[Expression and clinical significance of Pin1 and Cyclin D1 in cervical cancer cell lines and cervical epithelial tissues]

BACKGROUND & OBJECTIVE

Peptidyl-prolyl cis/trans isomerase Pin1 is prevalently overexpressed in human cancers. Up-regulation of Pin1 elevates the expression of Cyclin D1, and plays an important role in tumorigenesis and tumor progression. This study was to investigate the expression and clinical significance of Pin1 and Cyclin D1 in cervical cancer cell lines and cervical epithelial tissues.

METHODS

The expression of Pin1 and Cyclin D1 in cervical cancer cell lines HeLa, SiHa, C33a and Caski were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Their expression in 88 samples of cervical tissues, including 10 samples of normal cervix, 21 samples of cervical intraepithelial neoplasia (CIN), and 57 samples of invasive cervical cancer, were detected by immunohistochemistry.

RESULTS

The mRNA and protein levels of Pin1 were significantly higher in HeLa, SiHa, C33a, and Caski cells than in normal cervical epithelial tissues (P<0.05). The expression of Pin1 increased progressively along with the disease process from normal cervix to CIN, and to invasive cervical cancer (0%, 47.62%, 64.91%, P<0.05). Pin1 expression had no relation to disease stage (FIGO), pathologic grade, and pelvic lymph node metastasis status (P>0.05). The positive rate of Pin1 was significantly higher in cervical adenocarcinoma than in cervical squamous cell carcinoma (100% vs. 60.0%, P<0.05). In cervical cancer tissues, the overexpression of Pin1 was positively correlated to that of Cyclin D1 (P<0.05).

CONCLUSIONS

Pin1 is overexpressed in HeLa, SiHa, C33a and Caski cell lines as well as in cervical cancer tissues. The overexpression of Pin1 is closely related to Cyclin D1 expression in cervical cancer. The aberrant expression of Pin1 and Cyclin D1 might contribute to tumorigenesis of cervical cancer.

Construction and characterization of a rock-cluster-based EST analysis pipeline

Open access to vast amount of expression sequence tags (ESTs) data in the public databases has provided a powerful platform for gene identification, gene expression studies and comparative/functional genomic studies. To facilitate management of large-scale EST data, high performance cluster and analysis softwares, especially parallel softwares, are fundamentally essential. We reported herein a convenient approach to construct a high performance computating (HPC) cluster based on popular Rocks and a perl-scripted analysis pipeline for EST pre-processing, clustering, assembling and annotation and any other desired analysis modules through parallel computing. We tested the system using different datasets on increasing nodes. Our present results showed that the cluster and pipeline accelerate the EST analysis without artificial interference.

Down-regulation of MT1-MMP expression suppresses tumor cell invasion in metastatic human SW626 ovarian cancer cells

Membrane-type 1 matrix metalloproteinase (MT1-MMP/MMP-14) is a key enzyme involved in degradation of extracellular matrix (ECM) and various surface-associated proteins that control cell growth, differentiation and survival, plays crucial roles in molecular carcinogenesis, tumor cell growth, invasion, and angiogenesis. We tested the inhibitory effect of antisense MT1-MMP on the ability of metastatic human ovarian carcinoma cell line SW626 in proliferation and invasion. RT-PCR was used to amplify MT1-MMP cDNA fragments with two different restriction sites at its 5'-end. Antisense MT1-MMP cloned in eukaryotic expression vector pMMP14as was transfected into SW626 cells. MT1-MMP protein expression, activities of MMP-2 and MMP-9, changes of cell proliferation, and cell invasion ability were detected by Western blot, optimized gelatin zymography, MTT assay and matrigel in vitro invasion assay, respectively. After 48 h transfection, decreased expression of endogenous MT1-MMP protein was detected in pMMP14as-transfected SW626 cells and showed significantly lower proliferation level when compared with control cells. The activation of proMMP-2 was inhibited markedly, and the mean percentage of invasive cells was 63.30+/-5.80% in pMMP14as-transfected cells, which was less than that (97.60+/-7.50%) in control cells (P<0.05). Both cell proliferation and invasion in SW626 cells were inhibited effectively by antisense MT1-MMP transfection, suggesting that MT1-MMP may be a proper target molecule for anti-invasion therapy for human ovarian cancers.

