Mitogen-activated protein kinase signalling pathways triggered by the hepatitis C virus envelope protein E2: implications for the prevention of infection

OBJECTIVE

Hepatitis C virus (HCV) is a major pathogenic factor of liver diseases. During HCV infection, interaction of the envelope protein E2 of the virion, with target cells, is a crucial process for viral penetration into the cell and its propagation. We speculate that such interaction may trigger early signalling events required for HCV infection.

MATERIALS AND METHODS

Human liver cell line L-02 was treated with HCV E2. The kinase phosphorylation levels of mitogen-activated protein kinase (MAPK) signalling pathways in the treated cells were analyzed by Western blotting. The proliferation of the E2-treated cells was evaluated by MTT assay.

RESULTS

HCV E2 was shown to be an efficient activator for MAPK pathways. Levels of phosphorylation of upstream kinases Raf-1 and MEK1/2 were seen to be elevated following E2 treatment and similarly, phosphorylation levels of downstream kinases MAPK/ERK and p38 MAPK also increased in response to E2 treatment, and specificity of kinase activation by E2 was confirmed. E2-induced MAPK/ERK activation was inhibited by the MEK1/2 inhibitor U0126 in a concentration-dependent manner. Blockage of relevant cellular receptors reduced activation of Raf-1, MEK1/2, MAPK/ERK and p38 MAPK by E2, indicating efflux of the E2 signal from extracellular to the intracellular spaces. Thus, kinase cascades of MAPK pathways were continuously affected by E2 presence. Moreover, enhancement of cell proliferation by E2 appeared to be associated with the dynamic phosphorylation of MAPK/ERK and p38 MAPK.

CONCLUSION

These results suggest that MAPK signalling pathways triggered by E2 may be a potential target for prevention of HCV infection.

Gene therapy with CX3CL1/Fractalkine induces antitumor immunity to regress effectively mouse hepatocellular carcinoma

CX3CL1/Fractalkine(FK), a chemokine existing in both secreted and membrane anchored form, was reported to induce suppressive activities in tumor models. Here, we demonstrate for the first time the antitumor effects of FK in murine hepatocellular carcinoma (HCC) by constructing a FK eukaryotic expression vector (pIRES-FK) and transferring it into such tumor cells. Tumor rejection experiments were performed by injecting FK gene-modified murine HCC cell line (MM45T.Li) into immunocompetent mice, which significantly inhibited tumorigenicity or growth of MM45T.Li-FK cells. Immunohistochemistry examination and fluorescence-activated cell sorting analyses revealed both CD4+ and CD8+ T cells infiltration within the tumor together with a marked increase of these cells in the peripheral blood. Splenic lymphocyte from mice treated with MM45T.Li-FK were effective in the induction of tumor-specific cytotoxic T cells. We also observed an increased production of IL-2 and IFN-gamma in MM45T.Li-FK tumor tissue. Our results suggest that transfer of the FK gene into tumor cells could elicit a specific antitumor immunity capable of inhibiting tumor growth which lead to increased survival of tumor-bearing hosts. FK should be considered as a chemokine suitable for cancer immunoprevention or gene therapy.

Mutations at F637 in the NMDA receptor NR2A subunit M3 domain influence agonist potency, ion channel gating and alcohol action

BACKGROUND AND PURPOSE

NMDA receptors are important molecular targets of ethanol action in the CNS. Previous studies have identified a site in membrane-associated domain 3 (M3) of the NR1 subunit and two sites in M4 of the NR2A subunit that influence alcohol action; the sites in NR2A M4 also regulate ion channel gating. The purpose of this study was to determine whether mutations at the site in the NR2A subunit corresponding to the NR1 M3 site influence alcohol action and ion channel gating.

EXPERIMENTAL APPROACH

We investigated the effects of mutations at phenylalanine (F) 637 of the NR2A subunit using whole-cell and single-channel patch-clamp electrophysiological recording in transiently-transfected HEK 293 cells.

KEY RESULTS

Mutations at F637 in the NR2A subunit altered peak and steady-state glutamate EC(50) values, maximal steady-state to peak current ratios (I(ss):I(p)), mean open time, and ethanol IC(50) values. Differences in glutamate potency among the mutants were not due to changes in desensitization. Ethanol IC(50) values were significantly correlated with glutamate EC(50) values, but not with maximal I(ss):I(p) or mean open time. Ethanol IC(50) values were linearly and inversely related to molecular volume of the substituent.

CONCLUSIONS AND IMPLICATIONS

These results demonstrate that NR2A(F637) influences NMDA receptor affinity, ion channel gating, and ethanol sensitivity. The changes in NMDA receptor affinity are likely to be the result of altered ion channel gating. In contrast to the cognate site in the NR1 subunit, the action of ethanol does not appear to involve occupation of a critical volume at NR2A(F637).

Inhibition of hepatitis C virus replication and expression by small interfering RNA targeting host cellular genes

Small interfering RNA (siRNA) is a powerful tool for functional genomics and gene therapy. Viral replication and gene expression are strongly inhibited by siRNA treatment of infected mammalian cells. However, the high sequence specificity of siRNAs, combined with prolonged treatment, promote the emergence of siRNA-resistant virus variants, especially among viruses that encode a polymerase lacking proofreading capabilities, indicating that the antiviral properties of specific siRNAs are not as effective as expected. To investigate the silencing effect of siRNAs against selected host cellular proteins that promote replication of hepatitis C virus (HCV), several siRNAs against human VAMP-associated protein (hVAP-A), La antigen and polypyrimidine-tract-binding protein (PTB) were evaluated. The data show that several siRNAs markedly decreased the expression levels of corresponding cellular genes that inhibited HCV replication in Huh-7 cells. These treatments were also shown to have no impact upon cell viability. These findings provide an alternative approach for blocking HCV replication. Hence, combination therapies with siRNAs against both the virus and host genes that support virus replication are likely to be a potent approach in the treatment of chronic hepatitis C.

