Analysis of clinical characteristics of infections caused by shewanella species.

PURPOSE: The Shewanella genus is a rare pathogen of marine origin. In recent years, there has been a continuous increase in infection cases caused by this bacterium, and we have observed the uniqueness of infections caused by this microorganism. MATERIALS AND METHODS: This study conducted a retrospective analysis of the medical history and laboratory examination data of patients infected with the Shewanella genus over the past decade. Additionally, it employed bioinformatics methods to analyze the relevant virulence factors and antibiotic resistance genes associated with the Shewanella genus. RESULTS: Over the past 10 years, we have isolated 51 cases of Shewanella, with 68.82% being Shewanella putrefaciens (35/51 cases) and 31.37% being Shewanella algae (16/51 cases). Infected individuals often had underlying diseases, with 39.22% (20/51) having malignant tumors and 25.49% (13/51) having liver and biliary system diseases primarily characterized by stones. The majority of patients, 62.74% (32/51), exhibited mixed infections, including one case with a combination of infections from three other types of bacteria and five cases with a combination of infections from two other types of bacteria. The identified microorganisms were commonly resistant to ticarcillin-clavulanic acid (23.5%), followed by cefoperazone-sulbactam (19.6%), ciprofloxacin (17.6%), and cefotaxime (17.6%). Bioinformatics analysis indicates that Shewanella can express bile hydrolysis regulators and fatty acid metabolism regulators that aid in adapting to the unique environment of the biliary tract. Additionally, it expresses abundant catalase, superoxide dismutase, and two-component signal transduction system proteins, which may be related to environmental adaptation. Shewanella also expresses various antibiotic resistance genes, including beta-lactamases and aminoglycoside modification enzymes. Iron carriers may be one of its important virulence factors. CONCLUSIONS: We speculate that the Shewanella genus may exist as a specific colonizer in the human body, and under certain conditions, it may act as a pathogen, leading to biliary infections in the host.

Genus Shewanella: A Potential Intestinal Colonizer Associated With Post-Operative Surgical Site Infections in Coastal Regions.

Background: This study aims to elucidate the clinical characteristics of Shewanella-related surgical site infections (SSIs) and assess the risk of mortality in patients by establishing a predictive model. Patients and Methods: A retrospective analysis of medical history and laboratory data of Shewanella-related SSI patients over the past decade was conducted via the electronic medical record (EMR) system. A predictive model for mortality risk in Shewanella-related SSI patients was established using plasma interleukin-6 (IL-6) levels combined with the Howell-PIRO scoring system. Results: Over the past 10 years, 45 strains of Shewanella were isolated from specimens such as bile, drainage fluid, and whole blood in patients with digestive tract SSIs. Among them, 21 of 45 (46.67%) patients underwent malignant tumor resection of the digestive system, 14 of 45 (31.11%) underwent endoscopic retrograde cholangiopancreatography (ERCP) common bile duct exploration or the stone removal, and seven of 45 (15.56%) were trauma repair patients with fractures and abdominal injuries. Among the 45 Shewanella-related SSI patients, 10 died within 30 days of infection, six cases involved infections with more than two other types of bacteria. The combined use of IL-6 and Howell-PIRO scores for mortality risk assessment yielded an receiver operating characteristic (ROC) curve with an area under the curve (AUC) of 0.9350, a positive predictive value of 92.71%, a negative predictive value of 94.58%, a diagnostic sensitivity of 95.35%, and a diagnostic specificity of 92.14%-all higher than the model using IL-6 or Howell-PIRO scores alone. Conclusions: We found that residents in coastal areas faced an increased risk of Shewanella-related SSI. Moreover, the higher the number of concurrent microbial infections occurring alongside Shewanella-related SSI, the greater the mortality rate among patients. The combined application of plasma IL-6 levels and the Howell-PIRO scoring system is beneficial for assessing patient mortality risk and guiding timely and proactive clinical interventions.

[Effects of microbial agents on bacterial community composition during swine manure composting]. / å¾®ç”Ÿç‰©èŒå‰‚å¯¹çŒªç²ªå †è‚¥ä¸­ç»†èŒç¾¤è½ç»“æž„çš„å½±å“.

