Tre2 (USP6NL) promotes colorectal cancer cell proliferation via Wnt/ß-catenin pathway.

BACKGROUND: Most colorectal cancer (CRC) patients are diagnosed at an advanced or metastatic stage with poor prognosis. Ubiquitin-specific protease 6 N-terminal-like protein (USP6NL) with high expression in CRC tissues regulates CRC cell proliferation via Wnt/ß-catenin pathway. We hypothesized that USP6NL impacts CRC growth and inhibition of USP6NL may be a novel treatment strategy to improve CRC therapy. METHODS: USP6NL level in human CRC tissues and its association with tumor growth and metastasis were examined. Its roles and potential mechanisms in regulating tumor growth were studied by genetic and pharmacological manipulation of CRC cells in vitro and in vivo. RESULTS: Herein, we found that USP6NL was up-regulated in tumorous tissues of CRC patients. Our data suggested that knockdown of USP6NL in human CRC cell lines (HCT116 and LOVO cells) inhibited cell proliferation, induced G0/G1 cell cycle arrest, and prevented the tumorigenicity of HCT116 cells in nude mice, and which was associated with the prevention of Wnt/ß-catenin pathway. On the contrary, USP6NL overexpression in human CRC cells (SW480) showed the opposite result. Our data suggested that the promoted cell proliferation, G1/S cell cycle progression, and the enhanced expression of ß-catenin Cyclin D1 and C-myc while reduced P27 induced by the overexpression of USP6NL were significantly reversed by additional treatment of XAV939, indicating that activating Wnt/ß-catenin pathway was the mechanism, by which USP6NL exerted carcinogenesis in CRC in vitro. Besides, our data suggested that knockdown of USP6NL increased the ubiquitination of ß-catenin, indicating that USP6NL may serve as a deubiquitinase that regulated ß-catenin accumulation in this process. Furthermore, 10058-F4 down-regulated USP6NL, inhibited CRC cell proliferation and induced cell cycle arrest. The result demonstrated a possible feedback loop between USP6NL, ß-catenin and C-myc in regulating CRC cell growth. CONCLUSION: USP6NL was an oncogene in CRC, and it may be a potential target for the treatment of CRC.

A study of relationship between social support, work values and job search behavior.

The COVID-19 outbreak has put more pressure on the labor market, reducing employment opportunities and increasing graduate unemployment. Therefore, this study was undertaken to explore the relationship between social support, work values and job search behavior. The theoretical model was tested using the data collected from 560 Chinese fresh graduates (Mage = 23.45 years; standard deviation = 2.02). The participants completed questionnaires that assessed their social support, work values and job search behavior. Descriptive statistics and structural equation modeling were used for data analysis. The results indicated that social support was positively and directly associated job search behavior and work value mediated the association between social support and job search behavior. These findings will encourage future researchers to investigate the phenomena of job search behavior.

Intranasal vaccination with a helper-dependent adenoviral vector enhances transgene-specific immune responses in BALB/c mice.

Helper-dependent adenoviral (HDAd) vectors were developed primarily for genetic disease therapy by deleting all coding regions for attenuating the host cellular immune response to adenovirus (Ad) and long-lasting gene expression. Recently Harui et al. reported that HDAd vaccine could stimulate superior transgene-specific cytotoxic T lymphocyte (CTL) and antibody responses via the intraperitoneal route, compared to first-generation adenoviral (FGAd) vaccine. This prompted us to explore the potential of HDAd as a vaccine vector administrated intranasally. In this study, we prepared HDAd and FGAd vectors expressing enhanced green fluorescent protein (EGFP), respectively, and compared their efficacy in mice. Mice were immunized intranasally with 5x10(9) vp HDAd or FGAd vector particles. Despite stimulating similar anti-Ad antibody responses with FGAd vaccine in the prime/boost strategy, HDAd vector expressing EGFP displayed superior transgene-specific serum IgG, mucosal IgA and cellular immune response, with the characterization of balanced or mixed Th1/Th2 CD4+ T-cell responses. Meanwhile, a single dose of intranasal (i.n.) vaccine of HDAd-EGFP induced a serum IgG response with more efficacy than FGAd-EGFP. In addition, i.n. boost immunization enhanced transgene-specific humoral and cellular responses, compared to single i.n. HDAd-EGFP immunization. Our results suggest that HDAd has potential for a mucosal vaccine vector via i.n. route, which will be useful for the development of vaccines against respiratory viruses, such as respiratory syncytial virus and influenza virus.