HFIP-induced structures and assemblies of the peptides from the transmembrane domain 4 of membrane protein Nramp1

Membrane protein Nramp1 (natural resistance-associated macrophage protein 1) is a pH-dependent divalent metal cation transporter that regulates macrophage activation in infectious and autoimmune diseases. A naturally occurring glycine to aspartic acid substitution at position 169 (G169D) within the transmembrane domain 4 (TM4) of Nramp1 makes mice susceptible to Leishmania donovani, Salmonella typhimurium, and Mycobacterium bovis. Here we present a structural and self-assembling study on two synthetic 24-residue peptides, corresponding to TM4 of mouse Nramp1 and its G169D mutant, respectively, in 1,1,1,3,3,3-hexafluoroisopropanol-d(2) (HFIP-d(2)) aqueous solution by nuclear magnetic resonance (NMR) spectroscopy. The results show that amphipathic alpha-helical structures are formed from residue Ile173 to Tyr187 for the wild-type peptide and from Trp168 to Tyr187 for the G169D mutant, respectively. The segment of the N-terminus from Leu167 to Leu172 is poorly structured for the wild-type peptide, whereas it is well defined for the G169D mutant. Both peptides aggregate to form a tetramer and the monomeric peptides in peptide bundles are structurally and orientationally similar. The intermolecular interactions in assemblies could be stronger in the C-terminal regions related to residues Phe180-Leu184 than those in the central helical segments for both peptides. The G169D mutation may change the size of the opening on the termini of assembly.

Formation mechanism of nonspherical gold nanoparticles during seeding growth: Roles of anion adsorption and reduction rate

A small section of nonspherical particles can be observed in the further growth of spherical gold colloids exposed to a mixture of NH2OH and HAuCl4. The concentration ratio of [NH2OH]:[HAuCl4] is critical for the formation of nonspherical particles as higher ratios produce lower yields and smaller of such particles. These concentrations also affect the reaction kinetics; the reaction rate increases with [NH2OH], while independent of [HAuCl4], which we believe is due to the specific adsorption of AuCl4- onto gold surface. These nonspherical particles come from the preferential growth of {111} facets as indicated by their TEM images and electron diffraction patterns. We propose this preferential growth is ascribed to the preferential adsorption of AuCl4- on {111} facets, and some competition which determines the yield of nonspherical particles exists between the AuCl4- adsorption and the AuCl4- reduction, faster reduction counteracting the effect of this preferential adsorption and thus suppressing nonspherical particle. This result probably provides some guidance to develop a shape-controlled synthesis of gold particles without any additives.

Observation of organochlorine pesticides in the air of the Mt. Everest region

High mountains have been suggested to play an important role in the global transport of persistent organic pollutants, yet observation of these pollutants in high mountains is very limited. In the summer of 2002, air samples were collected at Dingri at a height of 4400 m above sea level (m a.s.l.) and at Rongbuk Valley (4976 m a.s.l.) in the Mt. Everest region and analyzed using large volume injection gas chromatography tandem mass spectrometry. The mean concentrations of organochlorine pesticides (OCPs) in the samples were 19.2, 11.2, 7.7, 8.9, 10.4, 27.6, 5.1, 5.1, and 3.7 pg m(-3) for alpha-HCH, beta-HCH, gamma-HCH, HCB, heptachlor, alpha-endosulfan, p,p'-DDE, o,p'-DDT, and p,p'-DDT, respectively. Backward trajectories were used to assess the association between source regions, transport paths, and observed OCP concentrations. During the sampling period, the o,p'-DDT/p,p'-DDT concentration ratios were observed to be between 1.23 and 1.41, much higher than that of technical DDT, indicating the existence of a DDT source other than technical DDTs in the source regions.

