Long-term follow-up study on peer-led school-based HIV/AIDS prevention among youths in Shanghai

SUMMARY

The HIV/AIDS epidemic is a major problem around the world and an increasing percentage of new HIV cases is reported to be by sexual transmission. Many studies have been carried out in the field of peer education on HIV/AIDS among young people, however, few studies focused on the long-term effect of this education. To evaluate both the short- and long-term effects of the peer education programme, we conducted a follow-up study to evaluate the related knowledge, attitudes and behaviour intention to HIV/AIDS among senior high-school students in Shanghai, China. We selected 1950 students from 10 senior high schools in Shanghai, from whom 968 students were selected at random for the intervention group and 982 students for the control group. The same questionnaires were carried out before intervention, one month and one year later in both the groups. In the intervention group, the knowledge score of reproductive health, HIV/AIDS and sexually transmitted disease rose from 21.66 to 31.72 one month later (P < 0.001). After one year it was still 30.97, and there was no significant difference between one month and one year (P > 0.05). The behaviour intention to HIV/AIDS prevention, such as condom use during sexual intercourse also changed before and after the intervention. After both the one month and one-year follow-up intervention, we found that more students declared that they would use condoms during sexual intercourse when compared with the control group (P < 0.001). No change was seen in either knowledge or behaviour intention in the control group. These results showed that peer education on HIV/AIDS prevention among high-school students is both effective in promoting knowledge and in changing behaviour intention long term.

A comparative genomic analysis between human breast cancer and paired tumor lines derived from transplanation of tumor biopsies into NOD/SCID mice

Abstract #41

Background: Successful preclinical studies of experimental anticancer agents require model systems that recapitulate breast cancer biology and genomic abnormalities as accurately as possible. The use of primary human tumor explants engrafted into the humanized mammary fat pad of NOD SCID mice (HIM technique for "human in mouse") is promising in this regard, but the evidence that the genomic profile of the tumor is stable during serial translatation of human tumors into mice and between mouse passages has not beeen clearly demonstrated.&#x2028; Methods: 4th mammary glands of NOD/SCID mice were humanized by removing mouse mammary epithelia and implanting immortalized human breast fibroblasts. Human breast tumor tissues were dissociated into single cell suspensions and injected into the “humanized” mammary fat pads of NOD/SCID mice. Patient tumors were micro-dissected from the surrounding normal tissue by laser capture microdissection and tumor RNA and DNA was isolated. In addition, tumor RNA and DNA was isolated from xenografts at passage 1, 2, and 3. Agilent 4 x 44K whole genome expression array and 244K array-based comparative genomic hybridization (aCGH) was performed on established xenografts (passage 1-3) as well as the original tumor samples. Exon 9 and 20 of PIK3CA and exon 4 to 9 of TP53 were targeted for mutation detection since these genes are commonly mutated in human breast cancer.&#x2028; Results: To date, eight HIM tumor lines have been successfully established and serially passaged. The HIM number and source of tumor are as follows: HIM2 (primary tumor); HIM 3 (primary tumor); HIM 4 (abdominal wall metastasis); HIM 5 (brain metastasis from the patient used to establish HIM 2); HIM6 (primary breast cancer); HIM7 (chest wall metastasis); HIM 8 (chest wall metastasis); HIM9 (chest wall metastasis). Passage 3 HIM tumors serially transplanted in NOD/SCID mice have similar histopathological features to their original human counterparts (HCP). Sequence analyses of the eight HIM lines reveals mutations in the TP53 gene in three tumor lines and a mutation in PIK3CA gene in one tumor line that are also present in the HCP. aCGH analysis, where available, also demonstated that the positions of the major gene amplifications and deletions in HIM lines are also consistent with the HCP. Furthermore, aCGH shows that genomic structure of the grafts are stable with passage. Immunohistochemistry shows that HIM8 and its HCP are positive for HER2. Molecular subtyping by PAM50 gene list indicates that HIM 2 – 8 tumor lines and their HCP are basal type breast cancer. HIM9 tumor line and its HCP are luminal subtypes, although the proliferation signature was activated in the mouse graft.&#x2028; Conclusions: The HIM mouse system faithfully reproduces the genotypic features of the respective HCP's and is therefore a valuable research engine for the preclinical development of biomarkers, imaging techniques and for the assessment of novel therapeutic approaches, particularly for Basal-type breast cancer.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 41.

