite the glucose repression. This finding fits a central prediction of our model of peroxisome biogenesis: peroxisomes form by division of preexisting peroxisomes; therefore, every cell must have at least one peroxisome if additional organelles are to be induced in that cell.

Feasibility of C2 monitoring in Korean renal transplantation.

BACKGROUND: In spite of efforts for simplified and optimal monitoring, variability of cyclosporine (CsA) absorption has shown limited clinical impact. We performed the present study to evaluate the feasibility of C2 monitoring and the optimal target C2 level in Korean recipients. PATIENTS AND METHODS: Sixty recipients who underwent first living donor kidney transplantations between December 2003 and May 2005 and who were treated with a regimen of CsA, mycophenolate mofetil, and steroid were enrolled in this study. CsA dose was adjusted according to conventional trough levels. Blood samples were collected just before (C0) and at 1, 2, 3, 4, 6, 8, and 12 hours (C1, C2, C3, C4, C6, C8 and C12) after dosing on days 2, 3, and 7 posttransplantation. On days 14 and 28, we determined C0, C1, C2, C3, and C4. We compared CsA levels between a no rejection versus a rejection group. RESULTS: In 8 recipients there were 1 or more acute rejection episodes (13.3%). C2 levels correlated closely with AUC0-4 on each day (r=.892-.944, P<.01), but C2 levels were not significantly different between the no rejection and the rejection group (P>.05). Mean C2 level on days 3 to 28 was significantly different between the 2 groups. (P=.045). One recipient (5.3%) with a mean C2 level greater than 1000 ng/mL underwent acute rejection. CONCLUSIONS: CsA concentration monitored as mean C2 levels early posttransplantation rather than a single point concentration on a single day was a predictor of acute rejection in kidney transplantation. Within the first month posttransplantation, the target C2 level is recommended to be over 1000 ng/mL for Korean recipients.

Role of HSPA1L as a cellular prion protein stabilizer in tumor progression via HIF-1α/GP78 axis.

The cellular prion protein (PrPC) is associated with metastasis, tumor progression and recurrence; however, the precise mechanisms underlying its action is not well understood. Our study found that PrPC degradation decreased tumor progression in colorectal cancer (CRC). In a CRC cell line and human CRC tissue exposed to hypoxia, induced heat-shock 70-kDa protein-1-like (HSPA1L) expression stabilized hypoxia-inducible factor-1α (HIF-1α) protein and promoted PrPC accumulation and tumorigenicity in vivo. PrPC was degraded via the proteasome pathway mediated by the ubiquitin-protein E3 ligase glycoprotein 78 (GP78), which interacts directly with PrPC. However, hypoxia-induced HSPA1L interacted with GP78 and inhibited its functions. HSPA1L knockdown facilitated the interaction of GP78 and PrPC, thereby increasing PrPC ubiquitination. Thus, GP78 was identified as the ubiquitinase for PrPC, thereby revealing an essential mechanism that controls PrPC levels in CRC. Our results suggest that the HSPA1L/HIF-1α/GP78 axis has a crucial role in PrPC accumulation during tumor progression.

Biochemical characterization of a novel hypoxanthine/xanthine dNTP pyrophosphatase from Methanococcus jannaschii.

A novel dNTP pyrophosphatase, Mj0226 from Methanococcus jannaschii, which catalyzes the hydrolysis of nucleoside triphosphates to the monophosphate and PPi, has been characterized. Mj0226 protein catalyzes hydrolysis of two major substrates, dITP and XTP, suggesting that the 6-keto group of hypoxanthine and xanthine is critical for interaction with the protein. Under optimal reaction conditions the k(ca)(t) /K(m) value for these substrates was approximately 10 000 times that with dATP. Neither endonuclease nor 3'-exonuclease activities were detected in this protein. Interestingly, dITP was efficiently inserted opposite a dC residue in a DNA template and four dNTPs were also incorporated opposite a hypoxanthine residue in template DNA by DNA polymerase I. Two protein homologs of Mj0226 from Escherichia coli and Archaeoglobus fulgidus were also cloned and purified. These have catalytic activities similar to Mj0226 protein under optimal conditions. The implications of these results have significance in understanding how homologous proteins, including Mj0226, act biologically in many organisms. It seems likely that Mj0226 and its homologs have a major role in preventing mutations caused by incorporation of dITP and XTP formed spontaneously in the nucleotide pool into DNA. This report is the first identification and functional characterization of an enzyme hydrolyzing non-canonical nucleotides, dITP and XTP.

Prognosis after liver transplantation predicted by preoperative MELD score.

The model for end-stage liver disease (MELD) has been an excellent predictor of 3-month mortality among cirrhotic patients awaiting orthotopic liver transplantation (OLT). The aim of this study was to evaluate whether the preoperative MELD score predicts short-term prognosis after OLT. We enrolled 98 adult liver transplant patients performed at our center from January 2001 to December 2002. In univariate analysis of risk factors for death within 3 and 6 months after liver transplantation, serum total bilirubin, creatinine, MELD score, hyponatremia with ascites, Child-Turcotte-Pugh (CTP) score were statistically significant parameters (P < .05). By logistic regression, none of the risk factors were subjected to multivariate analysis showed statistical significance. The odds ratios of the MELD score, hyponatremia with ascites, CTP score within 3 months were 0.997, 1.151, and 0.726 with 95% confidence intervals of [0.899, 1.105], [0.102, 12.959], and [0.389, 1.352], respectively. The odds ratio of MELD score, hyponatremia with ascites, CTP score within 6 months were 0.996, 0.914, and 0.764, with 95% confidence intervals of [0.901, 1.102], [0.089, 9.369], and [0.417, 1.401], respectively. Although MELD score has been a good predictor of short-term prognosis before OLT, MELD did not show an influence on the short-term prognosis after liver transplantation in this study.