A prime-boost vaccination strategy using attenuated Salmonella typhimurium and a replication-deficient recombinant adenovirus vector elicits protective immunity against human respiratory syncytial virus.

Human respiratory syncytial virus (RSV), for which no clinically approved vaccine is available yet, is globally a serious pediatric pathogen of the lower respiratory tract. Several approaches have been used to develop vaccines against RSV, but none of these have been approved for use in humans. An efficient vaccine-enhancing strategy for RSV is still urgently needed. We found previously that oral SL7207/pcDNA3.1/F and intranasal FGAd/F were able to induce an effective protective immune response against RSV. The heterologous prime-boost immunization regime has been reported recently to be an efficient vaccine-enhancing strategy. Therefore, we investigated the ability of an oral SL7207/pcDNA3.1/F prime and intranasal (i.n.) FGAd/F boost regimen to generate immune responses to RSV. The SL7207/pcDNA3.1/F prime-FGAd/F boost regimen generated stronger RSV-specific humoral and mucosal immune responses in BALB/c mice than the oral SL7207/pcDNA3.1/F regimen alone, and stronger specific cellular immune responses than the i.n. FGAd/F regimen alone. Histopathological analysis showed an increased efficacy against RSV challenge by the heterologous prime-boost regimen. These results suggest that such a heterologous prime-boost strategy can enhance the efficacy of either the SL7207 or the FGAd vector regimen in generating immune responses in BALB/c mice.

Novel recombinant adenovirus type 41 vector and its biological properties.

BACKGROUND: Human adenovirus serotype 41 (Ad41) is a natural pathogen of the digestive tract and can cause gastroenteritis. There has been interest in reconstructing Ad41 as a gene delivery vector targeting the gastrointestinal tract, which is hampered by its fastidiousness. METHODS: An Ad41 E1B55K-transduced 293 cell line (293E12) was established as the packaging cell line. A backbone plasmid (pAdbone41) and a shuttle plasmid (pSh41-CMV) were constructed based on the Ad41 genome. Replication-defective adenovirus (Ad41-GFP) was rescued in 293E12 after being transfected with the linearized adenoviral plasmid, which was generated by homologous recombination of pAdbone41 and the shuttle plasmid carrying the GFP gene in Escherichia coli strain BJ5183. The packaging ability of 293E12, the stability of the Ad41-GFP genome and the acid-resistant property of Ad41-GFP were all investigated. RESULTS: A 293E12 cell could produce approximately 9000 viral particles of Ad41-GFP, which is close to the amount in the control virus (Ad5-GFP) amplified in one 293 cell. Ad41-GFP contained a genetically stable genome after being passaged eight times in 293E12 cells. More significantly, Ad41-GFP was more resistant to acid exposure than Ad5-GFP. It retained almost complete viability when exposed to hydrochloric acid with a pH value of 2 for 30 min, whereas Ad5-GFP lost 99% of its viability under the same conditions. Ad41-GFP was also more tolerant to treatment with artificial digestive fluid. CONCLUSIONS: An Ad41 vector system was successfully constructed, which consisted of the backbone plasmid, shuttle plasmid and packaging cell line 293E12. This system can be utilized to generate genetically stable and acid-resistant recombinant Ad41 carrying any gene of interest.

Dynamic changes of IL-2/IL-10, sFas and expression of Fas in intestinal mucosa in rats with acute necrotizing pancreatitis.