The process of swine manure and wheat straw aerobic composting was examined, with exogenous microbial agents being added in treatment group. The physicochemical properties were measured by conventional methods, and bacterial community characteristics were investigated by high throughput sequencing analysis. Exogenous microbial agents increased high-temperature duration, reduced pH value at the end of fermentation stage, augmented total nitrogen content, reduced C/N ratio. Results from principal component analysis showed that microbial agents affected the stability of bacterial community during composting. At the phylum level, the relative abundance of Firmicutes, Proteobacteria, and Chloroflexi was higher in the treatment group. At the class level, the relative abundance of Clostridia, Alphaproteobacteria, and Gammaproteobacteria in the treatment group were higher at the mesophilic and thermophilic phases. At the family level, Peptostreptococcaceae, Clostridiaceae_1, and Halanaerobiaceae of the Clostridia and Micromonosporaceae in the treatment group were higher at the mesophilic and thermophilic phases. Halocella was significantly positively correlated with exogenous microbial agents, while Ammoniibacillus was significantly negatively correlated with it. It suggested that microbial agents significantly changed the physicochemical properties and bacterial community structure during swine composting.

A New Method Aimed to Quickly Identify Pathogen and Drug Susceptibility Test Based on Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry Combined with Flow Cytometry.

AIM: To discuss the significance and applied value in the rapid identification and drug susceptibility test for blood stream infection (BSI) using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) combined with flow cytometry (FCM). METHODS: The bacteria were separated from the positive blood culture bottle using the separation gel-adsorption method system, and then applying MALDI-TOF MS combined with FCM to identify pathogen and drug susceptibility test quickly. RESULTS: The efficiency of the separation gel-adsorption method for gram-negative bacterium, gram-positive bacteria, and fungi is 71%, 74%, and 88%, respectively. The results of identifying pathogens using MALDI-TOFMS are in agreement with results obtained using VITEK®2 (bioMérieux, Marcy l'Etoile, France); both methods can identify 90% of bacteria to species. For fungi, MALDI-TOF MS can identify 75% fungi to species, which is superior to VITEK2, which identifies 60% fungi to species. The results of drug susceptibility test using FCM are almost identical to VITEK2; additionally, the addition of fluorescein diacetate can identify the heterogenic drug-resistant strains. CONCLUSIONS: We can quickly identify pathogen and drug-susceptibility test based on MALDI-TOF MS combined with FCM, which is consistent with traditional methods and can shorten the report time from 36-72 hour to 3 hours. More importantly, these methods are of great significance and clinical importance for the rapid identification of BSI.

Antibacterial activity of N-methylbenzofuro[3,2-b]quinoline and N-methylbenzoindolo[3,2-b]-quinoline derivatives and study of their mode of action.

The emergence of multidrug-resistant bacteria causes an urgent need for new generation of antibiotics, which may have a different mechanism of inhibition or killing action from the existing. Targeting at the inhibition of bacterial cell division via the control of FtsZ function is one of the effective and promising approaches. Some natural extracts from plants such as sanguinarine and berberine (analogs of pyridinium compounds) are known to alter FtsZ function. In this study, a series of novel quaternary pyridinium compounds was constructed based on the N-methylbenzofuro[3,2-b]quinoline and N-methylbenzoindolo[3,2-b]-quinoline derivatives and their antibacterial activity against nine significant pathogens was investigated using broth microdilution method. In the in vitro assay, the compounds showed strong antibacterial activities against various testing strains, which include some drug-resistant strains such as methicillin-resistant S. aureus and vancomycin-resistant E. faecium. Our results of morphology change of B. subtilis cells and molecular docking proved that the compounds functioned as an effective inhibitor to suppress FtsZ polymerization and FtsZ GTPase activity and thus the compound stops cell division and cause cell death through interacting with C-terminal interdomain cleft of FtsZ.

A molecular fluorescent dye for specific staining and imaging of RNA in live cells: a novel ligand integration from classical thiazole orange and styryl compounds.

A new RNA-selective fluorescent dye integrated with a thiazole orange and a p-(methylthio)styryl moiety shows better nucleolus RNA staining and imaging performance in live cells than the commercial stains. It also exhibits excellent photostability, cell tolerance, and counterstain compatibility with 4',6-diamidino-2-phenylindole for specific RNA-DNA colocalization in bioassays.

Sensitive and selective detection of uracil-DNA glycosylase activity with a new pyridinium luminescent switch-on molecular probe.