Simple, one-step synthesis of gold nanowires in aqueous solution

A simple procedure to synthesize gold nanowires based on the reduction of hydrogen tetrachloroaurate by 2-mercaptosuccinic acid in aqueous solution is presented. This procedure requires no additional capping or reduction agent and produces wires with an apparent curly morphology several micrometers in length with diameters as thin as 15 nm. Some of the wires produced end in a ribbonlike structure, finally terminated by a flat triangular prism. Investigations by scanning electron microscopy, transmission electron microscopy (bright and dark field), scanning transmission electron microscopy, and atomic force microscopy as well as conductivity measurements indicate fully connected, polycrystalline gold objects.

Engineering of Bacillus subtilis for enhanced total synthesis of folic acid

We investigated whether the yield of the B vitamin folic acid could be elevated in Bacillus subtilis. Strategies for increasing the folic acid yield were investigated by employing computer-aided flux analysis and mutation. Controlling the activity of the enzyme pyruvate kinase by placing it under inducible control was one strategy devised to elevate yield while insuring that a rapid growth rate results. Other single mutation strategies included amplifying the expression of the genes in the folate operon and overexpressing the Escherichia coli aroH gene, which encodes 2-dehydro-3-deoxyphosphoheptonate aldolase. The latter could conceivably elevate the abundance of the folic acid precursor, para-aminobenzoic acid. Strains that combined two or more mutations were also constructed. Overall, a strain possessing inducible pyruvate kinase, overexpressed aroH, and increased transcription and translation of genes from the folic operon exhibited the best yield. The yield was eightfold higher than that displayed by the parent B. subtilis 168 strain.

[Automated anesthesia record system]

Based on Client/Server architecture, a software of automated anesthesia record system running under Windows operation system and networks has been developed and programmed with Microsoft Visual C++ 6.0, Visual Basic 6.0 and SQL Server. The system can deal with patient's information throughout the anesthesia. It can collect and integrate the data from several kinds of medical equipment such as monitor, infusion pump and anesthesia machine automatically and real-time. After that, the system presents the anesthesia sheets automatically. The record system makes the anesthesia record more accurate and integral and can raise the anesthesiologist's working efficiency.

Role of hTERT in apoptosis of cervical cancer induced by histone deacetylase inhibitor

Human telomerase reverse transcriptase (hTERT) is the catalytic subunit of telomerase holoenzyme as well as the rate-limiting component of the telomerase enzyme complex. However, the role of the hTERT in apoptosis induced by histone deacetylase inhibitor has only been marginally addressed. For the first time, our study demonstrated that trichostatin A (TSA) briefly activated the proliferation of cervical cancer cell lines, HeLa and SiHa, within 12 h, but then inhibited cell growth after that time point. In response to TSA, hTERT expression, telomerase activity, and telomere length also underwent similar changes during the same time frame. Furthermore, the data in our study showed that cells transfected with dominant negative hTERT were more likely to undergo apoptosis induced by TSA than cells transfected with wild-type hTERT. The cyclin/cdk inhibitor p21waf1 was down-regulated by hTERT without changing the expression of p53. Results from this study suggest that the hTERT might be a primary target of TSA and the anti-apoptosis effect of hTERT might be carried out through a p21waf1-dependent and p53-independent pathway.

[Clinical effects of combination chemotherapy with irinotecan hydrochloride and cisplatin on cervical cancer: study of 46 patients]

OBJECTIVE

To evaluate the efficacy and toxicity of the combination chemotherapy of irinotecan hydrochloride plus cisplatin on cervical cancer.