AIM: To investigate dynamic changes of serum IL-2, IL-10, IL-2/IL-10 and sFas in rats with acute necrotizing pancreatitis. To explore the expression of Fas in intestinal mucosa of rats with acute necrotizing pancreatitis (ANP). METHODS: A total of 64 Sprague-Dawley (SD) rats were randomly divided into two groups: normal control group (C group), ANP group (P group). An ANP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane. Normal control group received isovolumetric injection of 9 g/L physiological saline solution using the same method. The blood samples of the rats in each group were obtained via superior mesenteric vein to measure levels of IL-2, IL-10, sFas and calculate the value of IL-2/IL-10. The levels of IL-2, IL-10 and sFas were determined by ELISA. The severity of intestinal mucosal injury was evaluated by pathologic score. The expression of Fas in intestinal mucosal tissue was determined by immunohistochemistry staining. RESULTS: Levels of serum IL-2 were significantly higher in P group than those of C group (2.79 +/- 0.51 vs 3.53 +/- 0.62, 2.93 +/- 0.89 vs 4.35 +/- 1.11, 4.81 +/- 1.23 vs 6.94 +/- 1.55 and 3.41 +/- 0.72 vs 4.80 +/- 1.10, respectively, P < 0.01, for all) and its reached peak at 6 h. Levels of serum IL-10 were significantly higher in P group than those of C group at 6 h and 12 h (54.61 +/- 15.81 vs 47.34 +/- 14.62, 141.15 +/- 40.21 vs 156.12 +/- 43.10, 89.18 +/- 32.52 vs 494.98 +/- 11.23 and 77.15 +/- 22.60 vs 93.28 +/- 25.81, respectively, P < 0.01, for all). The values of IL-2/IL-10 were higher significantly in P group than those of C group at 0.5 h and 2 h (0.05 +/- 0.01 vs 0.07 +/- 0.02 and 0.02 +/- 0.01 vs 0.03 +/- 0.01, respectively, P < 0.01, for all), and it were significantly lower than those of C group at 6 h (0.05 +/- 0.02 vs 0.01 +/- 0.01, P < 0.01) and returned to the control level at 12 h (0.04 +/- 0.01 vs 0.05 +/- 0.02, P > 0.05). In sFas assay, there was no significant difference between P group and C group (3.16 +/- 0.75 vs 3.31 +/- 0.80, 4.05 +/- 1.08 vs 4.32 +/- 1.11, 5.93 +/- 1.52 vs 5.41 +/- 1.47 and 4.62 +/- 1.23 vs 4.44 +/- 1.16, respectively, P > 0.05, for all). Comparison of P group and C group, the pathological changes were aggravated significantly in P group. Immunohistochemistry staining show the expression of Fas was absent in normal intestinal tissues, however, it gradually increased after induction of pancreatitis in intestinal tissue, then reached their peaks at 12 h. CONCLUSION: Fas were involved in the pathogenesis of pancreatitis associated intestinal injury. The mechanisms of Fas may be associated to Fas mediated T helper cell apoptosis.

PLK1 as a potential prognostic marker of gastric cancer through MEK-ERK pathway on PDTX models.

BACKGROUND: PLK1 has been identified as having a great effect on cell division and maintaining genomic stability in mitosis, spindle assembly, and DNA damage response by current studies. MATERIALS AND METHODS: We assessed PLK1 expression in cervical cancer tissues and cells. We have also evaluated the effects of PLK1 on gastric cancer cell proliferation, migration, and apoptosis both in vitro and in vivo. RESULTS: Our results show that PLK1 is overexpressed in gastric cancer tissues and cells. Inhibition of PLK1 contributes cell cycle G2-phase arrest and inhibits the proliferation, migration, and apoptosis of gastric cancer (GC) cells, whereas its overexpression promotes proliferation, migration, and apoptosis in these cells. Moreover, PLK1 inhibition reduces expression of pMEK and pERK. More importantly, in vivo by analyzing tumorigenesis in patient-derived tumor xenograft (PDTX) models, the inhibition of PLK1 activity by BI6727 significantly decreased the volume and weight of the tumors compared with control group (P<0.01). CONCLUSION: Our results found that PLK1 has a significant impact on the survival of GC cells; it may become a prognostic judge, a potential therapeutic target, and a preventative biomarker of GC.

Suppression of human colon tumor growth by adenoviral vector-mediated NK4 expression in an athymic mouse model.