Visualizing early frog development with motion-sensitive 3-D optical coherence microscopy

A motion-sensitive en-face-scanning 3-D optical coherence microscope (OCM) has been designed and constructed to study critical events in the early development of plants and animals. We describe the OCM instrument and present time-lapse movies of frog gastrulation, an early developmental event in which three distinct tissue layers are established that later give rise to all major organ systems. OCM images constructed with fringe-amplitude data show the mesendoderm migrating up along the blastocoel roof, thus forming the inner two tissue layers. Motion-sigma data, measuring the random motion of scatterers, is used to construct complementary images that indicate the presence of Brownian motion in the yolk cells of the endoderm. This random motion provides additional intrinsic contrast that helps to distinguish different tissue types. Depth penetration at 850 nm is sufficient for studies of the outer ectoderm layer, but is not quite adequate for detailed study of the blastocoel floor, about 500 to 800 mum deep into the embryo. However, we measure the optical attenuation of these embryos to be about 35% less at 1310 nm. 2-D OCT images at 1310 nm are presented that promise sufficient depth penetration to test current models of cell movement near the blastocoel floor during gastrulation.

Therapeutic activity of neutralizing monoclonal antibodies targeting hepatoma-derived growth factor in cancer xenograft models

2517

Background: Hepatoma-derived growth factor (HDGF) is a mitogen for endothelial cells, vessel smooth muscle cells, fibroblasts, as well as some epithelial cells. It is overexpressed in a number of human cancers and its overexpression in tumors strongly correlates with tumor progression, recurrence, and metastasis. We recently showed that down-regulation of HDGF in lung cancer cells reduces tumorigenecity in both in vitro cell and in vivo animal models suggesting HDGF may be of a therapeutic target for cancer. Methods: Recombinant HDGF was used to develop a panel of monoclonal antibodies specifically bind to HDGF. Four antibodies were tested for their therapeutic activity in lung and pancreatic cancer xenograft models. The monoclonal antibodies were administered 250μg/animal (5 mice per group) every 3 days IP when the subcutaneous tumors reached approximately 50 mm3. Results: Two antibodies (C1 and H3) exhibited significant therapeutic activity in A549 lung cancer model whereas H3 also showed a therapeutic effect in MiaPaca-2 pancreatic cancer model. No sign of toxicity in the living animals and histology of major organs were observed in the antibody treated animals. In the A549 model, the mean tumor burden was 960 mm3 for control-IgG treated mice 22 days after tumor inoculation, whereas the mean tumor burdens were 224 mm3 for C1 and 266 mm3 for H3 treated mice (P < 0.05) respectively. In the MiaPaca-2, the mean tumor burden was 994 mm3 for control-IgG treated mice 21 days after tumor inoculation in contrast to 345 mm3 for H3 treated mice (P < 0.05). Consistent with known biologic functions of HDGF, our early morphologic and biomarker analyses suggest that H3 may neutralize tumor cell released HDGF resulting in disruption of tumor stroma and extracellular matrix structures. Conclusions: HDGF is a novel therapeutic target for multiple human cancers and neutralizing monoclonal antibodies targeting HDGF are effective in treating lung and pancreatic cancers in animal models. (Supported by DoD grant DAMD17–01–1-01689–1)

No significant financial relationships to disclose.

G-CSF-mobilized peripheral blood mononuclear cells from diabetic patients augment neovascularization in ischemic limbs but with impaired capability

BACKGROUND

Autologous transplantation of mobilized peripheral blood mononuclear cells (M-PBMNCs) is a novel approach to improve critical limb ischemia (CLI) in diabetes. However, endothelial progenitor cells (EPCs) from diabetes are dysfunctional and impaired in ischemia-induced neovascularization.

OBJECTIVE

This study aimed to confirm the compromised efficiency of diabetic M-PBMNCs in therapeutic neovascularization, and to determine the underlying mechanisms of this impairment.

METHODS

Diabetic M-PBMNCs from 17 diabetic patients or healthy controls, or phosphate-buffered saline (PBS) were injected into the ischemic limbs of streptozotocin-induced diabetic nude mice. The limb blood perfusion, ambulatory score, ischemia damage, capillary/fiber ratio, arteriole density, collateral vessel formation, and pericytes recruitment were evaluated between these three groups. Non-invasive real time image and histopathology were used to detect the in vivo role of transplanted M-PBMNCs. Proliferation and adhesion of EPCs were assayed. In vitro vascular network incorporation and matrigel plug assay were used to test the pro-neovascularization role of M-PBMNCs.

RESULTS

Transplantation of diabetic M-PBMNCs also improved neovascularization, but to a lesser extent from that observed with non-diabetic ones. This was associated with the impairment of diabetic M-PBMNCs capacity to differentiate into EPCs, to incorporate into vessel-like tubules in vitro, to participate in vascular-like structure formation in a subcutaneous matrigel plug, and to stimulate the recruitment of pericytes/smooth muscle cells. In addition, there was impairment in vasculogenesis, which was related to the reduced adhesion ability of EPCs from diabetic M-PBMNCs.

CONCLUSIONS

Diabetes reduced the capacity of M-PBMNCs to augment neovascularization in ischemia.

Actins from plant and animal sources tend not to form heteropolymers in vitro and function differently in plant cells

Pollen and skeletal muscle actins were purified and labeled with fluorescent dyes that have different emission wavelengths. Observation by electron microscopy shows that the fluorescent actins are capable to polymerize into filamentous actin in vitro, bind to myosin S-1 fragments, and have a critical concentration similar to unlabeled actin, indicating that they are functionally active. The globular actins from two sources were mixed and polymerized by the addition of ATP and salts. The copolymerization experiment shows that when excited by light of the appropriate wavelength, both red actin filaments (pollen actin) and green actin filaments (muscle actin) can be visualized under the microscope, but no filaments exhibiting both green and red colors are detected. Furthermore, coprecipitations of labeled pollen actin with unlabeled pollen and skeletal muscle actin were performed. Measurements of fluorescent intensity show that the amount of labeled pollen actin precipitating with pollen actin was much higher than that with skeletal muscle actin, indicating that pollen and muscle actin tend not to form heteropolymers. Injection of labeled pollen actin into living stamen hair cells results in the formation of normal actin filaments in transvacuolar strands and the cortical cytoplasm. In contrast, labeled skeletal muscle actin has detrimental effects on the cellular architecture. The results from coinjection of the actin-disrupting reagent cytochalasin D with pollen actin show that overexpression of pollen actin prolongs the displacement of the nucleus and facilitates the recovery of the nuclear position, actin filament architecture, and transvacuolar strands. However, muscle actin perturbs actin filaments when injected into stamen hair cells. Moreover, nuclear displacement occurs more rapidly when cytochalasin D and muscle actin are coinjected into the cell. It is concluded that actins from plant and animal sources behave differently in vitro and in vivo and that they are functionally not interchangeable.

