Role of humoral immunity against hepatitis B virus core antigen in the pathogenesis of acute liver failure.

Hepatitis B virus (HBV)-associated acute liver failure (ALF) is a dramatic clinical syndrome leading to death or liver transplantation in 80% of cases. Due to the extremely rapid clinical course, the difficulties in obtaining liver specimens, and the lack of an animal model, the pathogenesis of ALF remains largely unknown. Here, we performed a comprehensive genetic and functional characterization of the virus and the host in liver tissue from HBV-associated ALF and compared the results with those of classic acute hepatitis B in chimpanzees. In contrast with acute hepatitis B, HBV strains detected in ALF livers displayed highly mutated HBV core antigen (HBcAg), associated with increased HBcAg expression ex vivo, which was independent of viral replication levels. Combined gene and miRNA expression profiling revealed a dominant B cell disease signature, with extensive intrahepatic production of IgM and IgG in germline configuration exclusively targeting HBcAg with subnanomolar affinities, and complement deposition. Thus, HBV ALF appears to be an anomalous T cell-independent, HBV core-driven B cell disease, which results from the rare and unfortunate encounter between a host with an unusual B cell response and an infecting virus with a highly mutated core antigen.

Neurite Outgrowth Inhibitor B Receptor: A Versatile Receptor with Multiple Functions and Actions.

Members of the reticulon protein family are predominantly distributed within the endoplasmic reticulum. The neurite outgrowth inhibitor (Nogo) has three subtypes, including Nogo-A (200 kDa), Nogo-B (55 kDa), and Nogo-C (25 kDa). Nogo-A and Nogo-C are potent Nogos that are predominantly expressed in the central nervous system. Nogo-B, the splice variant of reticulon-4, is expressed widely in multiple human organ systems, including the liver, lung, kidney, blood vessels, and inflammatory cells. Moreover, the Nogo-B receptor (NgBR) can interact with Nogo-B and can independently affect nervous system regeneration, the chemotaxis of endothelial cells, proliferation, and apoptosis. In recent years, it has been demonstrated that NgBR plays an important role in human pathophysiological processes, including lipid metabolism, angiogenesis, N-glycosylation, cell apoptosis, chemoresistance in human hepatocellular carcinoma, and epithelial-mesenchymal transition. The pathophysiologic effects of NgBR have garnered increased attention, and the detection and enhancement of NgBR expression may be a novel approach to monitor the development and to improve the prognosis of relevant human clinical diseases.

Ketamine Alleviates Depressive-Like Behaviors via Down-Regulating Inflammatory Cytokines Induced by Chronic Restraint Stress in Mice.

The purpose of the present study was to investigate whether ketamine's rapid antidepressant effects were associated with its anti-inflammatory actions and to explore the underlying molecular mechanism. Depressive-like behaviors was induced in mice using chronic restraint stress (CRS) method. Anti-depressive effects of ketamine were evaluated by forced swimming tests (FST) and sucrose preference test (SPT). Subsequently, brain tissue was harvested to investigate inflammatory response in the hippocampus via investigating reactive microglia numbers, serum cytokines levels and the toll-like receptor type 4 (TLR4)/p38 mitogen-activated protein kinase (MAPK) pathway. CRS exposure caused depressive-like behaviors in mice, which was associated with increased pre-inflammatory cytokines (interleukin (IL)-1ß, tumor necrosis factor (TNF)-α and IL-6) levels, reactive microglia numbers and up-regulated regulatory molecules such as TLR4/p38 and P2X7 receptor in hippocampus. Such neurobehavioral and biochemical abnormalities were normalized by ketamine treatment. CRS-induced depression-like behaviours are associated with activation of hippocampal inflammatory response, whereas down-regulation of pro-inflammatory cytokines may contribute to ketamine's antidepressant effects in mice.

Advanced oxidation protein products exacerbates lipid accumulation and atherosclerosis through downregulation of ATP-binding cassette transporter A1 and G1 expression in apolipoprotein E knockout mice.