AIM: To investigate the suppressive effects of adenoviral vector-mediated expression of NK4, an antagonist of hepatocyte growth factor (HGF), on human colon cancer in an athymic mouse model to explore the possibility of applying NK4 to cancer gene therapy. METHODS: A human colon tumor model was developed by subcutaneous implantation of tumor tissue formed by LS174T cells grown in athymic mice. Fifteen tumor-bearing mice were randomized into three groups (n = 5 in each group) at d 3 after tumor implantation and mice were injected intratumorally with phosphate-buffered saline (PBS) or with recombinant adenovirus expressing beta-galactosidase (Ad-LacZ) or NK4 (rvAdCMV/NK4) at a 6-d interval for total 5 injections in each mouse. Tumor sizes were measured during treatment to draw a tumor growth curve. At d 26 after the first treatment, all animals were sacrificed and the tumors were removed to immunohistochemically examine proliferating cell nuclear antigen (PCNA), microvessel density (represented by CD31), and apoptotic cells. In a separate experiment, 15 additional athymic mice were employed to develop a tumor metastasis model by intraperitoneal injection (ip) of LS174T cells. These mice were randomized into 3 groups (n = 5 in each group) at d 1 after injection and were treated by ip injection of PBS, or Ad-LacZ, or rvAdCMV/NK4 at a 6-d interval for total two injections in each mouse. All animals were sacrificed at d 14 and the numbers and weights of disseminated tumors within the abdominal cavity were measured. RESULTS: Growth of human colon tumors were significantly suppressed in the athymic mice treated with rvAdCMV/NK4 (2537.4 +/- 892.3 mm(3)) compared to those treated by either PBS (5175.2 +/- 1228.6 mm(3)) or Ad-LacZ (5578.8 +/- 1955.7 mm(3)) (P < 0.05). The tumor growth inhibition rate was as high as 51%. Immunohistochemical staining revealed a similar PCNA labeling index (75.1% +/- 11.2% in PBS group vs 72.8% +/- 7.6% in Ad-LacZ group vs 69.3% +/- 9.4% in rvAdCMV/NK4 group) in all groups, but significantly lower microvessel density (10.7 +/- 2.4 in rvAdCMV/NK4 group vs 25.6 +/- 3.8 in PBS group or 21.3 +/- 3.5 in Ad-LacZ group, P < 0.05), and a markedly higher apoptotic index (7.3% +/- 2.4% in rvAdCMV/NK4 group vs 2.6 +/- 1.1% in PBS group or 2.1% +/- 1.5% in Ad-LacZ group, P < 0.05) in the rvAdCMV/NK4 group compared to the two control groups. In the tumor metastasis model, the number and weight of disseminated tumors of mice treated with rvAdCMV/NK4 were much lower than those of the control groups (tumor number: 6.2 +/- 3.3 in rvAdCMV/NK4 group vs 22.9 +/- 7.6 in PBS group or 19.8 +/- 8.5 in Ad-LacZ group, P < 0.05; tumor weight: 324 +/- 176 mg in rvAdCMV/NK4 group vs 962 +/- 382 mg in PBS group or 1116 +/- 484 mg in Ad-LacZ group, P < 0.05). CONCLUSION: The recombinant adenovirus, rvAdCMV/NK4, can attenuate the growth of colon cancer in vivo, probably by suppressing angiogenesis and inducing tumor cell apoptosis, but not by direct suppression of tumor cell proliferation. Moreover, rvAdCMV/NK4 may inhibit peritoneal dissemination of colon cancer cells in a murine tumor metastasis model. These findings indicate that NK4 gene transfer may be an effective tool for the treatment of colon cancer.

Ligustrazine alleviates gastric mucosal injury in a rat model of acute necrotizing pancreatitis.

BACKGROUND: Acute necrotizing pancreatitis (ANP) leads to a systemic inflammatory response characterized by widespread leukocyte activation and, as a consequence, distant organ injury. The aim of this study was to explore the relationship between gastric microcirculatory impairment and inflammatory mediators released in rats and to evaluate the therapeutic effect of ligustrazine extracted from Rhizoma ligusticum wallichii on gastric mucosa injury in a rat model of ANP. METHODS: Ninety-six Sprague-Dawley rats were randomly divided into three groups: normal control (group C); ANP without treatment (group P); and ANP treated with ligustrazine (group T). The ANP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane (4 ml/kg). Group C was given isovolumetric injection of 9 g/L physiological saline by the same route. Group T was injected with ligustrazine (10 ml/kg) via the portal vein. The radioactive biomicrosphere technique was used to measure the blood flow 2 and 12 hours after the induction of ANP. Samples of the pancreas and stomach were taken to assess pathological changes by a validated histology score; meanwhile, the levels of serum interleukin-1beta (IL-1beta) were determined. Gastric tissues were also used to measure the level of myeloperoxidase (MPO), which is expressed intracellularly in the azurophilic granules of neutrophils. RESULTS: Blood flow in group P was significantly lower than that in group C (P<0.01). Pathological changes were significantly aggravated in group P. The gastric MPO activity in group P was significantly higher than that in group C (P<0.01). The level of serum IL-1beta in group P increased more significantly than that in group C (P<0.01). Blood flow of the stomach in group T was significantly higher than that in group P after 2 hours (P<0.01). The pathological changes were significantly alleviated in group T. The MPO activity of group T was significantly lower than that of group P (P<0.01). Although serum IL-1beta level of group T was higher than of group C (P<0.01), it was lower than that of group P (P<0.01). There was a negative correlation between gastric blood flow and MPO activity (r=-0.983, P<0.01), and between gastric blood flow and pathological score (r=-0.917, P<0.05). CONCLUSIONS: Decreased gastric blood flow and increased inflammatory mediators can be seen early in ANP, and both are important factors for gastric and mucosal injury. Ligustrazine can ameliorate microcirculatory disorder and alleviate the damage to the pancreas and stomach.