METHODS

Forty-six patients with cervical cancer, 43 with squamous cell carcinoma, 2 adenocarcinoma, and 1 small cell carcinoma, 41 being treated initially and 5 being recurrent cases of which 2 had undergone radiotherapy plus chemotherapy, 2 radical hysterectomy plus pelvic radiotherapy after operation, and 1 radical hysterectomy plus chemotherapy, aged 38 (22-61), were treated with irinotecan hydrochloride, 60 mg/m(2) in 250 ml normal saline administered on days 1, 8, and 15 by intravenous infusion over 60 min, plus cisplatin, 60 mg/m(2) in 500 ml 5% glucose given on day 1. This regimen was repeated every 28 days. Effectiveness evaluation was conducted after 1-2 courses for the initially treated patients and after 2-6 courses for the recurrent patients.

RESULTS

Totally 79 courses of treatment were given to the 41 patients. After 1-2 courses 4 (9.8%) of the 41 stage Ib2-IIIb initially treated patients achieved complete remission, 30 (73.2%) achieved partial remission, and 7 (17.1%) remained at stationary phase with a overall effective rate of 82.9%. Of the 29 IIb and IIIb stage advanced patients who failed to receive operation originally 20 patients (69%) succeeded to be treated by radical hysterectomy after 1 to 2 courses when the tumorless space between the uterine and the pelvic wall > or = 3 cm with an operatibility rate of 69%. Of the 5 recurrent patients 1 case achieved complete remission, 2 partial remission, and 2 remained stable; none progression of disease was observed after 4-6 courses. The main toxic response and side effect included myelosuppression and diarrhea.

CONCLUSION

Effective neoadjuvant chemotherapy on cervical cancer, combination therapy of irinotecan hydrochloride and cisplatin win opportunity for treatment and improves their life quality with tolerable side effects.

[Expression of human telomerase reverse transcriptase in cervix cancer and its significance]

OBJECTIVE

To investigate the expression of human telomerase reverse transcriptase (hTERT) mRNA and protein in cervix cancer, cervical intraepithelial neoplasia (CIN) and normal cervix.

METHODS

Expression of hTERT mRNA and the other two subunits of telomerase, human telomerase RNA component (hTR), human telomerase-associated protein (hTP1) was determined by RT-PCR in 3 cervix cancer cell lines, 2 diploid cell lines, 38 cases of cervix cancer, 16 cases of CIN and 20 cases of normal cervix. Telomerase activity was also examined by telomeric repeat amplification protocol enzyme-linked immunosorbent assay (TRAP-ELISA). Expression of hTERT protein was detected in all the cell lines and 101 cases of paraffinized cervix tissue sections.

RESULTS

hTERT mRNA expression was detected in all of the three cervix cancer cell lines, 81.6% of cervix cancer, 37.5% of CIN, 5.0% of normal cervix, while in neither of the two diploid cell lines. The other two subunits of telomerase were prevalently expressed in all of the cell lines and most cervix tissues. There was a strong correlation between hTERT mRNA expression and telomerase activity. Immunostaining also revealed that hTERT protein was expressed in all three cervix cancer cell lines, 65.5% of cervix cancer, 28.0% of CIN and 4.8% of normal cervix.

CONCLUSION

Up-regulation of hTERT may play an important role in the development of CIN and cervix cancer, hTERT could be used as an early diagnostic biomarker for cervix cancer.

Surface-Enhanced Raman Scattering ofp-Aminothiophenol on a Au(core)/Cu(shell) Nanoparticle Assembly

Surface-enhanced Raman scattering (SERS) of p-aminothiophenol (PATP) molecules adsorbed onto assemblies of Au(core)/Cu(shell) nanoparticles is reported. We compare it with the SERS spectrum of PATP adsorbed onto gold nanoparticles: both the absolute and relative scattered intensities of various bands in the two spectra are very different. The difference in relative intensity can be ascribed to chemical effects; the chemical enhancement ratio of the two substrates is approximately 3-5. A theoretical analysis based on a charge-transfer model is carried out, which yields a consistent result and shows that the difference in chemical enhancement is mainly due to the state densities and Fermi levels of the substrates. The difference in absolute intensity originates from electromagnetic (EM) enhancement. EM enhancement of Au(core)/Cu(shell) nanoparticles is unlike that of single-component gold or copper SERS-active substrates. The core/shell particle size for optimal enhancement is about 20 nm in the case of a 632.8 nm incident laser (the size ratio of the core and shell layers is about 0.6).