Uracil-deoxyribonucleic acid glycosylase (UDG) is known to function as an important base-excision repair enzyme and eliminate uracil from DNA molecules to maintain genomic integrity. A new small organic molecule (DID-VP) with interesting structural properties was synthesized as a G-quadruplex selective ligand and was demonstrated to be a sensitive luminescent switch-on probe in a convenient luminescent assay specifically for UDG detection in fetal bovine serum samples under rapid and simple conditions. This newly developed analytical method is based on the UDG enzymatic activity to unwind a duplex DNA substrate, and comprises a G-quadruplex-forming sequence (ON1) and uracil-containing DNA strand (ON2) to generate a remarkable fluorescence signal through the specific interaction of DID-VP with ON1. This luminescent switch-on assay is able to achieve high sensitivity and specificity for UDG over other enzymes. The application range of the present analytical system is found to be 0.05 to 1.00 U mL(-1) UDG with a very low detection limit of 0.005 U mL(-1). The recovery study of UDG in real samples gave a very good performance with 75.05%-102.7% recovery. In addition, an extended application of the assay in screening of UDG inhibitors is demonstrated. A good dose-dependence of the luminescence response with respect to the concentration of UDG inhibitors in samples was observed.

Improvement of the Immunogenicity of Porcine Circovirus Type 2 DNA Vaccine by Recombinant ORF2 Gene and CpG Motifs.

Nowadays, adjuvant is still important for boosting immunity and improving resistance in animals. In order to boost the immunity of porcine circovirus type 2 (PCV2) DNA vaccine, CpG motifs were inserted. In this study, the dose-effect was studied, and the immunity of PCV2 DNA vaccines by recombinant open reading frame 2 (ORF2) gene and CpG motifs was evaluated. Three-week-old Changbai piglets were inoculated intramuscularly with 200 µg, 400 µg, and 800 µg DNA vaccines containing 14 and 18 CpG motifs, respectively. Average gain and rectum temperature were recorded everyday during the experiments. Blood was collected from the piglets after vaccination to detect the changes of specific antibodies, interleukin-2, and immune cells every week. Tissues were collected for histopathology and polymerase chain reaction. The results indicated that compared to those of the control piglets, all concentrations of two DNA vaccines could induce PCV2-specific antibodies. A cellular immunity test showed that PCV2-specific lymphocytes proliferated the number of TH, TC, and CD3+ positive T-cells raised in the blood of DNA vaccine immune groups. There was no distinct pathological damage and viremia occurring in pigs that were inoculated with DNA vaccines, but there was some minor pathological damage in the control group. The results demonstrated that CpG motifs as an adjuvant could boost the humoral and cellular immunity of pigs to PCV2, especially in terms of cellular immunity. Comparing two DNA vaccines that were constructed, the one containing 18 CpG motifs was more effective. This is the first report that CpG motifs as an adjuvant insert to the PCV2 DNA vaccine could boost immunity.

Effects of gene­activated matrix on autograft healing of anterior cruciate ligament.

The aim of the present study was to observe the effects of gene­activated matrix (GAM) on autograft healing of the anterior cruciate ligament. Forty­eight rabbits were randomly divided into groups A and B. Rabbits were used to construct models of anterior cruciate ligament reconstruction. In group A, transforming growth factor (TGF)­ß1 was locally injected into the bone tunnel, while in group B, empty vector was administered. Tendons were removed to observe histology and ultrastructure and to evaluate biomechanics at postoperative months 1, 3 and 6. Optical microscopy revealed increased numbers of fibroblasts and collagen fibers in group A at each time­point compared with B. Electron microscopy identified increased mitosis and abundance of fibroblasts, endoplasmic reticulum and mitochondria in group A at each time­point compared with B. No significant difference was identified in the biomechanical parameters between the 2 groups at postoperative month 1. At postoperative months 3 and 6, maximum force and elastic modulus were greater in group A compared with group B (P<0.0.5). No significant differences in other biochemical parameters were observed at these time­points. The healing ligament graft transfected with TGF­ß1 by GAM was observed to have improved tissue structure and biomechanical characteristics. The results of the current study may provide a theoretical basis for GAM application in ligament repair.

Heat-shock protein 60 translocates to the surface of apoptotic cells and differentiated megakaryocytes and stimulates phagocytosis.