Giant mucinous adenocarcinoma of the appendix: a case report.

BACKGROUND: Appendiceal mucinous adenocarcinoma is an extremely rare disease in clinical practice. Here, we report a case of unprecedented size that occupied the entire abdomen of a man. CASE PRESENTATION: A 49-year-old Chinese Han man presented with symptoms of abdominal distension. During a computed tomography imaging examination, a cystic-solid mass that occupied his entire abdominal cavity was detected. During exploratory laparotomy, an appendiceal tumor in his abdominal-pelvic cavity measuring 27.6 × 14.2 cm was found, and he underwent tumor resection. The pathology of the tumor identified a well-differentiated appendiceal mucinous adenocarcinoma with mucin infiltrating into the soft tissue of the lump edge and omentum tissue. After surgery, our patient accepted intraperitoneal infusion chemotherapy. At present, he has had no recurrence for 15 months. CONCLUSIONS: To the best of our knowledge, the present case is the largest appendiceal mucinous adenocarcinoma reported. Surgical tumor resection is the preferred treatment for appendiceal mucinous adenocarcinoma. This is supplemented by chemotherapy which can further prolong survival.

Ligustrazine alleviates acute renal injury in a rat model of acute necrotizing pancreatitis.

AIM: To evaluate the effect of ligustrazine, a traditional Chinese medicine, on renal injury in a rat model of acute necrotizing pancreatitis (ANP). METHODS: A total of 192 rats were randomly divided into three groups: control (C group), ANP without treatment (P group), and ANP treated with ligustrazine (T group). Each group was further divided into 0.5, 2, 6, 12 h subgroups. All rats were anesthetized with an intraperitoneal injection of sodium pentobarbital. Sodium taurocholate was infused through the pancreatic membrane to induce ANP. T group was infused sodium taurocholate as above, and 0.6% ligustrazine was then administered via the femoral vein. Serum urea nitrogen (BUN) and creatinine (Cr) concentrations were measured for the evaluation of renal function. The effects of ligustrazine on the severity of renal injury were assessed by renal function, TXA(2)/PGI(2) and histopathological changes. Renal blood flow was determined by the radioactive microsphere technique (RMT). RESULTS: Compared with control group, the renal blood flow in P group was decreased significantly. Serious renal and pancreatic damages were found in P group, the BUN and Cr levels were elevated significantly, and the ratio of TXA(2) to PGI(2) was increased at 2, 6 and 12 h. Compared with P group, the blood flow of kidney was elevated significantly at 6 and 12 h after induction of ANP, the renal and pancreatic damages were attenuated, and the BUN and Cr levels were decreased significantly, and the ratio of TXA(2) to PGI(2) was decreased at 6 and 12 h in T group. CONCLUSION: Microcirculatory disorder (MCD) is an important factor for renal injury in ANP. Ligustrazine can ameliorate the condition of MCD and the damage of pancreas and kidney.

Preventive effect of tetramethylpyrazine on intestinal mucosal injury in rats with acute necrotizing pancreatitis.

AIM: To evaluate the role of microcirculatory disorder (MCD) and the therapeutic effectiveness of tetramethylpyrazine (TMP) on intestinal mucosa injury in rats with acute necrotizing pancreatitis (ANP). METHODS: A total of 192 Sprague-Dawley rats were randomly divided into three groups: normal control group (C group), ANP group not treated with TMP (P group), ANP group treated with TMP (T group). An ANP model was induced by injection of 50 g/L sodium taurocholate under the pancreatic membrane (4 mL/kg). C group received isovolumetric injection of 9 g/L physiological saline solution using the same method. T group received injection of TMP (10 mL/kg) via portal vein. Radioactive biomicrosphere technique was used to measure the blood flow at 0.5, 2, 6 and 12 h after the induction of ANP. Samples of pancreas, distal ileum were collected to observe pathological changes using a validated histology score. Intestinal tissues were also used for examination of myeloperoxidase (MPO) expressed intracellularly in azurophilic granules of neutrophils. RESULTS: The blood flow was significantly lower in P group than in C group (P < 0.01). The pathological changes were aggravated significantly in P group. The longer the time, the severer the pathological changes. The intestinal MPO activities were significantly higher in P group than in C group (P < 0.01). The blood flow of intestine was significantly higher in T group than in P group after 2 h (P < 0.01). The pathological changes were alleviated significantly in T group. MPO activities were significantly lower in T group than in P group (P < 0.01 or P < 0.05). There was a negative correlation between intestinal blood flow and MPO activity (r = -0.981, P < 0.01) as well as between intestinal blood flow and pathologic scores (r = -0.922, P < 0.05). CONCLUSION: MCD is an important factor for intestinal injury in ANP. TMP can ameliorate the condition of MCD and the damage to pancreas and intestine.