Corrections to scaling in two-dimensional dynamic XY and fully frustrated XY models

With large-scale Monte Carlo simulations, we investigate the two-dimensional dynamic XY and fully frustrated XY models. Dynamic relaxation starting from a disordered or an ordered state is carefully analyzed. It is confirmed that there is a logarithmic correction to scaling for a disordered start, but a power-law correction for an ordered start. Rather accurate values of the static exponent eta and the dynamic exponent z are estimated.

Construction and analysis of cDNA library of Necator americanus third stage larvae

OBJECTIVE

To obtain the genetic information on Necator americanus and to search for the purpose genes.

METHODS

mRNA was isolated from the third stage larvae of Necator americanus maintained in hamsters. Double strand cDNA was synthesized and ligated to lambda ZAPII vector to construct the cDNA library. Expressed sequence tages (ESTs) were obtained by single pass sequencing of randomly isolated cDNA clones from the established library.

RESULTS

A cDNA library of N. americanus was successfully constructed with high recombinant efficiency. The titer of unamplified library was 1 x 10(7). The insert size was about 750-3,000 bp. Of 11 ESTs obtained from the library, 7 have a significant homology with certain functional genes.

CONCLUSION

A high quality and high representative cDNA library of N. americanus was constructed at the first time and some functional genes were identified from the library by ESTs.

Immunogene therapy of recurrent glioblastoma multiforme with a liposomally encapsulated replication-incompetent Semliki forest virus vector carrying the human interleukin-12 gene--a phase I/II clinical protocol

Glioblastoma multiforme (GBM) is an incurable brain tumor resistant to standard treatment modalities such as surgery, radiation, and chemotherapy. Since recurrent GBM tends to develop predominantly within the infiltrative rim surrounding the primary tumor focus, novel therapy strategies need in addition to focal tumor destruction to target this somewhat diffuse area. This is a phase I/II clinical study in adult patients with recurrent GBM which is aimed at evaluating biological safety, maximum tolerated dose, and antitumor efficacy of a genetically modified replication-disabled Semliki forest virus vector (SFV) carrying the human interleukin 12 (IL-12) gene and encapsulated in cationic liposomes (LSFV-IL12). The vector will be administered in doses of 1 x 10(7)-1 x 10(9) infectious particles by continuous intratumoral infusion, thus exploiting the advantages of convection-enhanced drug delivery in the brain. The present protocol is also designed to investigate systemic and local immune response and to identify factors predicting tumor response to LSFV-IL12 therapy, such as volume of extracellular space of the tumor, volume of contrast enhancing lesion, and immune status of the patients. SFV, an insect alphavirus, infects mitotic and non-mitotic cells and triggers apoptosis in tumor cells within 48-72 h. Preclinical work with the LSFV-IL12 vector in breast and prostate cancer animal models demonstrated its biosafety and some antitumor efficacy. An ongoing phase I clinical study in patients with melanoma and renal cell carcinoma seems also to confirm the biosafety of intravenously administered vectors. This protocol will be the first study of SFV-IL12 therapy of human recurrent GBM.

Oncolytic viruses for treatment of malignant brain tumours

Wild type viruses have been known for decades for their capability to destroy malignant tumour cells upon infection and intracellular replication. Genetic engineering of such viruses was, however, only recently done in an attempt to improve their utility as biological anticancer agents. Wild type or recombinant viruses able to selectively destroy tumour cells while sparing normal tissue are known as oncolytic viruses. Most oncolytic viruses currently investigated in clinical trials are derived from adenovirus (AV) or herpes simplex virus type I (HSVI). More than 300 patients with solid tumours were now treated in clinical trials with oncolytic viruses, and in most cases virus was administered directly into the tumour mass. About 10% of the above patients had recurrent malignant glioma. Total intratumoral doses of up to 2 x 10(12) virus particles were well tolerated, and in general no severe side effects resulted from the clinical use of oncolytic AV and HSVI, either in the brain or in the rest of the body. Encouraging anti-tumoral activity was demonstrated in some types of tumours treated locally with oncolytic viruses, and systemic chemotherapy was found to potentiate the anti-tumour effect of virus mediated oncolysis. In malignant glioma, standard gene therapy approaches employing non-replicating virus vectors failed to demonstrate significant benefit in clinical studies. Therapy with oncolytic viruses seems to hold more promise in early clinical trials than gene therapy with non-replicating virus vectors. However, further major advancements in virus designs, application modalities, and understanding of the interactions of the host's immune system with the virus are clearly needed before oncolytic virus therapy of malignant brain tumours can be introduced to clinical practice.

Construction and identification of a single stranded cDNA clone containing full-length genome of hepatitis G virus

AIM

To construct a single cDNA clone with full-length genome of hepatitis G virus (HGV) could be transcribed and expressed in vitro.

METHODS

The 5 initial HGV cDNA fragments of Iw5, Iwq2, Iwh6, Iw3 and Iw3 used in this study were amplified from serum of a Japanese non A-E hepatitis patient. These fragments overlapped and covered the entire genome from 5'-end to 3'-end of HGV cDNA. Overlap extension PCR and ligation methods were used with 12 primers for the construction of a full-length genomic HGV cDNA clone from the subgenomic fragments.

RESULTS

A single HGV cDNA clone (pHGVqz) was successfully constructed, physical mapping of the generated pHGVqz found identical to what we expected, and the sequence was deposited with the GenBank under the Accession number AF081782. The analysis of the full-length sequence, which was able to be in vitro transcribed and expressed, showed that this single clone contained 9373 nucleotides (encoding 2873 amino acids), and shared high homologies with other compared HGV isolates.

CONCLUSION

A full-length genomic HGV cDNA clone is generated for the first of the kind in this study, it could be expressed and transcripted. This single cDNA clone is expected to be of importance in the investigation on replication and pathogenicity of HGV.