Tissue factor enhances protease-activated receptor-2-mediated factor VIIa cell proliferative properties

In addition to its hemostatic functions, factor (F)VIIa exhibits cell proliferative properties as seen in angiogenesis and tumor growth. A role for tissue factor (TF) and protease-activated receptors (PAR)-1 and -2 in cell proliferation remain to be clarified. We tested the hypothesis that FVIIa induces cell proliferation by a mechanism involving TF and PAR-2. Human recombinant FVIIa induced cell proliferation of human BOSC23 cells transfected with plasmid containing human TF DNA sequence. Because DNA primase 1 (PRIM1) plays an essential role in cell proliferation, we used the cloned PRIM1 promoter upstream of the reporter gene chloramphenicol acetyl transferase (CAT) to elucidate the mode of action of FVIIa. FVIIa evoked a dose-dependent increase in cell proliferation and PRIM1 induction, which were markedly potentiated (4-5-fold) by the presence of TF and abrogated by TF antisense oligonucleotide. PRIM1 induction by FVIIa was also abolished by PAR-2 but not by PAR-1 antisense. In contrast, thrombin induced a small increase in CAT activity which was unaffected by TF, but was prevented only by PAR-1 antisense as well as the thrombin inhibitor hirudin. Proliferative properties of FVIIa were associated with a TF-dependent increase in intracellular calcium and were mediated by a concordant phosphorylation of p44/42 MAP kinase. In conclusion, data reveal that FVIIa induces PRIM1 and ensuing cellular proliferation via a TF- and of the PARs entirely PAR-2-dependent pathway, in distinction to that of thrombin which is PAR-1-dependent and TF-independent. We speculate that FVIIa-TF-PAR-2 inhibitors may be effective in suppressing cell proliferation.

p44/42 MAP kinase-dependent regulation of catalase by autocrine human growth hormone protects human mammary carcinoma cells from oxidative stress-induced apoptosis

Previous microarray expression analyses have indicated autocrine human growth hormone (hGH) regulation of genes involved in the oxidative stress response. Expression analysis of antioxidant enzymes revealed that autocrine hGH increased both the mRNA and protein levels of catalase, superoxide dismutase 1 (SOD1), glutathione peroxidase and glutamylcysteine synthetase but not that of SOD2. As a consequence, autocrine hGH increased the antioxidant capacity of mammary carcinoma cells and protected against oxidative stress-induced apoptosis. Catalase activity was increased by autocrine production of hGH in mammary carcinoma cells and a catalase inhibitor abrogated protection from oxidative stress afforded by autocrine hGH. Autocrine hGH transcriptionally regulated catalase gene expression in a p44/42 MAP kinase-dependent manner and inhibition of MEK concordantly abrogated the protective effect of autocrine hGH against oxidative stress-induced apoptosis. Given that increased cellular oxidative stress is a key effector mechanism of specific chemotherapeutic agents, we propose that antagonism of autocrine hGH will improve the efficacy of chemotherapeutic regimes utilized for human mammary carcinoma.

Reproducible Patterning of Single Au Nanoparticles on Silicon Substrates by Scanning Probe Oxidation and Self-Assembly

This paper describes a rational approach for reproducibly patterning single Au nanoparticles, 15-20-nm diameter, on silicon wafer substrates. The approach uses scanning probe oxidation (SPO) to pattern silicon oxide nanodomain arrays on silicon substrates modified with octadecyltrimethoxysilane (OTS). It was usually found using aminopropyltrimethoxysilane (APS) that Au nanoparticles only assembled at the domain boundaries probably because of asymmetrically distributed hydroxyl groups. To generate uniformly distributed hydroxyl groups on oxide domains, we employed a two-step treatment to etch and oxidize the substrate. With this treatment, oxide domains consistently attached Au nanoparticles to maximum capacity. Single Au nanoparticles were readily patterned by fabricating oxide nanodomains with a diameter below 30 nm. We also investigated the deposition of APS on OTS monolayers, which resulted in the assembly of Au nanoparticles outside of the oxide domains, and proposed two alternative methods to inhibit it.