Effects of adenoviral-mediated gene transduction of NK4 on proliferation, movement, and invasion of human colonic LS174T cancer cells in vitro.

AIM: To investigate the inhibitory effects of a recombinant adenovirus vector that expresses NK4, a truncated form of human hepatocyte growth factor (HGF), on human colonic adenocarcinoma cells in vitro to establish a basis for future NK4 gene cancer therapy. METHODS: Cells from the LS174T human colonic adenocarcinoma cell line were infected with recombinant adenovirus rvAdCMV/NK4 and the effects of the manipulation on tumor cell proliferation, scatter, migration, and basement membrane invasion were assessed. Cells infected with a recombinant adenovirus vector (Ad-LacZ) expressing beta-galactosidase served as the controls. RESULTS: We found that rvAdCMV/NK4 expression attenuated HGF-induced tumor cell scatter, migration, and basement membrane invasion (P<0.05), but did not inhibit tumor cell proliferation. CONCLUSION: HGF-induced LS174T tumor cell scatter, migration, and invasion can be antagonized by the recombinant NK4-expressing adenovirus.

IRF5 regulates lung macrophages M2 polarization during severe acute pancreatitis in vitro.

AIM: To investigate the role of interferon regulatory factor 5 (IRF5) in reversing polarization of lung macrophages during severe acute pancreatitis (SAP) in vitro. METHODS: A mouse SAP model was established by intraperitoneal (ip) injections of 20 µg/kg body weight caerulein. Pathological changes in the lung were observed by hematoxylin and eosin staining. Lung macrophages were isolated from bronchoalveolar lavage fluid. The quantity and purity of lung macrophages were detected by fluorescence-activated cell sorting and evaluated by real-time polymerase chain reaction (RT-PCR). They were treated with IL-4/IRF5 specific siRNA (IRF5 siRNA) to reverse their polarization and were evaluated by detecting markers expression of M1/M2 using RT-PCR. RESULTS: SAP associated acute lung injury (ALI) was induced successfully by ip injections of caerulein, which was confirmed by histopathology. Lung macrophages expressed high levels of IRF5 as M1 phenotype during the early acute pancreatitis stages. Reduction of IRF5 expression by IRF5 siRNA reversed the action of macrophages from M1 to M2 phenotype in vitro. The expressions of M1 markers, including IRF5 (S + IRF5 siRNA vs S + PBS, 0.013 ± 0.01 vs 0.054 ± 0.047, P < 0.01), TNF-α (S + IRF5 siRNA vs S + PBS, 0.0003 ± 0.0002 vs 0.019 ± 0.018, P < 0.001), iNOS (S + IRF5 siRNA vs S + PBS, 0.0003 ± 0.0002 vs 0.026 ± 0.018, P < 0.001) and IL-12 (S + IRF5 siRNA vs S + PBS, 0.000005 ± 0.00004 vs 0.024 ± 0.016, P < 0.001), were decreased. In contrast, the expressions of M2 markers, including IL-10 (S + IRF5 siRNA vs S + PBS, 0.060 ± 0.055 vs 0.0230 ± 0.018, P < 0.01) and Arg-1 (S + IRF5 siRNA vs S + PBS, 0.910 ± 0.788 vs 0.0036 ± 0.0025, P < 0.001), were increased. IRF5 siRNA could reverse the lung macrophage polarization more effectively than IL-4. CONCLUSION: Treatment with IRF5 siRNA can reverse the pancreatitis-induced activation of lung macrophages from M1 phenotype to M2 phenotype in SAP associated with ALI.

Changes of gastric and intestinal blood flow, serum phospholipase A2 and interleukin-1beta in rats with acute necrotizing pancreatitis.