Heat-shock protein 60 (Hsp60) is a highly conserved stress protein which has chaperone functions in prokaryotes and mammalian cells. Hsp60 is associated with the mitochondria and the plasma membrane through phosphorylation by protein kinase A, and is incorporated into lipid membranes as a protein-folding chaperone. Its diverse intracellular chaperone functions include the secretion of proteins where it maintains the conformation of precursors and facilitates their translocation through the plasma membrane. We report here that Hsp60 is concentrated in apoptotic membrane blebs and translocates to the surface of cells undergoing apoptosis. Hsp60 is also enriched in platelets derived from terminally differentiated megakaryocytes and expressed at the surface of senescent platelets. Furthermore, the exposure of monocytic U937 cells to Hsp60 enhanced their phagocytic activity. Our results suggests that externalized Hsp60 in apoptotic cells and senescent platelets influences events subsequent to apoptosis, such as the clearance of apoptotic cells by phagocytes.

[Role of dendritic cells and their Toll-like receptor 4 in the pathogenesis of idiopathic thrombocytopenic purpura].

OBJECTIVE: To study the surface antigen of the dendritic cells (DC) and their Toll-like receptor 4 (TLR4) expression in patients with idiopathic thrombocytopenic purpura (ITP), and to explore their role in ITP pathogenesis. METHODS: The peripheral blood mononuclear cells isolated from complete remission patients (CR), non-complete remission patients (n-CR) and normal controls were stimulated by rhGM-CSF and rhIL-4. The surface antigen of the DC was analyzed by flow cytometry. The level of IL-12p70 in the supernatant was detected by enzyme linked immunosorbent assay. The expression of TLR4 mRNA of DC was detected by real time PCR. RESULTS: In the 21 CR ITP patients, the expression of both CD80 and CD86 in DC was significantly increased compared with that in normal controls \[(51.60 ± 13.47)% vs (36.03 ± 15.43)%, (61.50 ± 15.93)% vs (40.28 ± 11.49)%, respectively\] (P < 0.01). The expression of CD80 and CD86 in n-CR group was also significantly increased \[(53.29 ± 19.49)% and (62.91 ± 18.43)%, respectively\] (P < 0.01). After HD-DXM treatment, both CD80 and CD86 in CR patients were decreased (P < 0.01). There was no difference between the DXM treatment patients and the normal controls. In n-CR group, there was no difference in CD80 and CD86 expression before and after DXM therapy \[(52.30 ± 20.98% and (49.79 ± 20.28)%, respectively\] (P > 0.05). CD80 was still higher than normal (P < 0.05), while CD86 was not changed. The level of IL-12p70 in CR ITP patients before treatment was significantly higher \[(67.52 ± 14.43) pg/ml\] than that of the controls \[(39.78 ± 10.03) pg/ml\](P < 0.01), and after treatment, was significantly decreased to (43.90 ± 8.49) pg/ml, being no difference from that in control. In n-CR group, IL-12p70 was lower after treatment \[(48.45 ± 9.68) pg/ml\] than that before treatment \[(65.35 ± 12.52) pg/ml\] (P < 0.01), but still higher than that in control (P < 0.05). The TLR4 mRNA level in DCs of CR ITP patients before treatment were significantly higher 0.69 ± 0.17 than that of controls (0.31 ± 0.09) (P < 0.01) and after treatment, was reduced to 0.35 ± 0.11, being no difference from that in control. In n-CR group, TLR4 mRNA was decreased from 0.65 ± 0.09 to 0.52 ± 0.21 after treatment (P < 0.01), but still higher than normal (P < 0.01). CONCLUSION: DC may play an important role in ITP by their Toll-like receptor and cytokine secretion.

Dexamethasone inhibits immunoreactivity of dendritic cells in patients with chronic idiopathic thrombocytopenic purpura.