Targeted therapies for triple negative breast cancer based on TP53 status

Abstract #403

Background: Triple negative breast cancer (TNBC: negative for ER, PR and HER2) presents a significant clinical challenge. The frequent occurrence of mutations in TP53, the gene encoding the p53, in TNBC provides an opportunity for therapeutic intervention. p53 is required for cells to respond to DNA damage in the G1 phase of the cell cycle. Tumors with a defective p53 pathway fail to arrest (or undergo apoptosis) in G1 and rely on p53-independent pathways at S and G2 for their survival following DNA damage. Therefore, a potential therapeutic strategy for TP53 mutant tumors is to inhibit the S- and G2-checkpoints. Chk1 is a key regulator of both the S- and G2- checkpoints as such, p53 mutant cells are absolutely dependent on Chk1 activity to respond to DNA damage. This property makes Chk1 a potential therapeutic target in p53 defective tumors. Therefore, we tested the combination of irinotecan (DNA damaging agent) and UCN-01 (non-specific Chk1 inhibitor) in a preclinical model of TNBC. This combination was chosen based on preliminary results obtained in patients with TNBC on a Phase I trial conducted at our institution. UCN-01 is also a potent inhibitor of PDK1 and therefore inhibits the PI3K pathway. Given that PTEN is frequently deficient in TNBC, we also monitored components of the PI3K pathway in our preclinical model of TNBC.&#x2028; Material and Method: Tumor biopsies from patients with TNBC were engrafted into the humanized mammary fat pad of immunodeficient NOD/SCID mice. TP53 was sequenced in each engrafted tumor explant and the integrity of the p53 pathway was determined by monitoring p53 stabilization and p21 induction following DNA damage. Three independent TNBC tumor explants, one wild-type and two mutant for TP53 were analyzed for their response to irinotecan and UCN-01 either as single agents or in combination. UCN-01 was administered 24h post irinotecan in mice treated with the combination. Mice were sacrificed 48 h later and tumors were harvested and analyzed for cell cycle arrest (geminin, pCdk1), DNA damage (pChk1, gamma H2AX), apoptosis (cleaved caspase 3), checkpoint bypass (pHistone H3) and the PI3K pathway (pS6) by Western blotting and immunohistochemistry.&#x2028; Results: Expression profiling revealed that the characteristics of the tumor are preserved in the tumor explants suggesting this is a valid model system to study experimental therapy for TNBC. Irinotecan induced similar levels of DNA damage in TP53 wild-type and TP53 mutant TNBCs. UCN-01 potently inhibited levels of pS6 independent of p53 status. Strikingly, the combination of irinotecan and UCN-01 selectively induced checkpoint bypass and apoptosis in p53 mutant TNBCs.&#x2028; Conclusion: p53 status is a significant predictor of response to combination therapies involving DNA damage followed by Chk1 inhibition. Tumors, like TNBC, that frequently lack a functional p53 pathway may be effectively treated using this strategy. Studies are underway to test different chemotherapy agents and more selective Chk1 and PI3K inhibitors in this preclinical model of TNBC.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 403.

Measurement of the e;{+}e;{-}-->bb[over ] Cross Section between sqrt[s]=10.54 and 11.20 GeV

We report e;{+}e;{-}-->bb[over ] cross section measurements by the BABAR experiment performed during an energy scan in the range of 10.54 to 11.20 GeV at the SLAC PEP-II e;{+}e;{-} collider. A total relative error of about 5% is reached in more than 300 center-of-mass energy steps, separated by about 5 MeV. These measurements can be used to derive precise information on the parameters of the Upsilon(10860) and Upsilon(11020) resonances. In particular we show that their widths may be smaller than previously measured.