AIM: To explore the relationship between gastric and intestinal microcirculatory impairment and inflammatory mediators released in rats with acute necrotizing pancreatitis (ANP). METHODS: A total of 64 rats were randomized into control group and ANP group. ANP model was induced by injection of 5% sodium taurocholate under the pancreatic membrane. Radioactive biomicrosphere technique was used to measure the gastric and intestinal tissue blood flow at 2 and 12 h after the induction of ANP, meanwhile serum phospholipase A2 (PLA2) activities and interleukin-1beta levels were determined. Pathologic changes in pancreas, gastric and intestinal mucosae were studied. RESULTS: The gastric blood flow in ANP group (0.62+/-0.06 and 0.35+/-0.05) mL/(min.g) was significantly lower than that in control group (0.86+/-0.11 and 0.85+/-0.06) mL/(min.g) (P<0.01) at 2 and 12 h after induction of ANP. The intestinal blood flow in ANP group (0.80+/-0.07 and 0.50+/-0.06) mL/(min.g) was significantly lower than that in control group (1.56+/-0.18 and 1.61+/-0.11) mL/(min.g) (P<0.01). Serum PLA2 activities (94.29+/-9.96 and 103.71+/- 14.40) U/L and IL-1beta levels (0.78+/-0.13 and 0.83+/-0.20) microg/L in ANP group were higher than those in control group (65.27+/-10.52 and 66.63+/-9.81) U/L, (0.32+/-0.06 and 0.33+/-0.07) betag/L (P<0.01). At 2 and 12 h after introduction of the model, typical pathologic changes were found in ANP. Compared with control group, the gastric and intestinal mucosal pathologic changes were aggravated significantly (P<0.01) at 12 h after induction of ANP. Gastric and intestinal mucosal necrosis, multiple ulcer and hemorrhage occurred. CONCLUSION: Decrease of gastric and intestinal blood flow and increase of inflammatory mediators occur simultaneously early in ANP, both of them are important pathogenic factors for gastric and intestinal mucosal injury in ANP.

[Soluble of Metals within TSP in Shanghai].

The dissolution of metals within aerosol particles is meaningful to evaluate the bioavailability and mobility of metals. Total suspended particles (TSP) samples were collected in Shanghai. We extracted the water soluble and acid soluble (pH = 2) metals by the mini-recirculation-leach-system and measured their concentrations by the high resolution inductively coupled plasma mass spectrometry. The dissolution kinetics were rapid, the maximum solubility of metals could be reached in a few minutes. Overall, the average water-soluble concentrations were low for Co, Cr, Cd, V and Ni, median for Cu, Pb and Mn and high for Fe, Al, Zn and Mg. Combine the soluble metal concentrations with the back trajectory, the original air mass had significant impacts on water soluble metal concentrations. The water solubility and acid solubility were different for various metals, the water solubility of Fe was the lowest (2.0%), others followed an order: Al, Cr, V, Pb, Co, Ni, Cu, Cd, Mn, Mg, Zn. The metals' solubility was increased with the decrease of the solvent pH value. While the chemical speciation of metals was the internal cause of metals' solubility, the metals' ionic potential and the water solubility was negatively correlated.

Are gastric mucosal macrophages responsible for gastric injury in acute pancreatitis?

AIM: To investigate the protective effect of clodronate-containing liposomes against severe acute pancreatitis (SAP)-triggered acute gastric mucosal injury (AGMI) in rats. METHODS: Clodronate- and phosphate-buffered saline (PBS)-containing liposomes were prepared by reverse-phase evaporation. The SAP rat model was established by injecting sodium taurocholate into the pancreatic subcapsular space. Sprague-Dawley rats were randomly divided into three groups: control (C), SAP plus PBS-containing liposome (P) and SAP plus clodronate-containing liposome (T). Serum tumor necrosis factor (TNF)-α levels were estimated by ELISA. Pathological changes in the gastric mucosa and pancreas were observed by hematoxylin and eosin (HE) staining. Apoptotic cells were detected by terminal deoxynucleotidyl transferase dUTP nick end labeling staining. The numbers of macrophages in the gastric mucosa were analyzed by CD68 immunohistochemical staining. RESULTS: The liposomes had a mean diameter of 150 ± 30 nm. The TNF-α levels were significantly higher in the P group than that in the C group (2 h, 145.13 ± 11.50 vs 23.2 ± 2.03; 6 h, 245.06 ± 12.11 vs 30.28 ± 6.07, P < 0.05), and they were significantly lower in the T group than that in the P group (2 h, 93.24 ± 23.11 vs 145.13 ± 11.50; 6 h, 135.18 ± 13.10 vs 245.06 ± 12.11, P < 0.05). The pathological scores of the pancreas were lower in the T group than in the P group (2 h, 1.88 ± 0.83 vs 4.13 ± 0.83; 6 h, 2.87 ± 0.64 vs 6.25 ± 0.88, P < 0.01). The pathological scores of the gastric mucosa were also lower in the T group than in the P group (2 h, 1.12 ± 0.64 vs 2 ± 0.75; 6 h, 1.58 ± 0.53 vs 3 ± 1.31, P < 0.05). In addition, increased CD68 levels were observed in the gastric mucosa of the P group compared with the C group. Clodronate-containing liposomes decreased the CD68 levels in the mucosa of the T group. The apoptotic indexes of the gastric mucosa were higher in the T group than in the P group (2 h, 15.7 ± 0.92 vs 11.5 ± 1.64; 6 h, 21.12 ± 1.06 vs 12.6 ± 2.44, P < 0.01). CONCLUSION: Gastric macrophages contribute to the pathogenesis of gastric injury in SAP. Clodronate-containing liposomes have protective effects against AGMI in rats with SAP.