Oncogenic Transformation of Human Mammary Epithelial Cells by Autocrine Human Growth Hormone

The human growth hormone (hGH) gene is expressed in the normal human mammary epithelial cell and its expression increases concomitant with the acquisition of proliferative lesions. Herein we demonstrate that autocrine production of hGH in human mammary carcinoma cells dramatically enhances anchorage-independent growth in a Janus kinase 2–dependent manner. Forced expression of the hGH gene in immortalized human mammary epithelial cells increased proliferation, decreased apoptosis, altered the cellular morphology and resulted in oncogenic transformation. Autocrine hGH was therefore sufficient to support anchorage-independent growth of immortalized human mammary epithelial cells and tumor formation in vivo. Moreover, autocrine hGH disrupted normal mammary acinar architecture with luminal filling and deregulated proliferation in three-dimensional epithelial cell culture. Autocrine hGH utilized homeobox A1 to govern the transcriptional program required for autocrine hGH–stimulated oncogenic transformation of human mammary epithelial cells, including transcriptional up-regulation of c-Myc, cyclin D1, and Bcl-2. Forced expression of a single orthotopically expressed wild-type gene is therefore sufficient for oncogenic transformation of the immortalized human mammary epithelial cell.

Oncogenic transformation of human mammary epithelial cells by autocrine human growth hormone

The human growth hormone (hGH) gene is expressed in the normal human mammary epithelial cell and its expression increases concomitant with the acquisition of proliferative lesions. Herein we demonstrate that autocrine production of hGH in human mammary carcinoma cells dramatically enhances anchorage-independent growth in a Janus kinase 2-dependent manner. Forced expression of the hGH gene in immortalized human mammary epithelial cells increased proliferation, decreased apoptosis, altered the cellular morphology and resulted in oncogenic transformation. Autocrine hGH was therefore sufficient to support anchorage-independent growth of immortalized human mammary epithelial cells and tumor formation in vivo. Moreover, autocrine hGH disrupted normal mammary acinar architecture with luminal filling and deregulated proliferation in three-dimensional epithelial cell culture. Autocrine hGH utilized homeobox A1 to govern the transcriptional program required for autocrine hGH-stimulated oncogenic transformation of human mammary epithelial cells, including transcriptional up-regulation of c-Myc, cyclin D1, and Bcl-2. Forced expression of a single orthotopically expressed wild-type gene is therefore sufficient for oncogenic transformation of the immortalized human mammary epithelial cell.

BOD: a customizable bioinformatics on demand system accommodating multiple steps and parallel tasks

The integration of bioinformatics resources worldwide is one of the major concerns of the biological community. We herein established the BOD (Bioinformatics on demand) system to use Grid computing technology to set up a virtual workbench via a web-based platform, to assist researchers performing customized comprehensive bioinformatics work. Users will be able to submit entire search queries and computation requests, e.g. from DNA assembly to gene prediction and finally protein folding, from their own office using the BOD end-user web interface. The BOD web portal parses the user's job requests into steps, each of which may contain multiple tasks in parallel. The BOD task scheduler takes an entire task, or splits it into multiple subtasks, and dispatches the task or subtasks proportionally to computation node(s) associated with the BOD portal server. A node may further split and distribute an assigned task to its sub-nodes using a similar strategy. In the end, the BOD portal server receives and collates all results and returns them to the user. BOD uses a pipeline model to describe the user's submitted data and stores the job requests/status/results in a relational database. In addition, an XML criterion is established to capture task computation program details.