310 MARKER-GENE EXCISION IN TRANSGENIC CLONED SOMATIC CELLS AND EFFECTS ON RECLONED EMBRYO DEVELOPMENT IN CATTLE

Recently, it has become common to produce transgenic cattle by somatic cell nuclear transfer. As a major step, donor cells are transfected with expression vectors that contain not only the target gene but also marker genes such as neomycin resistant gene (neoR) used for subsequent cell screening. However, such markers in transgenic animals may be undesirable for further researches (Kuroiwa et al. 2004 Nature Genetics 36, 775–780). Therefore, the aim of this study was to excise the marker gene (neoR) in transgenic cattle by using transiently expressed CRE recombinase. Initially, the presence of loxP sites flanking neoR was confirmed in fibroblast cells derived from human lysozyme transgenic cloned cattle. By using cassettes from plasmids PBS185, pIRES-EGFP and pIREShyg3, IRES-EGFP element was inserted downstream of the CRE coding region, and the co-expression vector, which permits translation of GFP and CRE from one messenger RNA, was constructed. Then transgenic fibroblast cells were transfected by the CRE expression vector in circular format by Lipofectamine™ 2000 and screened by FACS after 48 h. GFP positive cells were selected to culture for 7 to 9 days, and removal of neoR was confirmed by PCR with 2000 to 3000 cells from each colony and the remaining cells used as donors for recloning. Then cleavage and blastocyst rate were evaluated; neoR excision was identified by single blastocyst PCR. Some blastocysts were harvested for differential staining and some used to conduct embryo transfer to evaluate in vitro and in vivo developmental ability. Data were analyzed using SAS (version 9.1) with one-way ANOVA. All experiments were replicated at least three times. We confirmed that loxP sites are correctly located at two sides of neoR. After transfection, neoR was removed from transgenic cloned fibroblast cells and cre was found to be expressed transiently. Additionally, neoR excision was confirmed by single blastocyst PCR. Furthermore, no significant difference was found on cleavage (P = 0.15) and blastocyst rate (P = 0.73) between cloned embryos when using neoR free donors and neoR included donors. The differential staining study showed similar numbers in terms of total cell number (P = 0.69) and the ratio of ICM to total cell number (P = 0.96). After embryo transfer, successful establishment of pregnancies were observed and pregnancy rate on Day 90 and Day 120 (Day 1 is the 1st day after embryo transfer) are similar with control (P > 0.05). In conclusion, we successfully excised resistant marker gene from transgenic cloned cattle by transient expression of CRE recombinase and we expect it will benefit bioreactor and animal transgenic research in the future.

The calcium-conducting ion channel transient receptor potential canonical 6 is involved in macrophage inflammatory protein-2-induced migration of mouse neutrophils

AIM

The role of the calcium-conducting ion channel transient receptor potential canonical 6 (TRPC6) in macrophage inflammatory protein-2 (MIP-2) induced migration of mouse neutrophils was investigated.

METHODS

Neutrophil granulocytes isolated from murine bone marrow of wild-type (TRPC6+/+) and TRPC6 knockout (TRPC6)/)) mice were tested for the presence of TRPC6 channel expression using quantitative real-time polymerase chain reactions and immunocytochemistry. The effect of different stimuli (e.g. MIP-2, 1-oleoyl-2-acetyl-sn-glycerol, formyl-methionyl-leucyl-phenylalanin) on migration of isolated neutrophils was tested by two-dimensional (2D) migration assays, phalloidin staining and intracellular calcium imaging.

RESULTS

We found that neutrophil granulocytes express TRPC6 channels. MIP-2 induced fast cell migration of isolated neutrophils in a 2D celltracking system. Strikingly, MIP-2 was less potent in neutrophils derived from TRPC6)/) mice. These cells showed less phalloidin-coupled fluorescence and the pattern of cytosolic calcium transients was altered.

CONCLUSIONS

We describe in this paper for the first time a role for transient receptor potential (TRP) channels in migration of native lymphocytes as a new paradigm for the universal functional role of TRPs. Our data give strong evidence that TRPC6 operates downstream to CXC-type Gq-protein-coupled chemokine receptors upon stimulation with MIP-2 and is crucial for the arrangement of filamentous actin in migrating neutrophils. This is a novel cell function of TRP channel beyond their well-recognized role as universal cell sensors.