Different protective roles in vitro of alpha- and beta-domains of growth inhibitory factor (GIF) on neuron injuries caused by oxygen free radicals

It was well known that beta-amyloid (Abeta) and tau protein play an important role in pathological procedure of Alzheimer's disease (AD), a senile dementia. The growth inhibitory factor (GIF, also named metallothionein-3, MT-3) had been demonstrated to inhibit the outgrowth of cortex neurons in the medium with extract of the AD patient brain. In our experiments, it was found that the neurons of cortex and the PC12 (pheochromocytoma) cells could be protected from the cytotoxicity of beta-amyloid 25-35 in presence of GIF and its domains. Additionally, GIF can scavenge the hydroxyl radical efficiently in CytC-VitC radical producing system and its alpha-domain shown more effective potentials than its beta-domain. The electron paramagnetic resonance spectra also show that the alpha-domain has more potential ability for eliminating reactive oxygen free radicals than its beta-domain. The results suggest that GIF could act as an efficient scavenger against free radicals in vitro and the alpha-domain in GIF molecule shows more potential in protecting against reactive oxygen species injury than the beta-domain.

[Successful engraftment of HLA-identical sibling cord blood transplantation in an adult with chronic myelogenous leukemia]

OBJECTIVE

To explore the feasibility of cord blood transplantation (CBT) for the treatment of adult hematological malignancies and its long-term hematopoiesis reconstitution and transplantation-related complications.

METHODS

An 18 years old patient (body weight 75 kg) with chronic myelogenous leukemia in first chronic phase received HLA-identical sibling CBT after conditioning with modified busulfan/cyclophosphamide (Bu/CTX) regimen. The transplanted number of nucleated cells was 1.73 x 10(7)/kg of body weight, and that of CD34+ cells 2. 7 x 10(5)/kg. Cyclosporin A and methylprednisolone were given as prophylaxis against graft versus-host disease (GVHD).

RESULTS

The neutrophil count rose to above 0.5 x 10(9)/L on day 18 and platelet count exceeded 50 x 10(9)/L on day 36. Gene analysis showed that bone marrow cells had completely changed to donor's type on day 80. The patient was diagnosed with grade IV acute hepatic GVHD complicated with CMV infection because of severe jaundice on day 90. After the administration of additional immunosuppressive agents, antiviral agents, plasma exchange and in vitro billirubin adsorption, the complications were well controlled. In the follow-up of 24 months', the patient's general condition is good without obvious hepatic dysfunction and Ph chromosome and bcr/abl fusion gene of bone marrow cells were persistently negative.

CONCLUSION

It is the first case reported in China that adult patient with leukemia has been successfully treated by allogeneic CBT, and this indicates that CBT is feasible in the treatment of adult patient with leukemia.

[Role of tumor necrosis factor receptor 1 and Fas antigen in hepatocellular apoptosis of viral hepatitis B patients]

OBJECTIVE

To evaluate the role of tumor necrosis factor receptor 1 (TNFR1) and Fas antigen in hepatocellular apoptosis and necrosis in viral hepatitis B.

METHODS

Seventy paraffin sections from patients with HBV infection were studied. Five cases of normal liver tissues were studied as control. Apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL). TNFR1 and Fas antigen were determined by immunohistochemistry.

RESULTS

Hepatocellular apoptosis and the expression of TNFR 1 and Fas antigen on hepatocytes were not detected in normal liver tissues. In contrast, there was a strong reaction in TUNEL assay and TNFR1 or Fas antigen expressed on hepatocytes in liver tissues infected with HBV. The degree of apoptosis and the expression of TNFR 1 or Fas antigen on hepatocytes had distinct difference in different hepatitis (P<0.005). There was a positive correlation between degrees of the expression of Fas and hepatic apoptosis (P<0.005), but the similar result was not observed in the expression of TNFR 1 and hepatocellular apoptosis. Our observations also showed that TNFR1 was detected in cytoplasm and cell membrane similarly, and Fas antigen was mainly detected in cytoplasm. There was not positive correlation between degrees of the expression of TNFR1 and Fas antigen on hepatocytes. It was showed that 60.9% (28/46) hepatocytes with strong reaction in TUNEL assay expressed both TNFR1 and Fas antigen.

CONCLUSIONS

The degrees of hepatocellular apoptosis and necrosis induced by Fas antigen are stronger than that induced by TNF. The expression of Fas and TNFR 1 on hepatocytes simultaneously may enhance hepatocellular apoptosis in hepatitis B patients.

[The presence and significance of hepatitis B virus DNA and RNA in kidney]

OBJECTIVE

To study the presence and pathogenesis of hepatitis B virus (HBV) DNA and RNA in renal tissues.

METHODS

The presence and distribution of HBV DNA and RNA were investigated in renal biopsy tissues of 27 patients with HBV associated glomerulonephritis by in situ hybridization assay to explore the pathogenesis of HBV in renal tissue.

RESULTS

HBV DNA and RNA, the same as HBV antigens, were present in renal tissues and located in the nuclei and cytoplasm of renal tubular epithelial cells, glomerular mesangium and capillary loops. HBV DNA and RNA were detected in tubular epithelia with the positive rates of 81.5%, 63.0% respectively, which were significantly higher than those in glomeruli (48.1%, 25.9% respectively) (P < 0.05).

CONCLUSION

That HBV exists and replicates too in renal tissues, predominantly in tubular epithelia. The HBV antigens expressed in situ, as well as the antigens from circulation, and lead to renal lesions through immune complex formation or cell immune involvement. Besides glomerular lesions, tubulointerstitial lesions might also determine the progression and prognosis of HBV associated glomerulonephritis.

Amino acid sequence requirements of peptides that inhibit polyglutamine-protein aggregation and cell death

Proteins with expanded polyglutamine domains cause eight inherited neurodegenerative diseases including Huntington's disease. In a previous paper, we identified peptides that inhibit polyglutamine protein aggregation and cell death and now describe the amino acid sequence requirements necessary for these activities. The original 11 amino acid polyglutamine (Q) Binding Peptide 1(QBP1; SNWKWWPGIFD) can be shortened to 8 amino acids (WKWWPGIF) without loss of ability to inhibit polyglutamine aggregation. Three determinants are responsible for inhibition: a tryptophan-rich motif (WKWW), a spacer amino acid and the tripeptide GIF. GIF can be replaced by a repeat of the tryptophan-rich motif, but the spacer remains necessary. We also demonstrate concordance between peptide activity in the in vitro assay and a cellular assay of polyglutamine aggregation and cell death. Polyglutamine binding peptides targeted for intracellular delivery by fusion to TAT retain the ability to inhibit polyglutamine aggregation and cell death in transfected COS 7 cells.