[Chlamydia-like and coronavirus-like agents found in dead cases of atypical pneumonia by electron microscopy].

OBJECTIVE: To explore the causative agents of the atypical pneumonia (also SARS) occurred recently in some regions of our country. METHOD: Organ samples of 7 dead cases of SARS were collected from Guangdong, Shanxi, Sichuan Provinces and Beijing for electron microscopic examination. 293 cell line was inoculated with the materials derived from the lungs to isolate causative agent(s). The agents in the organs and cell cultures were revealed by immunoassay. RESULTS: Both Chlamydia-like and coronavirus-like particles were found in EM. Inclusion bodies containing elementary bodies, reticulate antibodies and intermediate bodies of Chlamydia-like agent were visualized in multiple organs from the 7 dead cases, including lungs (7 cases), spleens (2 cases), livers (2 cases), kidneys (3 cases) and lymph nodes (1 cases), by ultrathin section electron microscopy (EM). In some few sections, coronavirus-like particles were concurrently seen. A coronavirus RNA- polymerase segment (440 bp) was amplified from the lung tissues of two cases of the SARS. After inoculated with materials from the lung samples, the similar Chlamydia-like particles were also found in the inoculated 293 cells. Since the Chlamydia-like agents visualized in both organs and cell cultures could not react with the genus specific antibodies against Chlamydia and monoclonal antibodies against C. pneumoniae and C. psittaci, the results might well be suggestive of a novel Chlamydia-like agent. CONCLUSION: Since the novel Chlamydia-like agent was found co-existing with a coronavirus-like agent in the dead cases of SARS, it looks most likely that both the agents play some roles in the disease. At the present time, however, one can hardly determining how did these agents interact each other synergetically, or one follows another, need further study.

[Characterization of Marburg virus morphology].

Ebola virus (EBOV) and Marburg virus (MARV) belong to the family Filoviridae. Filoviruses cause severe filovirus hemorrhagic fever (FHF) in humans, with high case fatality rates, and represent potential agents for bioterrorism and biological weapons. It is necessary to keep surveillance of filoviruses, even though there is no report of their isolation and patients in China so far. To characterize MARV morphology, the Lake Victoria marburgvirus--Leiden was stained negatively and observed under a transmission electron microscope which is one of important detection methods for filoviruses in emergencies and bioterrorism. MARV showed pleomorphism, with filamentous, rod-shaped, cobra-like, spherical, and branch-shaped particles of uniform diameter but different lengths. Pleomorphism of negatively stained MARV is summarized in this article, so as to provide useful information for possible electron microscopic identification of filoviruses in China.

[Morphogenetic study of human adenovirus type 41 in 293TE cells].

To investigate the morphogenetic process of human adenovirus type 41 (HAdV-41), 293TE cells were infected with purified wild-type HAdV-41, and ultrathin sections of infected cells were prepared and observed under a transmission electron microscope. Results showed that HAdV-41 entered host cells mainly through three ways: non-clathrin-coated pit, clathrin-coated pit, and direct penetration of plasma membrane. In addition, cell microvilli might help HAdV-41 enter cells. After entering into cells, HAdV-41 virus particles could be found in vacuoles or lysosomes or be in a free state in cytoplasm. Only free virus particles could be found near nuclear pores (NP), suggesting that the virus needed to escape from lysosomes for effective infection and viral nucleoprotein entered the nucleus through NP. Progeny viruses were as-sembled in the nucleus. Three types of inclusion bodies, which were termed as fibrillous inclusion body, condense inclusion body, and stripped condense inclusion body, were involved in HAdV-41 morphogenesis. In the late phase of viral replication, the membrane integrity of the infected cells was lost and viral particles were released extracellularly. This study reveals the partial process of HAdV-41 morphogenesis and provides more biological information on HAdV-41.