57 NUCLEAR TRANSFER WITH RABBIT EMBRYONIC STEM CELLS: SERUM-STARVATION IMPROVES THE QUALITY OF CLONED EMBRYOS

Rabbit cloning by NT with somatic cells is so far a rather inefficient process. However, this technology is urgently required to generate rabbits with a humanized immune system as a source of human polyclonal antibodies. Embryonic stem cells (ESCs) have a number of advantages over somatic cells as tools for cell-mediated transgenesis including long periods of proliferation in vitro, higher frequency of homologous recombination between exogenous and chromosomal DNA, and less requirements for reprogramming (Rideout et al. 2000 Nat. Genet. 24, 109–110). To improve rabbit cloning we have derived and characterized 19 putative rabbit ESC lines and tested cells from 6 lines as donors for NT. First, we assessed in vitro development of NT embryos. Blastocyst rates varied in the range of 6–68% depending on the particular cell line and passage number, but the quality of the resultant embryos was worse compared to NT embryos derived from adult fibroblasts [hatched blastocysts: 13/214 (6%) v. 36/86 (42%), respectively]. Transfer of NT embryos derived from the ESC line showing the highest development to blastocysts into recipients resulted only in implantations (70%, 7/10) but not in offspring. Assuming that poor quality of NT embryos derived from ESCs could be due to the incompatibility between cell cycles of donor and recipient cells we used serum starvation to make ESCs more suitable for nuclear transfer. Serum starvation of one of the ESC lines (0.5% FCS for 3 days) greatly improved the quality of cloned embryos compared to those derived from non-starved cells of the same ESC line as indicated by the high proportions of hatched [38/151 (25%) v. 4/153 (3%)] and attached [25/151 (17%) v. 0%] to the surface of a culture dish blastocysts. Moreover, some of these blastocysts grew in vitro for 14–25 days. Our study provides evidence that the quality of NT embryos derived from ESCs can be significantly improved using serum starvation of donor cells suggesting possible effect of this treatment on the cell cycle synchronization. We are currently testing whether serum starvation of ESCs would also improve post-implantation development of rabbit NT embryos. This work is supported by Roche Diagnostic GmbH.

Histone deacetylase inhibitor trichostatin A modulates cell cycles in A2780 human ovarian cancer cell lines

PURPOSE OF INVESTIGATION

To analyze the effect and mechanism of TSA on cell cycles in human ovarian cancer cells.

METHODS

cells were cultured in RPMI 1640 supplemented. Flow cytometry analysis and RT-PCR were used to examine the distribution of cell cycles and the level of P21(WAF/CIPI) mRNA.

RESULTS

TSA induced increase of the G2/M phase accompanied by decrease of the S phase and enhanced level of P21(WAF/CIPI) mRNA in a concentration and time-dependent manner in A2780 cells.

CONCLUSION

Trichostatin A affects the activity of cyclin-dependent kinase through increased expression of P21(WAF/CIPI) mRNA. TSA causes A2780 cell blockage in the G2/M phase and inhibits cell proliferation of A2780 cells. The minimum level of active TSA is 100 nM and the minimum time is 12 hours. The effect relies on time and concentration.

A novel sludge minimized biological nitrogen removal process for saline sewage treatment

This study reports a lab-scale evaluation of a new biological nitrogen removal process for saline sewage treatment, namely a SANI process (Sulfate reduction, Autotrophic denitrification and Nitrification Integrated process). The experimental system consisted of an up-flow anaerobic bed for sulfate reduction, an anoxic filter for autotrophic denitrification using dissolved sulfide produced in the up-flow anaerobic bed and an aerobic filter for nitrification. The system successfully operated for more than 180 days with an overall organic carbon removal efficiency of 95%, in which, 82% removal was contributed by the up-flow anaerobic bed operating at a HRT of 6 h, and 13% removal by the anoxic filter. An average COD removed /sulfate removed ratio was found to be 0.76 gCOD/gSO(4) or 2.28 COD/gSO(4)-S further confirming that the organic removal was mainly achieved by the sulfate reduction. In terms of nitrogen removal efficiency, the SANI system was found sensitive to the recirculation rate between the anoxic filter and the aerobic filter. A recirculation rate of 3Q was found to be optimal for achieving 74% of the total nitrogen removal. It was confirmed that the autotrophic denitrification was a major contributor to the total nitrogen removal in the SANI system. Sulfur balance analysis indicated that both the accumulation of elementary sulfur in the biomass and the loss of hydrogen sulfide were trivial. During the entire operation period (330 days to date), no sludge was wasted from any reactors in this system. This was further confirmed by the biomass balance simulation results that low biomass yields of sulfate reducing bacteria, autotrophic denitrifiers and nitrifiers contribute to the zero excess sludge discharge.