[Amphotericin B for treatment of fungal infections in 40 patients with malignant hematologic diseases]

OBJECTIVE

To observe the therapeutic effect and side effects of amphotericin B for fungal infections in patients with malignant hematologic diseases.

METHODS

40 patients (male 27, female 13; average age 35.5 years) with malignant hematologic diseases were given amphotericin B, 5-50 mg/d per day for 5-85 days (average time 21 days).

RESULTS

The clinical efficacy rate of amphotericin B was 52.5%, and the fungal elimination rate was 56.2%. Among the side effects, rigor and fever were present in 2.5% of the patients. Hypokalaemia was found in 12.5%, hepatotoxicity in 15.0% and nephrotoxicity in 15.0%.

CONCLUSION

As amphotericin B has a broad anti-fungal spectrum and relatively good efficacy, it is still a high-efficiency drug in treatment of systematical fungal infections. However, the use of drug is limited because of its many side effects. Our study indicates that if it is used properly and hepatic and renal function tests are carried out regularly, amphotericin B is a relatively safe and effective drug.

Glasgow Coma Scale, brain electric activity mapping and Glasgow Outcome Scale after hyperbaric oxygen treatment of severe brain injury

OBJECTIVE

To study the effect of hyperbaric oxy gen (HBO) treatment of severe brain injury.

METHODS

Fifty-five patients were divided into a treatment group (n=35 receiving HBO therapy) and a control group (n=20 receiving dehydrating, cortical steroid and antibiotic therapy) to observe the alteration of clinic GCS (Glasgow Coma Scale), brain electric activity mapping (BEAM), prognosis and GOS (Glasgow Outcome Scale) before a nd after hyperbaric oxygen treatment.

RESULTS

In the treatment group GCS, BEAM and GOS were improved obviously after 3 courses of treatment, GCS increased from 5.1 to 14.6 (P<0.01-0.001),the BEAM abnormal rate reduced from 94.3% to 38% (P<0.01-0.001), the GOS good-mild disability rate was 83.7%, and the middle-severe disability rate was 26.3% compared with the control group. There was a statistic significant difference between the two groups (P<0.01-0.001).

CONCLUSIONS

Hyperbaric oxygen treatment could improve obviously GCS, BEAM and GOS of severe brain injury patients, and effectively reduce the mortality and morbidity. It is an effective method to treat severe brain injury.

Glutamine reduces cytokine release, organ damage, and mortality in a rat model of endotoxemia

Clinical trials have demonstrated that glutamine (GLN) supplementation can decrease infectious morbidity and improve survival in a number of settings of critical illness. The mechanism of this protection remains unclear. The objective of this study was to evaluate the effect of GLN on cytokine release, organ injury, and survival from endotoxin-induced septic shock. Endotoxemia was induced in Male Sprague-Dawley rats by intravenous administration of 5 mg/kg Escherichia coli lipopolysaccharide (LPS). Concomitantly, animals were fluid resuscitated with a lactated ringers (LR) solution and given GLN (0.75 g/kg i.v.) or LR alone. Blood samples were obtained at multiple time points post-LPS injury for cytokine analysis. Survival rates were monitored for 72 h. Organ injury was evaluated in a separate set of animals via pathologic exam of tissues harvested 6 h post-LPS injury. A single dose of GLN significantly attenuated the release of TNF-alpha at 2 h (P < 0.005) and IL-1 beta at 4 h (P < 0.0001). This attenuation of cytokine release was associated with a significant decrease in mortality (P < 0.003). Pathologic exam demonstrated significant protection of both lung and small bowel tissue by GLN. Blood gas values 6-h post-LPS injury showed increased PaO2 and bicarbonate concentration in GLN treated animals. These data indicate that GLN can significantly attenuate pro-inflammatory cytokine release, protect against end-organ damage, and decrease mortality from endotoxemia. GLN confers protection even when administered at the onset of endotoxemia, rather then as pre-treatment. Thus, one explanation for the clinical benefits observed from GLN-supplementation may be related to the attenuation of pro-inflammatory cytokines.

[Expression of HBsAg with four eukaryotic expression plasmids in immortalized B-cell line from a chronic hepatitis B patient]

OBJECTIVE

To establish efficient eukaryotic expression system of HBsAg in immortalized B-cell line from a chronic hepatitis B patient, as autologous HLA target cells for detecting HBsAg-specific cytotoxic T-lymphocyte (CTL) response.

METHODS

Four eukaryotic expression plasmids inserted HBsAg gene were transfected into immortalized B-cell line from a chronic hepatitis B patient, then cells were selected with G418 or hygromycin B. HBsAg in culture supernatants and cell lysates were detected with enzyme-linked immunosorbent assay (ELISA).

RESULTS

All eukaryotic expression vectors-transfected immortalized B-cells produced HBsAg, which was readily detectable in culture supernatants and cell lysates.

CONCLUSIONS

Transfection of EBV-immortalized B-cell line with four eukaryotic expression plasmids leads to stable expression of HBsAg, which can be used as autologous HLA target cells for detecting HBsAg-specific CTL response.

[Clinicopathological analysis of 6 cases of diffuse panbronchiolitis]

OBJECTIVE

To study the clinical and pathological characteristics of diffuse panbronchiolitis (DPB).

METHODS

Clinical history of six cases of DPB and their pathological slides were studied and analyzed.

RESULTS

Diffuse panbronchiolitis was characterized by chronic recurrent nasosinusitis and pulmonary infection and respiratory bronchiolitis. Pathologically, all layers of the respiratory bronchiole walls were involved. Prominent chronic inflammation with lymphocytes, plasma cells and histiocytes infiltration was noted in all cases. In the lumens of the bronchioles, PMN or mucus could be identified. The chronic inflammatory cell infiltration also contained numerous foamy macrophages within the walls of the small bronchioles and in the stroma of the lung as well. Among the 6 cases of DPB, two cases were associated with thymoma.

CONCLUSIONS

DPB is a distinct clinicopathological entity. Open lung biopsy or thorocoscopic biopsy is necessary for the correct diagnosis of clinical atypical DPB cases.