BACKGROUND: Both clinical data and basic science studies suggest that advanced oxidation protein products (AOPPs) may contribute to the progression of atherosclerosis. The aim of this study was to investigate the effects of AOPPs on ATP-binding cassette transporter (ABC) A1 and ABCG1 expression, lipid accumulation and atherosclerotic lesions in apolipoprotein E knockout (apoE-KO) mice. METHODS AND RESULTS: Male 8-week-old apoE-KO mice were fed a high-fat/high-cholesterol diet. Mice received intraperitoneal injections of AOPPs (5 mg/kg) and/or Janus Kinase (JAK) inhibitor AG-490 (5 mg/kg) once every other day for 8 weeks. As shown in our data, AOPPs increased lipid levels of plasma, and promoted advanced lesions in the aortic regions in apoE-KO mice. The ABCA1, ABCG1 and liver X receptor alpha (LXRα) expression were downregulated in apoE-KO mice treated with AOPPs, whereas the lesions in the aortas were decreased, and the ABCA1, ABCG1 and LXRα expression were upregulated in mice treated with AOPPs plus AG-490, compared to the mice treated with AOPPs only. The ABCA1 and LXRα expressions of aortas, liver and intestine were downregulated in the AOPPs group, while the expressions were upregulated in the AOPPs-plus-AG-490 group when compared to the AOPPs group. The same results can be also observed in peritoneal macrophages. CONCLUSIONS: AOPPs increase accumulation of lipids and exacerbate atherosclerosis through downregulation of ABCA1 and ABCG1 expression, and the JAK-LXRα signaling pathway in apoE-KO mice.

[Effect of PFT-α on apoptosis of spermatogenic cells caused by enorchia].

OBJECTIVE: To determine the molecular mechanism of germ cell apoptosis via investigating the effect of PFT-α on the expression of p53 and bcl-2/bax during experimental cryptorchid cell apoptosis. METHODS: Male Sprague-Dawley rats were assigned into 4 groups: a sham-operated group, a cryptorchid group, a cryptorchid+p53 inhibitor (p53 inhibitor-alpha, PFT-α) group, and a cryptorchid+dissolvent of PFT-α [dimethyl sulphoxide (DMSO)] group. Unilateral cryptorchidism was surgically induced in the rats of the cryptorchid group, PFT-α group, and cryptorchid+dissolvent of PFT-α group. The rats in the PFT-α group and cryptorchid+dissolvent of PFT-α group were intra-peritoneally injected PFT-α and dissolvent of PFT-α, respectively, once a day. The rats were killed on the 7th day after the surgery. The morphology of spermatogenic epithelium at the side of surgery in the rats was observed under light microscope. The apoptosis of spermatogenic cells in the unilateral cryptorchidism was evaluated by TUNEL and flow cytometry (FCM). The protein expression levels of p53, bcl-2, and Bax were detected by Western blot and immunohistochemical assay in turn. RESULTS: Compared with the cryptorchid groups and the cryptorchid+dissolvent of PFT-α group, the seminiferous epithelium of the cryptorchid+p53 inhibitor group appeared orderly, with thicker cell layers and lower apoptosis index, weak protein expression level of p53/Bax and strong protein expression level of bcl-2. CONCLUSION: PFT-α inhibits the germ cell apoptosis caused by the experimental cryptorchidism via increasing the expression of bcl-2 and decreasing the expression of p53 and bax.

Common and complex Notch1 mutations in Chinese oral squamous cell carcinoma.

PURPOSE: To determine Notch1 mutation status in oral squamous cell carcinoma (OSCC) from Chinese population and its potential clinical implications. EXPERIMENTAL DESIGN: Surgically resected OSCC tissues from 51 Chinese patients and 13 head and neck squamous cell carcinoma (HNSCC) cell lines were sequenced for mutations in the entire coding regions of Notch1 and TP53 using a next-generation sequencing platform. Sequences of the genes were also determined in corresponding normal tissues from 46 of the 51 patients. Mutations and their association with clinical parameters were analyzed. RESULTS: Six mutations in Notch1 and 11 mutations in TP53 coding regions were detected in 4 (31%) and 10 (77%) of the 13 HNSCC cell lines, respectively. Forty-two somatic Notch1 mutations, including 7 nonsense mutations and 11 mutations within the domain commonly harboring potential activating mutations in acute lymphoblastic leukemia, were detected in 22 (43%) of the 51 Chinese OSCC tumors. In comparison, 25 somatic TP53 mutations were observed in 21 (41%) of the 51 tumors. Patients whose tumors carried Notch1 mutation had significantly shorter overall and disease-free survivals (P = 0.004 and P = 0.001, respectively, by log-rank test) compared with those whose tumors carried no Notch1 mutation. Multivariate analysis showed that both Notch1 mutation and lymph node metastasis are independent prognostic factors in the patient population (P = 0.001). All 15 patients with both Notch1 mutation and nodal metastasis recurred or metastasized within 2 years after surgery. CONCLUSIONS: Notch1 mutation is common in Chinese OSCC and associates with clinical outcomes. The complexity of the mutation spectrum warrants further investigation of Notch1 in Chinese patients with OSCC.