Surfactant-Directed Polypyrrole/CNT Nanocables: Synthesis, Characterization, and Enhanced Electrical Properties

We describe here a new approach to the synthesis of size-controllable polypyrrole/carbon nanotube (CNT) nanocables by in situ chemical oxidative polymerization directed by the cationic surfactant cetyltrimethylammonium bromide (CTAB) or the nonionic surfactant polyethylene glycol mono-p-nonylphenyl ether (Opi-10). When carbon nanotubes are dispersed in a solution containing a certain concentration of CTAB or Opi-10, the surfactant molecules are adsorbed and arranged regularly on the CNT surfaces. On addition of pyrrole, some of the monomer is adsorbed at the surface of CNTs and/or wedged between the arranged CTAB or Opi-10 molecules. When ammonium persulfate (APS) is added, pyrrole is polymerized in situ at the surfaces of the CNTs (core layer) and ultimately forms the outer shell of the nanocables. Such polypyrrole/CNT nanocables show enhanced electrical properties; a negative temperature coefficient of resistance at 77-300 K and a negative magnetoresistance at 10-200 K were observed.

Changes of interleukin-1 beta, tumor necrosis factor alpha and interleukin-6 in brain and plasma after brain injury in rats

OBJECTIVE

To study the changes of interleukin-1 beta (IL-1beta), tumor necrosis factor alpha (TNFalpha) and interleukin-6 (IL-6) levels in brain and plasma after brain injury and to assess the relationship between the cytokine levels and injury severity in rats.

METHODS

A total of 51 male Wistar rats, weighing 280-340 g, were anesthetized with chloral hydrate (400 mg/kg body weight) through intraperitoneal injection and fixed on a stereotaxic instrument. Severe brain injury was created in 16 rats (severe injury group) and moderate brain injury in 18 rats (moderate injury group) by a fluid percussion model, and cytokine levels of IL-1beta, TNFalpha and IL-6 were measured with biological assay. And sham operation was made on the other 17 rats (control group).

RESULTS

In the control group, the levels of IL-1beta, TNFalpha and IL-6 were hardly detected in the cortex of the rats, but in the ipsilateral cortex of the rats in both injury groups, they increased obviously at 8 hours after injury. The increasing degree of these cytokines had no significant difference between the two injury groups. The levels of IL-6 in the plasma of all the rats increased slightly, whereas the levels of IL-1beta and TNFalpha were undetectable.

CONCLUSIONS

The increase of IL-1beta, TNFalpha and IL-6 levels is closely related to brain injury. The increased cytokine levels in the central nervous system are not parallel to those in the peripheral blood. It suggests that inflammatory cytokines play important roles in the secondary neural damage after brain injury.

Efficient and long-term intracardiac gene transfer in delta-sarcoglycan-deficiency hamster by adeno-associated virus-2 vectors

Intracardiac gene transfer and gene therapy have been investigated with different vector systems. Here we used adeno-associated virus (AAV) vectors to deliver either a reporter gene or a therapeutic gene into the heart of golden Syrian hamsters. The method of gene delivery was direct infusion of the AAV2 vectors into the coronary artery ex vivo in a heterotopically transplanted heart. When an AAV2 vector carrying the Lac-Z gene driven by CMV promoter was delivered into the heart of healthy hamsters, effective gene transfer was achieved in up to 90% of the cardiomyocytes. Lac-Z gene expression persisted for more than 1 year without immune rejection or promoter shutoff. Furthermore, when an AAV2 vector carrying human delta-sarcoglycan gene was similarly delivered into the heart of Bio14.6 Syrian hamster, a congestive heart failure and limb girdle muscular dystrophy animal model, widespread therapeutic gene transfer was achieved in a majority of the cardiomyocytes. Efficient expression of the human delta-sarcoglycan gene in the dystrophic hamster hearts restored the entire sarcoglycan complex that was missing due to the primary deficiency of delta-sarcoglycan. Transgene expression persisted for 4 months (the duration of the study) without immune rejection or promoter shutoff. These results indicate that AAV is a promising vector system for cardiac gene therapy.