The superiority of organically cultivated vegetables to general ones regarding antimutagenic activities

We found organically cultivated (OC) vegetables, using a water-soluble chitosan as a soil improvement agent and leaf surface spray, had much longer shelf life and better taste than that of generally cultivated (GC) vegetables. The purpose of this study is to determine the relative antimutagenic activity between OC and GC vegetables. Eleven OC vegetables were harvested in March and April in 1999 and 2000, and GC ones were supplied as a control from nearby farms on the same date. The former vegetables were planted on the field where no pesticide had been used for the last 3 years. Forward mutation test with Salmonella typhimurium TM677 and 8-azaguanine as a detection agent was used to determine the antimutagenic activity of juices prepared from OC and GC vegetables against authentic mutagens, such as 4-nitroquinoline oxide (4NQO), benzo(a)pyrene (BaP), and 3-amino-1-methyl-5H-pyrido[4,3-b]indole acetate (Trp-P-2). This microbiological test is a convenient method to use for the food samples containing free histidine. Antimutagenic activity was evaluated by the difference of mutagenic activities between mutagenecity of authentic compounds and that observed upon incubation at 37 degrees C for 2h with each vegetable juice. OC Chinese cabbage, carrot, Welsh onion, and Qing-gen-cai suppressed 37-93% of the mutagenic activity of 4NQO, while the GC ones were held down to 11-65%. Against BaP, three species of OC vegetables showed 30-57% antimutagenecity, while GC ones did only 5-30%. Similarly, the OC spinach decreased the activity of Trp-P-2 to 78%, and the GC suppressed it by 49%.

Short-chain fatty acids induce intestinal epithelial heat shock protein 25 expression in rats and IEC 18 cells

BACKGROUND & AIMS

Because short-chain fatty acids (SCFAs) and heat shock proteins (hsps) confer protection to intestinal epithelia cells (IECs), we studied whether SCFAs modulate IEC hsp expression.

METHODS

Hsp 25, hsp72, and hsc73 protein expression in rat intestinal tissues and IEC-18 cells were determined by Western blot and immunohistochemistry. Cell survival under conditions of oxidant stress (monochloramine) was determined using (51)Cr release in hsp25 cDNA anti-sense and sense-transfected cells expressing minimal and increased hsp25, respectively.

RESULTS

Butyrate induces a time- and concentration-dependent increase in hsp25, but not hsp72 or hsc73, protein expression in rat IEC-18 cells but not 3T3 fibroblasts. Other SCFAs, including the poorly metabolized isobutyate, also induced selective expression of hsp25. Butyrate treatment significantly improved the ability of IEC-18 cells to withstand oxidant (monochloramine) injury. This effect could be blocked in cells in which hsp25 induction by butyrate was blocked by stable hsp25 antisense transfection. Additionally, hsp25-transfected overexpressing IEC-18 cells showed increased resistance to monochloramine. In vivo, increasing dietary fiber increased colonic, but not proximal, ileal hsp25 while having no effect on hsp72 or hsc73 expression.

CONCLUSIONS

SCFAs, the predominant anions of colonic fluid derived from bacterial flora metabolism of luminal carbohydrates, protect IECs against oxidant injury, an effect mediated in part by cell-specific hsp25 induction.

Urinary excretion of aquaporin-2 water channel protein in chronic heart failure rats

OBJECTIVE

To study the urinary excretion of aquaporin-2 (AQP2) water channel protein, and the relationship between urine AQP2 concentration and renal AQP2 gene expression in chronic heart failure (CHF) rats.

METHODS

Male Sprague-Dawley rats (200 g-250 g) underwent either a left coronary artery ligation, a model of CHF, or a sham-operation. Nine weeks after surgery, urinary AQP2 concentrations and renal AQP2 protein levels were measured by Western blot.

RESULTS

The urinary concentration of AQP2 water channel protein increased significantly in CHF rats as compared with sham-operated rats (365.6% +/- 102.9% vs 98.5% +/- 47.6%, P < 0.01). There was positive correlation between urinary AQP2 concentration and renal AQP2 protein expression (r = 0.89, P < 0.01).

CONCLUSION

The urinary concentration of AQP2 water channel protein increases significantly in chronic heart failure rats.

[Cytomegalovirus enteritis in recipients of allogeneic peripheral blood stem cell transplantation]

OBJECTIVE

To report 6 cases of cytomeganlovirus (CMV) enteritis in allogeneic bone marrow transplantation (allo-BMT) or peripheral blood stem cell transplantation(PBSCT) recipients and the outcome after treatment.

METHODS

The 6 patients suffered from leukemia and received allo-BMT or allo-PBSCT.

RESULTS

Five of the 6 patients had acute GVHD II-III at 42, 26, 66, 45 and 57 days after transplantation respectively and they recovered after proper treatment. However they soon had severe diarrhea, abdominal pain or/and gastrointestinal bleeding, 5 of the 6 patients received endoscopic examination with biopsy at 50, 57, 80, 65, 35 days after transplantation respectively. They were all diagnosed as having CMV enteritis based on the presence of cytomegalic cells on mucosal biopsy specimens stained with hematoxylin and eosin. Meanwhile the immunoperoxidase stain of histologic specimens for CMV antigen or in situ hybridization by CMV DNA probe was positive. One patient was diagnosed CMV enteritis at 138 days after transplantation based on the clinic and response to therapy. They received antiviral treatment with ganciclovir (DHPG) 500 mg/d for 4 to 21 days, foscarnet 2.4 g q8 h or 4.8 g q12 h for 21 to 90 days, garlic extract 60-120 mg/d, globulin and other supportive measures. All the 6 cases had complete clinical response.

CONCLUSION

CMV enteritis should be diagnosed as soon as possible with histopathologic examination and early proper treatment may lead to good clinical response.

Diffusion coefficient of DNA molecules during free solution electrophoresis

The free-draining properties of DNA normally make it impossible to separate nucleic acids by free-flow electrophoresis. However, little is known, either theoretically or experimentally, about the diffusion coefficient of DNA molecules during free-flow electrophoresis. In fact, many authors simply assume that the Nernst-Einstein relation between the mobility and the diffusion coefficient still holds under such conditions. In this paper, we present an experimental study of the diffusion coefficient of both ssDNA and dsDNA molecules during free-flow electrophoresis. Our results unequivocally show that a simplistic use of Nernst-Einstein's relation fails, and that the electric field actually has no effect on the thermal diffusion process. Finally, we compare the dependence of the diffusion coefficient upon DNA molecular size to results obtained previously by other groups and to Zimm's theory.