Involvement of EBV-encoded BART-miRNAs and dysregulated cellular miRNAs in nasopharyngeal carcinoma genesis.

The definite molecular mechanisms underlying the genesis of nasopharyngeal carcinomas (NPCs) remain to be completely elucidated. miRNAs are small non-coding RNAs which are implicated in cell proliferation, apoptosis, and even carcinogenesis through negatively regulating gene expression post-transcriptionally. EBV was the first human virus found to express miRNAs. EBV-encoded BART-miRNAs and dysregulated cellular miRNAs are involved in carcinogenesis of NPC by interfering in the expression of viral and host cell genes related to immune responses and perturbing signal pathways of proliferation, apoptosis, invasion, metastasis and even radio-chemo-therapy sensitivity. Additional studies on the roles of EBV-encoded miRNAs and cellular miRNAs will provide new insights concerning the complicated gene regulated network and shed light on novel strategies for the diagnosis, therapy and prognosis of NPC.

Systematic and quantitative investigation of the mechanism of carbon nanotubes' toxicity toward algae.

Concurrent with the increasing production and application of carbon nanotubes (CNTs) comes an increasing likelihood of CNTs presenting in the aquatic environment, and thereby potentially threatening aquatic organisms via toxic mechanisms that are, at present, poorly understood. This study systematically investigated the toxicity of three multiwalled CNT (MWCNT) samples toward a green alga (Chlorella sp.), focusing on examining and quantifying the contributions of five possible mechanisms to the algal growth inhibition. The results showed that the MWCNTs significantly inhibited the algal growth. The contribution of metal catalyst residues in the MWCNTs to the algal growth inhibition was negligible, as was the contribution from the MWCNTs' adsorption of nutrient elements. The algal toxicity of MWCNTs could mainly be explained by the combined effects of oxidative stress, agglomeration and physical interactions, and shading effects, with the quantitative contributions from these mechanisms depending on the MWCNT size and concentration. At MWCNT concentrations around 96 h IC(50), the oxidative stress accounted for approximately 50% of the algal growth inhibition, whereas the agglomeration and physical interactions, and the shading effects each took approximately 25% of the responsibility.

The influence of dissolved and surface-bound humic acid on the toxicity of TiO2 nanoparticles to Chlorella sp.

NOM is likely to coat TiO2 nanoparticles (nano-TiO2) discharged into the aquatic environment and influence the nanotoxicity to aquatic organisms, which however has not been well investigated. This study explored the influence of nanoparticle surface-bound humic acid (HA, as a model NOM) as well as dissolved HA on the toxicity of nano-TiO2 to Chlorella sp., with a specific focus on adhesion of the nanoparticles to the algae. Results showed that nano-TiO2 and the dissolved HA could inhibit the algal growth with an IC50 of 4.9 and 8.4 mg L⁻¹, respectively, while both dissolved and nanoparticle surface-bound HA could significantly alleviate the algal toxicity of nano-TiO2. IC50 of nano-TiO2 increased to 18 mg L⁻¹ in the presence of 5 mg L⁻¹ of the dissolved HA and to 48 mg L⁻¹ as the result of surface-saturation by HA. Co-precipitation experiment and transmission electron microscopy observation revealed that both dissolved and nanoparticle surface-bound HA prevented the adhesion of nano-TiO2 to the algal cells due to the increased electrosteric repulsion. The generation of intracellular reactive oxygen species (ROS) was significantly limited by the dissolved and nanoparticle surface-bound HA. The prevention of adhesion and inhibition of ROS generation could account for the HA-mitigated nanotoxicity.