Microwave radiation processing of metallic glassy powders

In the present study we investigate the stability of Cu50Zr45Al5 and Ni59Ti16Zr20Sn5 glassy powders and the formation of the bulk metallic glassy samples by microwave heating in a single mode cavity (915 MHz) in the alternating magnetic field maximum. Metallic glasses exhibit low viscosity at temperatures close to the glass-transition which allows for the processing of glassy powders. Microwave heating being a volumetric heating has significant advantages over conventional heating in materials processing, such as substantial energy savings, high heating rates and process cleanness.

Measurement of the branching fractions of B-->D**(l) nu(l) decays in events tagged by a fully reconstructed B meson

We report a measurement of the branching fractions of B-->D**(l) nu(l), decays based on 417 fb(-1) of data collected at the Y(4S) resonance with the BABAR detector at the PEP-II e+e- storage rings. Events are selected by full reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D(*) pi)- m(D(*)) is performed to extract the signal yields of the different D** states. We observe the B-->D**l(-1)nu(l) decay modes corresponding to the four D states predicted by heavy quark symmetry with a significance greater than 5 standard deviations including systematic uncertainties.

Self-assembling peptide nanofiber as potential substrates in islet transplantation

Hypoxia and reoxygenation (H/R)-induced damage often happens soon after islets are transplantation. The process of islet isolation and purification causes the rapid onset of hypoxia. We sought to develop a functional scaffold to sustain the structure and function of islets as well as to recover some of the surface molecules damaged during isolation, seeking to improve islet transplantation outcomes. Self-assembling peptide nanofiber (SAPNF), a new type of substrate has been shown to be an excellent biological material for neuronal cell culture and tissue engineering in animals. In this study, we investigated the protective effect of SAPNF on damage to rat islets. Freshly prepared rat islets from male Sprague-Dawley rats were seeded in plates coated with (SAPNF-treated group) or without (control group) SAPNF. The islets were then divided into two groups culture under normoxia for 7 days versus exposure to hypoxia (< 1% O2) for 6 hours followed by reoxygenation for 24 hours. The results showed that SAPNF exhibited improving effects on viability and function of cultured islets, protecting the one from H/R-induced damage. In both groups, the stimulation index of SAPNF-treated groups were about two times the controls. SAPNF treatment decreased apoptotic rates of islet cells. These results suggested the usefulness of SAPNF to maintain the viability and function of rat pancreatic islets. SAPNF may be a potential scaffold for clinical islet transplantation.

Cloning, sequencing, and analysis of the full-length CDNA of rhesus monkey factor IX

OBJECTIVE

Coagulation factor IX (FIX) is a vitamin K-dependent serine protease, which plays a key role in the coagulation cascade. The rhesus monkey may be an indispensable substitute for humans in research of pig-to-human xenotransplantation, due to its close relationship. But the coagulation function concordance between rhesus monkey and human is unknown. In this study, we cloned the full-length cDNA of rhesus monkey FIX (rFIX) to investigate the genomic backgrounds of the coagulation systems.

METHOD

We cloned the full-length cDNA from the cDNA library of rhesus monkey liver tissue. Polymerase chain reaction was used to screen the positive clones. Based on a partial sequence obtained by cDNA library screening and a homologous sequence from the database, we designed a second pair of primers to obtain the full sequence. For further analysis of rFIX, we used several online ExPASy Proteomic tools.

RESULT

We obtained the full-length cDNA of rFIX, which has 2668 nucleotides, predicting an open reading frame of 1383 nucleotides corresponding to 461 amino acids. The deduced protein sequence indicated functional domains of signal peptide, Gla, two epidermal growth factor, and trypsin-like serine protease, which were consisted with those of human FIX (hFIX). Sequence alignments showed that rFIX is highly homologous to hFIX with nucleotide identity of 96% and amino acid identity of 97%.

CONCLUSION

We have report herein the full-length cDNA of rFIX. The high homology between rhesus monkey and human coagulation factor ensure the reliability and feasibility of rhesus monkey as a recipient in studies on coagulation disorders in xenotransplantation.