The objective of this study was to investigate the possible effects of dexamethasone treatment on the immunoreactivity of dendritic cells in patients with chronic idiopathic thrombocytopenic purpura (ITP). Thirty-six newly diagnosed patients with chronic ITP received an oral high dose of dexamethasone (HD-DXM) at single daily doses of 40 mg for 4 consecutive days. The CD14 leukocytes isolated from the 21 remission patients and 10 normal controls were stimulated by recombinant human granulocyte-macrophage colony-stimulating factor and rhIL-4. The surface antigens of the dendritic cells were analyzed by flow cytometry and the level of IL-12p70 in the supernatant was detected by enzyme-linked immunosorbent assay. In ITP patients, the expression of both CD80 and CD86 in dendritic cells were significantly increased compared with those of the normal controls (51.60 +/- 13.47 vs. 36.03 +/- 15.43%, 61.50 +/- 15.93 vs. 40.28 +/- 11.49%, respectively; P < 0.05). After HD-DXM treatment, both CD80 and CD86 were decreased to levels comparable to normal controls (P > 0.05). The level of IL-12p70 in ITP patients was significantly higher (67.52 +/- 14.43 pg/ml) than the controls (39.78 +/- 10.03 pg/ml, P < 0.05). After treatment, IL-12p70 was reduced to 43.90 +/- 8.49 pg/ml with no significant differences between ITP group and control (P > 0.05). Dendritic cells and their cytokine secretion play important roles in ITP, and DXM may achieve its therapeutic effect on ITP by inhibiting immune responses through suppressing the function of dendritic cells.

5-Hydr-oxy-1-methyl-3,4-dihydro-2H-pyrrolium hydrogensulfate.

The title compound, C(5)H(10)NO(+)·HSO(4) (-), has been synthesized by reaction of 1-methyl-pyrrolidin-2-one with H(2)SO(4) in a 1:1 molar ratio. The substituted pyrrolium ring adopts an envelope conformation. The hydrogensulfate anions form infinite helical chains parallel to the a axis via strong O-H⋯O hydrogen bonds. The pyrrolium cations are pendant from the chains. These cations are the hydrogen donors in the strong O-H⋯O hydrogen bonds to the hydrogensulfates. In addition, there are weak C-H⋯O hydrogen bonds in the structure.

[The impact of blood content in skin tissue on skin spectra].

Based on the analysis of skin structure, and the production mechanism of fluorescence and reflectance spectra, six-layer optical models for skin of different blood content in both upper blood plexus and deep blood plexus were developed, and Monte Carlo simulation was made. The result shows that (1) Both fluorescence and reflectance spectra could reflect the change of blood content in skin tissue; (2) The impact of blood content in upper blood plexus on skin spectra intensity is large, while the impact of blood content in deep blood plexus on skin spectra intensity is small; (3) Fluorescence and reflectance spectra could be used to detect or analyze change of blood content in skin tissue, especially to test the treatment and tune of dermatosis with plexus or blood pathological changes in upper dermis.

Correlation of Epstein-Barr virus and its encoded proteins with Helicobacter pylori and expression of c-met and c-myc in gastric carcinoma.

AIM: To investigate the interrelationship of Epstein-Barr virus (EBV) and EBV- encoded proteins with Helicobacter pylori (H pylori) infection and the expression of c-met and c-myc oncogene proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis. METHODS: One hundred and eighty-five gastric carcinoma tissues were detected by polymerase chain reaction (PCR)-Southern blot for EBV genome and in situ hybridization (ISH) for EBV-encoded small RNA 1 (EBER1). Gastric carcinoma with positive EBER1 signals was confirmed EBV-associated gastric carcinoma (EBVaGC). The status of H pylori infection in 185 gastric carcinomas was assessed by rapid urease test and PCR. The samples with positive PCR and urease test were defined as H pylori infection. The expression of c-met and c-myc oncogene proteins in tissues of EBVaGC and matched EBV-negative gastric carcinoma (EBVnGC) were examined by immunohistochemistry. RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens (EBNAs) 1 and 2, latent membrane protein (LMP) 1, early genes BARF1 and BHRF1 in EBVaGC cases. RESULTS: The positive rate of H pylori and EBV in 185 gastric carcinomas was 59.45% (110/185) and 7.03% (13/185) respectively. No difference was found in sex, age, pathological differentiation, clinical stages and lymph node metastasis between H pylori-positive and H pylori-negative gastric carcinomas. However, the positive rate of H pylori infection in the antrum gastric carcinomas was higher than that of cardia and body gastric carcinomas. In our series, age, pathological differentiation, clinical stages, lymph node metastasis and location of cancer were not different between EBVnGC and EBVaGC, while the positive rate of EBV in male patients was significantly higher than that of female patients. The positivity of H pylori in EBV-associated and EBV-negative gastric carcinomas was 46.15% (6/13) and 81.40%(104/172) respectively. There was no significant correlation between EBV and H pylori infection. The c-met overexpression was significantly higher in the EBVaGC group than in the EBVnGC group. However, c-met and c-myc expression did not show significant difference between the two groups. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the 13 cases exhibited BARF1 transcripts and 2 exhibited BHRF1 transcripts. CONCLUSION: The positivity of H pylori in EBVnGCs is higher than that of EBVaGCs, but no significant correlation is found between EBV infection and H pylori infection. H pylori-positive gastric carcinoma is predominant in antrum location, while EBVaGC has a tendency of predominance in cardia/body location. EBV infection is associated with c-met abnormal expression but not with c-myc protein in EBVaGC. c-met overexpression is not induced by LMP1. BARF1 and BHRF1 may play important roles in the tumorigenesis of EBVaGC through different pathways.