STGC3 inhibits xenograft tumor growth of nasopharyngeal carcinoma cells by altering the expression of proteins associated with apoptosis.

STGC3 is a potential tumor suppressor that inhibits the growth of the nasopharyngeal carcinoma cell line CNE2; the expression of this protein is reduced in nasopharyngeal carcinoma compared with normal nasopharyngeal tissue. In this study, we investigated the tumor-suppressing activity of STGC3 in nude mice injected subcutaneously with Tet/pTRE-STGC3/CNE2 cells. STGC3 expression was induced by the intraperitoneal injection of doxycycline (Dox). The volume mean of Tet/pTRE-STGC3/CNE2+Dox xenografts was smaller than that of Tet/pTRE/CNE2+Dox xenografts. In addition, Tet/pTRE-STGC3/CNE2+Dox xenografts showed an increase in the percentage of apoptotic cells, a decrease in Bcl-2 protein expression and an increase in Bax protein expression. A proteomic approach was used to assess the protein expression profile associated with STGC3-mediated apoptosis. Western blotting confirmed the differential up-regulation of prohibitin seen in proteomic analysis. These results indicate that overexpression of STGC3 inhibits xenograft growth in nude mice by enhancing apoptotic cell death through altered expression of apoptosis-related proteins such as Bcl-2, Bax and prohibitin. These data contribute to our understanding of the function of STGC3 in human nasopharyngeal carcinoma and provide new clues for investigating other STGC3-associated tumors.

STGC3 inhibits xenograft tumor growth of nasopharyngeal carcinoma cells by altering the expression of proteins associated with apoptosis

STGC3 is a potential tumor suppressor that inhibits the growth of the nasopharyngeal carcinoma cell line CNE2; the expression of this protein is reduced in nasopharyngeal carcinoma compared with normal nasopharyngeal tissue. In this study, we investigated the tumor-suppressing activity of STGC3 in nude mice injected subcutaneously with Tet/pTRE-STGC3/CNE2 cells. STGC3 expression was induced by the intraperitoneal injection of doxycycline (Dox). The volume mean of Tet/pTRE-STGC3/CNE2+Dox xenografts was smaller than that of Tet/pTRE/CNE2+Dox xenografts. In addition, Tet/pTRE-STGC3/CNE2+Dox xenografts showed an increase in the percentage of apoptotic cells, a decrease in Bcl-2 protein expression and an increase in Bax protein expression. A proteomic approach was used to assess the protein expression profile associated with STGC3-mediated apoptosis. Western blotting confirmed the differential up-regulation of prohibitin seen in proteomic analysis. These results indicate that overexpression of STGC3 inhibits xenograft growth in nude mice by enhancing apoptotic cell death through altered expression of apoptosis-related proteins such as Bcl-2, Bax and prohibitin. These data contribute to our understanding of the function of STGC3 in human nasopharyngeal carcinoma and provide new clues for investigating other STGC3-associated tumors.

[Effect of ciglitazone on THP-1 macrophage CD36 expression and cholesterol influx].

AIM: To investigate the effect of ciglitazone on CD36 expression and cholesterol influx in THP-1 macrophage. METHODS: After exposure of the cultured THP-1 macrophage to ciglitazone for 24 h, [(3)H] labeled Cholesterol influx was determined by FJ-2107P typed liquid scintillator. CD36 mRNA and protein level were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting respectively. RESULTS: PPARγ agonist, ciglitazone, elevated CD36 in both protein and mRNA levels, and increased cholesterol influx in THP-1 macrophage. The levels of cholesterol influx were 20. 3%, 28. 6%, 37. 2%, 44. 3%, 48. 7% respectively. CONCLUSION: Our results indicated that ciglitazone may play an important role in cholesterol influx and modulating CD36 expression in THP-1 macrophage.

Liver X receptor agonist T0901317 reduces atherosclerotic lesions in apoE-/- mice by up-regulating NPC1 expression.