[Cloning and phylogenetic analysis of hepatitis-associated TT virus subgenome]

Polymerase chain reaction (PCR) was utilized for the DNA amplification from transfusion transmitted virus (TTV) positive serum samples. Five TTV DNA fragments, overlapped about 90% of the genome, were amplified by long template PCR for the generation of TTV subgenome. Recombinant plasmids were obtained by directly inserting PCR products into pT-Adv vector, and DNA sequence analyses showed they were TTV DNA fragments. By using specific restriction enzymes, five TTV DNA fragments were ligated into a TTV DNA subgenome clone and named as TTV021. TTV021 has been deposited in GenBank database with the accession number AF254410. The results of computer analyses showed that TTV021, 3472 nt long, contains two open reading frames (ORF1, 785 aa; ORF2, 146 aa). Identity alignments between TTV021 and other TTV isolates indicated several high conserved regions existed. Phylogenetic analysis of 356 nt from TTV021 suggested that the isolate has close evolutionary relationship with CHN1 (type 1a), but has far relation with other TTV isolates.

[Construction of a dicistronic expression plasmid vector containing double-valent hepatitis B surface gene]

OBJECTIVE

In order to enhance vaccine response, we constructed a dicistronic expression plasmid containing double HBsAg immunogenes.

METHODS

At first, pcDNA3.1 plasmid vector was digested with NheI and EcoRI to get the coding sequence of the small (S) surface protein of HBV, then cloned into pCI-neo vector and named it pCI-S. By PCR amplification, the product of IRES-S was digested with SalI & BamHI, and cloned into pBluescript IIK+S to generate pBKS-IRES-S vector, then subcloned to the pCI-S plasmid to generate pCI-S-IRES-S, which is a dicistronic plasmid of double value HBsAg genes.

RESULTS

Two plasmids we constructed were digested with related restriction nucleic enzymes. Sequence analysis of HBsAg and IRES-S gene did not reveal any mutation.

CONCLUSIONS

The construction of dicistronic plasmid of divalue HBsAg immunogenes has been well cloned, which is convenient for further research on cell expression and gene immunization in animals.

Design, synthesis, and biological evaluation of a series of simple and novel potential antimalarial compounds

A series of compounds bearing an endocyclic -N-O- moiety with potential antimalarial activity based on simple derivatives of the tropolone purpurogallin was prepared by means of a hetero Diels-Alder reaction using nitrosobenzene as a dienophile. The rationale behind the design of these compounds is presented, together with the synthetic route to derivatives bearing aromatic and aliphatic esters of the C4'-position hydroxyl group of the purpurogallin framework, as well as biological data obtained from in vitro assays against Plasmodium falciparum and Trypanosoma cruzi. Several of the new compounds have activities in the 3-9 microM range, and provide leads for the development of a novel class of antiparasitic drugs with improved biological and pharmacological properties.

Glutamine induces heat shock protein and protects against endotoxin shock in the rat

Enhanced expression of heat shock protein (HSP) has been shown to be protective against laboratory models of septic shock. Induction of HSPs to improve outcome in human disease has not been exploited because laboratory induction agents are themselves toxic and not clinically relevant. In this study, we demonstrate that a single dose of intravenous glutamine causes a rapid and significant increase in HSP25 and HSP72 expression in multiple organs of the unstressed Sprague-Dawley rat. With the utilization of a fluid-resuscitated rat model of endotoxemia, mortality was dramatically reduced by glutamine administration concomitant with the endotoxin injury. Endotoxin-treated animals given glutamine exhibited dramatic increases in tissue HSP expression and marked reduction of end-organ damage. These data suggest glutamine may protect against mortality and attenuate end-organ injury in endotoxemic shock via enhanced HSP expression. Furthermore, glutamine confers protection when administered at the initiation of sepsis, rather than as pretreatment. Thus glutamine appears to be a clinically viable enhancer of HSP expression and may prove beneficial in the therapy of sepsis and sepsis-induced organ injury.

[Clinical and pathologic analysis of Sjögren's syndrome with renal impairment: a report of 84 cases]

OBJECTIVE

To further study the renal damage of Sjögren's syndrome (SS) and its clinical and pathologic characteristics with biopsy and recent technology.

METHODS

84 patients of SS with renal impairment from 1993 to 1999 were analyzed by routine, immunoassay, tubular function and biopsy examination.

RESULTS

55 of the 84 cases presented with renal tubular acidosis (RTA), 5 with diabetes insipidus and 3 with hypokalemic paralysis. Glomerulopathy occurred in 22 cases (nephrotic syndrome 12, glomerulonephritis 10) and mild renal failure (RF) was found in 14. 69.1% of the patients had hypergamma-globulinemia. 64.3% and 44.1% of the patients showed positive anti SS-A and anti SS-B. In 37 renal biopsy specimens 21 showed chronic interstitial nephritis (CIN) with extensive lymphoplasmic cell infiltration and tubular atrophy. 10 of the 37 specimens revealed lupus nephritis (LN, type III and IV) and 5 mesangial proliferative glomerulonephritis (MsPGN). With immunofluorescence tests, no positive findings were seen in most of the specimens, but deposition of IgA, IgM or C(3) was seen in some patients. IgG deposits in the interstitial lymphoplasmic cells were found in 1 patient. 25 patients were treated with prednisone combined with cytoxan (CTX). In 14 patients with renal failure, serum creatinine level returned to normal after treatment.

CONCLUSION

Renal impairment may be the presenting or predominant feature in SS. The major clinical manifestations are RTA and GN. Treatment with prednisone may decrease the infiltration of lymphoplasmic cells in the interstitium, improve the renal function and correct RTA.

[Influence of electroporation on the biological activities of primary rat hepatocytes]

OBJECTIVE

To investigate the influence of electroporation on the biological activities of primary rat hepatocyte and to optimize the electroporation conditions introducing foreign genes into hepatocytes.

METHODS

A single-pulse procedure was performed at low voltage (220-400 V) but high capacitance (500-950 microF). Its influence on hepatocyte activities was detected by Trypan blue exclusion (TBE) and MTT analysis. Besides, ALB, ALT and LDH in the supernatants of hepatocytes were tested by biochemical assay.

RESULTS

Little hepatocyte damage and high survival rate (>90%) was found from 36 hours till 9th day of culture. At 36th hour after electroporation, ALB, ALT and LDH in the supernatants of Group B (220V, 950 microF) and C (400 V, 950 microF) were higher than those of control group. Whereas TBE and MTT analysis failed to indicate the significant difference of cell viability between electroporation groups and control group.