Repression of HIP/RPL29 expression induces differentiation in colon cancer cells.

We had previously shown that the expression of heparin/heparan sulfate interacting protein/ribosomal protein L29 (HIP/RPL29) was upregulated in colon cancer tissues. The present study investigated the role of HIP/RPL29 in differentiation in colon cancer cells. Inducing cellular differentiation in HT-29 cells by both sodium butyrate and glucose deprivation resulted in a significant downregulation of HIP/RPL29 expression. The beta-catenin/Tcf-4 pathway is the most important pathway controlling the switch between cellular differentiation and proliferation in intestinal epithelial cells. Inducing differentiation by dominant-negative inhibition of the beta-catenin/Tcf-4 complexes in LS174T cells also resulted in downregulation of HIP/RPL29. To determine whether a lower expression of HIP/RPL29 could induce differentiation in cancer cells, small interfering RNA (siRNA) targeting HIP/RPL29 was transfected into LS174T cells. The resultant knockdown of HIP/RPL29 expression induced cellular differentiation, as shown by the increased expression of two known markers of differentiation in LS174T cells, galectin-4 and mucin-2. In addition, the differentiation process induced by repression of HIP/RPL29 expression was accompanied by the upregulation of p21 and p53. In conclusion, HIP/RPL29 plays a role in the cellular differentiation process in colon cancer cells. The differentiation process is at least partially mediated by the upregulation of p21 and p53 pathways.

Relationship between Epstein-Barr virus-encoded proteins with cell proliferation, apoptosis, and apoptosis-related proteins in gastric carcinoma.

AIM: To investigate the interrelationship between Epstein-Barr virus (EBV)-encoded proteins and cell proliferation, apoptosis and apoptosis-related proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis. METHODS: Tissues from 13 cases of EBV-associated gastric carcinoma (EBVaGC) and 45 cases of matched EBV-negative gastric carcinoma (EBVnGC) were collected, and then subjected to analysis for apoptotic index (AI) using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) assay. Nuclear cell proliferation-associated antigen ki-67 index (KI), bcl-2, and p53 expression were examined by immunohistochemistry. p53 mutation in exons 5-8 of 13 EBVaGC cases was determined by single-strand conformation polymorphism (SSCP) and DNA sequencing. RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens (EBNAs) 1 and 2, latent membrane protein (LMP) 1, immediately early gene BZLF1 and early genes BARF1 and BHRF1 in 13 EBVaGC cases. RESULTS: The percentage of AI, KI and p53 overexpression was significantly lower in the EBVaGC group than in the EBVnGC group. However, bcl-2 expression did not show significant difference between the two groups. p53 gene mutations were not found in 13 EBVaGCs. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the thirteen cases exhibited BZLF1 transcripts and two exhibited BHRF1 transcripts. BARF1 mRNA was detected in six cases. CONCLUSION: Lower AI and KI may reflect a low biological activity in EBVaGC. EBV infection is associated with p53 abnormal expression but not bcl-2 protein in EBVaGC. BZLF1, BARF1, and BHRF1 may play important roles in inhibiting cell apoptosis and tumorigenesis of EBVaGC through different pathways.

Expression of Epstein-Barr virus genes in EBV-associated gastric carcinomas.