In this study, we studied the effect of liver X receptor (LXR) agonist T0901317 on Niemann-Pick C1 protein (NPC1) expression in apoE-/- mice. Male apoE-/- mice were randomized into 4 groups, baseline group (n=10), control group (n = 14), treatment group (n = 14) and prevention group (n = 14). All of the mice were fed with a high-fat/high-cholesterol (HFHC) diet containing 15% fat and 0.25% cholesterol. The baseline group treated with vehicle was sacrificed after 8 weeks of the diet. The control group and the prevention group were treated with either vehicle or T0901317 daily by oral gavage for 14 weeks. The treatment group was treated with vehicle for 8 weeks, and then was treated with the agonist T0901317 for additional 6 weeks. Gene and protein expression was analyzed by real-time quantitative PCR, immunohistochemistry and Western blotting, respectively. Plasma lipid concentrations were measured by commercially enzymatic methods. We used RNA interference technology to silence NPC1 gene expression in THP-1 macrophage-derived foam cells and then detected the effect of LXR agonist T0901317 on cholesterol efflux. Plasma triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and apoA-I concentrations were markedly increased in T0901317-treated groups. T0901317 treatment reduced the aortic atherosclerotic lesion area by 64.2% in the prevention group and 58.3% in the treatment group. LXR agonist treatment increased NPC1 mRNA expression and protein levels in the small intestine, liver and aorta of apoE-/- mice. Compared with the normal cells, cholesterol efflux of siRNA THP-1 macrophage-derived foam cells was significantly decreased, whereas cholesterol efflux of LXR agonist T0901317-treated THP-1 macrophage-derived foam cells was significantly increased. Our results suggest that LXR agonist T0901317 inhibits atherosclerosis development in apoE-/- mice, which is related to up-regulating NPC1 expression.

Persistence and expression of the adenosine deaminase gene for 12 years and immune reaction to gene transfer components: long-term results of the first clinical gene therapy trial.

The first human gene therapy experiment begun in September 1990 used a retroviral vector containing the human adenosine deaminase (ADA) cDNA to transduce mature peripheral blood lymphocytes from patients with ADA deficiency, an inherited disorder of immunity. Two patients who had been treated with intramuscular injections of pegylated bovine ADA (PEG-ADA) for 2 to 4 years were enrolled in this trial and each received a total of approximately 10(11) cells in 11 or 12 infusions over a period of about 2 years. No adverse events were observed. During and after treatment, the patients continued to receive PEG-ADA, although at a reduced dose. Ten years after the last cell infusion, approximately 20% of the first patient's lymphocytes still carry and express the retroviral gene, indicating that the effects of gene transfer can be remarkably long lasting. On the contrary, the persistence of gene-marked cells is very low (< 0.1%), and no expression of the transgene is detectable in lymphocytes from the second patient who developed persisting antibodies to components of the gene transfer system. Data collected from these original patients have provided novel information about the longevity of T lymphocytes in humans and persistence of gene expression in vivo from vectors driven by the Moloney murine leukemia virus long-terminal repeat (LTR) promoter. This long-term follow-up has also provided unique evidence supporting the safety of retroviral-mediated gene transfer and illustrates clear examples of both the potential and the pitfalls of gene therapy in humans.

[The expression of nitric oxide synthase in testes of male rat].

OBJECTIVES: To determine the expression of nitric oxide synthase (NOS) in testis and to investigate the effects of NO on the reproductive function of testis. METHODS: Testes of adult male Sprague-Dawley rats were fixed in 4% paraformaldehyde. The paraffin sections were made as routine. Immunohistochemical ABC method was used to observe the localization of NOS. RESULTS: Endothelia NOS (eNOS), neuronal NOS (nNOS) and inductive NOS (iNOS) were all expressed in Leydig cells. Only eNOS was expressed in peritubular myoid cells, endothelial and smooth muscle cells of blood vessel, while only nNOS expressed in tunica adventitia of testicular blood vessels. The reactive substance distributes in cytoplasm with negative nuclei. Immunoreactivity for eNOS, nNOS and iNOS in all spermatogenic cells was negative. CONCLUSIONS: Three kinds of NOS were all expressed in testis and the distribution of different NOS had a little difference.