Src-CrkII-C3G-dependent activation of Rap1 switches growth hormone-stimulated p44/42 MAP kinase and JNK/SAPK activities

We demonstrate here that growth hormone (GH) stimulates the activation of Rap1 and Rap2 in NIH-3T3 cells. Full activation of Rap1 and Rap2 by GH necessitated the combined activity of both JAK2 and c-Src kinases, although c-Src was predominantly required. GH-stimulated Rap1 and Rap2 activity was also demonstrated to be CrkII-C3G-dependent. GH stimulated the tyrosine phosphorylation of C3G, which again required the combined activity of JAK2 and c-Src. C3G tyrosine residue 504 was required for GH-stimulated Rap activation. Activated Rap1 inhibited GH-stimulated activation of RalA and subsequent GH-stimulated p44/42 MAP kinase activity and Elk-1-mediated transcription. In addition, we demonstrated that C3G-Rap1 mediated CrkII enhancement of GH-stimulated JNK/SAPK activity. We have therefore identified a linear JAK2-independent pathway switching GH-stimulated p44/42 MAP kinase and JNK/SAPK activities.

Phosphorylation of protein kinase C sites in NBD1 and the R domain control CFTR channel activation by PKA

Activation of the cystic fibrosis transmembrane conductance regulator (CFTR) channel by protein kinase A (PKA) is enhanced by protein kinase C (PKC). However, the mechanism of modulation is not known and it remains uncertain whether PKC acts directly on CFTR or through phosphorylation of an ancillary protein. Using excised patches that had been pre-treated with phosphatases, we found that PKC exposure results in much larger PKA-activated currents and shifts the PKA concentration dependence. To examine if these effects are mediated by direct PKC phosphorylation of CFTR, a mutant was constructed in which serines or threonines at nine PKC consensus sequences on CFTR were replaced by alanines (i.e. the '9CA' mutant T582A/T604A/S641A/T682A/S686A/S707A/S790A/T791A/S809A). In excised patches, 9CA channels had greatly reduced responses to PKA (i.e. 5-10 % that of wild-type), which were not enhanced by PKC pre-treatment, although the mutant channels were still functional according to iodide efflux assays. Stimulation of iodide efflux by chlorophenylthio-cAMP (cpt-cAMP) was delayed in cells expressing 9CA channels, and a similar delay was observed when cells expressing wild-type CFTR were treated with the PKC inhibitor chelerythrine. This suggests that weak activation by PKA in excised patches and slow stimulation of iodide efflux from intact cells are specifically due to the loss of PKC phosphorylation. Finally, PKC caused a slight activation of wild-type channels when added to excised patches after phosphatase pre-treatment but had no effect on the mutant. We conclude that direct phosphorylation of CFTR at one or more of the nine sites mutated in 9CA is required for both the partial activation by PKC and for its modulation of CFTR responses to PKA.

A metabolic network analysis & NMR experiment design tool with user interface-driven model construction for depth-first search analysis

A Windows program for metabolic engineering analysis and experimental design has been developed. A graphical user interface enables the pictorial, "on-screen" construction of a metabolic network. Once a model is composed, balance equations are automatically generated. Model construction, modification and information exchange between different users is thus considerably simplified. For a given model, the program can then be used to predict all the extreme point flux distributions that optimize an objective function while satisfying balances and constraints by using a depth-first search strategy. One can also find the minimum reaction set that satisfies different conditions. Based on the identified flux distributions or linear combinations, the user can simulate the NMR and GC/MS spectra of selected signal molecules. Alternately, spectra vectorization allows for the automated optimization of labeling experiments that are intended to distinguish between different, yet plausible flux extreme point distributions. The example provided entails predicting the flux distributions associated with deleting pyruvate kinase and designing 13C NMR experiments that can maximally discriminate between the flux distributions.