AIM: To understand the expression of latent and lytic genes of Epstein-Barr virus (EBV) in EBV-associated gastric carcinoma (EBVaGC) and to explore the relationship between EBV-encoded genes and development of EBVaGC at molecular level. METHODS: One hundred and seventy-two gastric carcinoma tissues and 172 corresponding para-carcinoma tissues were tested for EBV genome by polymerase chain reaction (PCR)-Southern blotting. EBV-encoded small RNA (EBER) 1 of the PCR positive specimens was detected by in situ hybridization (ISH). Gastric carcinomas with positive EBER1 signals were classified as EBVaGCs. RT-PCR and Southern hybridization were applied to the detection of expression of nuclear antigen (EBNA) promoters (Qp, Wp and Cp), EBNA 1 and EBNA 2, latent membrane proteins (LMP) 1, 2A and 2B and lytic genes (immediate early genes BZLF1 and BRLF1, early genes BARF1 and BHRF1, late genes BcLF1 and BLLF1) in EBVaGCs. RESULTS: Eleven EBV positive samples existed in gastric carcinoma tissues (6.39%). No EBV positive sample was found in corresponding para-carcinoma tissues. The difference between EBV positivity in carcinoma tissues and corresponding para-carcinoma tissues was significant (chi(2) = 9.0909, P = 0.0026). Transcripts of Qp and EBNA1 were detected in all the 11 EBVaGCs, while both Wp and Cp were silent. EBNA2, LMP1 and LMP2B mRNA were absent in all the cases, while LMP2A mRNA was detected in 4 of the 11 cases. Of the 11 EBVaGCs, 7 exhibited BcLF1 transcripts and 2 exhibited BHRF1 transcripts. The transcripts of BZLF1 and BARF1 were detected in 5 cases, respectively. No BLLF1 and BRLF mRNA were detected. CONCLUSION: The latent pattern of EBV in gastric carcinoma corresponds to the latency I/II. Some lytic infection genes are expressed in EBVaGCs tissues. BARF1 and BHRF1 genes may play an important role in tumorigenesis of gastric carcinoma.

[Expression of Epstein-Barr virus genes in EBV-associated gastric carcinoma].

BACKGROUND & OBJECTIVE: Epstein-Barr virus (EBV) is associated with the development of many malignant tumors. The forms of EBV and the expression of EBV genes in Burkitt's lymphoma and nasopharyngeal carcinoma (NPC) have been reported. These studies showed that the forms of EBV and the expression of EBV genes are various in different types of malignancies. However, there were only a few reports about the expression of EBV genes, especially the lytic genes, in gastric carcinoma tissues. This study was to determine the expression of EBV latent and lytic infection genes in gastric carcinoma at the transcriptional level by RT-PCR and Southern hybridization,and investigate the relationship between EBV-encoded genes and the tumorigenesis of gastric carcinoma at the molecular level. METHODS: One hundred and eighty-five gastric carcinoma and corresponding para-carcinoma tissues were tested for EBV genome by polymerase chain reaction (PCR)-Southern analysis. EBV-encoded small RNA 1 (EBER1) of the PCR positive specimens was determined by in situ hybridization (ISH). Gastric carcinoma with positive EBER1 signals was confirmed EBV- associated gastric carcinoma (EBVaGC). RT-PCR and Southern hybridization were used to determine the expression of nuclear antigen (EBNA) promoters (Qp, Wp and Cp), EBNA 1 and 2,latent membrane protein (LMP) 1, 2A, and 2B and lytic genes (immediate-early genes BZLF1 and BRLF1, early genes BARF1 and BHRF1, late genes BcLF1 and BLLF1) in EBVaGCs. RESULTS: There were 13 EBV positive samples in gastric carcinomas (7.03%), but no EBV positive sample in corresponding para-carcinomas. The transcripts of Qp were detected in all of the 13 EBVaGCs tissues, while both Wp and Cp were silent. All of the 13 cases expressed EBNA1 mRNA, but no EBNA2, LMP1, and LMP2B mRNA. LMP2A mRNA was detected in 5 of the 13 cases. Of the 13 EBVaGCs, 7 exhibited BcLF1 transcript and 2 exhibited BHRF1 transcript. The transcripts of BZLF1 were detected in 6 cases, and those of BARF1 also in 6 cases. No BLLF1 and BRLF mRNA were detected in the 13 EBVaGCs. CONCLUSIONS: The latent pattern of EBV in EBVaGCs corresponds to the latency I or unique latency I/II, intermediate between the latency I and II. Part of lytic infection genes are expressed in EBVaGCs tissues. BARF1 and BHRF1 genes express in part of gastric carcinomas and their roles in gastric tumorigenesis need to be further studied.