CONCLUSIONS

This electroporation procedure is one of the optimal choices to introduce foreign genes into primary rat hepatocytes.

[Characteristics of granular sludge during start-up of the internal circulation]

The quick start-up of the laboratory scale IC reactor and the characteristics of granular sludge during start-up were studied in this paper. The results showed that the first start-up of IC reactor could be finished in 20 days, while secondary start-up only needed 15 days with COD loading rate of 12-15 kg.(m3.d)-1 and COD removal larger than 85%. During start-up, the characteristics of granular sludge changed greatly: average granular diameter was increased from 0.88 mm to 1.25 mm; average settling velocity was enhanced from 35.4 m.h-1 to 105.17 m.h-1; methanogenic activities of the granular increased up to 4 times as large as the seeded sludge; the main methanobacteria was changed from Methanothrix to Methanococcus and Methanobacterium.

[Humoral immunization and cell-mediated immunization evoked by HBsAg and B7-2 Ag coexpression recombinant adenovirus vector]

OBJECTIVE

To evoke cytotoxic T lymphocytes (CTL) response and seek for a more effective method to treat chronic hepatitis B.

METHODS

The adenovirus vector was constructed with the foreign genes inserted in the early region 1(E1), which directed coexpression of HBV-S and B7-2 antigens by means of an internal ribosomal entry site placed between the two coding sequences. The vector was transfected into 293 cell lines by liposome and the adenovirus expressing the target antigens was obtained by plaque select. The HBsAg and B7-2 antigen expression in in vitro cell culture was measured by ELISA and Western blotting, respectively. The immune responses were measured by ELISA for antibody response and a LDH release assay for CTL activity after immunization with the recombinant adenovirus vector in C57 mice.

RESULTS

HBsAg and B7-2 antigens were highly expressed after infecting the 293 and HepG2 cell lines in vitro. The humoral response to hepatitis B surface antigen was mildly induced and could be enhanced by reinjecting a regular dose of HBsAg antigen vaccine. The cell-mediated immune response was highly induced by the recombinant adenovirus infection. No clear side effect was observed after immunization.

CONCLUSION

This could be a novel strategy for a development of both preventive and therapeutic vaccines against HBV infection. The recombinant adenovirus vector is an effective and safety vector system suitable to the experiments of gene immunization and gene therapy for incurable diseases.

[Recombinant human growth hormone downregulates the apoptosis of HepG(2) cells induced by LPS]

OBJECTIVE

To investigate the effect of LPS on human hepatocytes and study whether recombinant human growth hormone (rhGH) could protect hepatocytes from apoptosis induced by LPS.

METHODS

HepG(2) cells were treated with LPS (20 microg/ml) or LPS and rhGH for 16 hours. The apoptosis of HepG(2) cells was detected by terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) or electron microscopy.

RESULTS

HepG(2) cells treated with LPS exhibited some specific morphological features of typical apoptosis. the percentage of apoptotic cells in HepG(2) cells treated with LPS and hrGH was significantly lower than that treated with LPS (36+/-5.6)% vs (99+/-0.8)%, P<0.001).

CONCLUSIONS

LPS can induce apoptosis of HepG(2) cells, and hrGH can downregulate the apoptotic role of LPS on HepG(2) cells.

Clinical, brain electric earth map, endothelin and transcranial ultrasonic Doppler findings after hyperbaric oxygen treatment for severe brain injury

OBJECTIVE

To analyze the effect and mechanism of hyperbaric oxygen (HBO) treatment for severe brain injury (SBI).

METHODS

Fifty-five patients were divided into a treatment group of 35 patients and a control group of 20 patients. We observed the alterations of clinical, brain electric earth map (BEAM), endothelin (ET) and transcranial ultrasonic Doppler (TCD) findings before and after HBO treatment as well as outcome.

RESULTS

In the treatment group, Glasgow coma scale, BEAM and outcome improved after HBO treatment; compared with that of the control group, it showed a significant difference. After one course of treatment, treatment group ET was reduced from 91.24 +/- 12.18 ng/L to 68.88 +/- 14.37 ng/L (P < 0.01); in control group, ET was reduced from 90.78 +/- 15.71 ng/L to 83.12 +/- 12.22 ng/L, with a statistically significant difference (P < 0.05). TCD records of MCA mean velocity (Vm) was reduced from 64.2 +/- 4.8 cm/s to 51.6 +/- 4.2 cm/s (P < 0.01), and a decrease in MCA systolic velocity (Vs) and pulse index (PI) values was statistically significant (P < 0.01).

CONCLUSION

HBO treatment can improve the clinical, BEAM and outcome of severely brain injured patients, by decreasing acute stage ET and improving the blood velocity of MCA and decreasing cerebral vascular resistance. HBO treatment can reduce cerebral vascular spasms, cerebral ischemia and hypoxia. One of the important mechanisms of HBO treatment for severe brain injury is the lowering of intracranial pressure.

The effect of Bcl-2 adenovirus against murine hepatocyte apoptosis caused by tumor necrosis factor alpha and D-galactosamine

OBJECTIVE

To evaluate the role of Bcl-2 family proteins in hepatic apoptosis caused by TNF-alpha and D-galactosamine.

METHODS

We induced mouse liver injury with TNF-alpha and D-galactosamine, and detected hepatic apoptosis, the expression of Bcl-2, Bax, and Bak proteins on hepatocytes by using TUNEL or immunohistochemistry, respectively. We also observed the expression of Bcl-2 protein on hepatocytes infected with Bcl-2 adenovirus vector and its protection against hepatocyte apoptosis.

RESULTS

Hepatocyte apoptosis was induced in BalB/c mice pretreated with TNF-alpha plus D-galactosamine, accompanying the enhanced expression of Bax, Bak proteins in hepatocytes. Bcl-2 protein was expressed in murine hepatocytes and lasted at least 1 month after injection of Bcl-2 adenovirus vector, which also lowered ALT level from (1372.9+/-251.4)U/L to (796.5+/-78.7)U/L and reduced hepatocyte apoptosis caused by TNF-alpha and D-galactosamine.

CONCLUSIONS

The enhanced expression of Bax, Bak proteins may play a role in hepatocyte apoptosis induced by TNF-alpha and D-galactosamine. D-galactosamine adenovirus vector can partially reduced hepatocyte apoptosis induced by TNF- alpha and D-galactosamine.