In vitro analysis of cidofovir and genetically engineered TK expression as potential approaches for the intervention of ColoAd1-based treatment of cancer

We have generated a novel oncolytic Adenovirus (Ad), ColoAd1, with significantly increased potency ( approximately 100-fold) relative to its parent viruses, Ad11p and Ad3, or to the clinically tested oncolytic Ad, ONYX-015. Although this agent has a significant increase in its therapeutic window relative to ONYX-015 or its parent viruses, its ability to intervene and control virotherapy in treated patient is an important safety consideration for a novel biological therapy, such as ColoAd1. As there are no approved treatments for Ad infections, we sought to define whether antivirals being used to experimentally treat Ad infections (cidofovir (CDV), ribavirin) had any activity against ColoAd1. In addition, we incorporated a well-described pro-drug converting enzyme, the herpes simplex virus-thymidine kinase (HSV-TK) gene, into the viral genome to test whether the expression of this enzyme directly from the virus could be exploited as a safety valve for arresting the viral infection in the presence of the pro-drug, ganciclovir. Both the antiviral drug, CDV, and the incorporation of the pro-drug-converting TK enzyme were validated as effective approaches to controlling ColoAd1 infection, and this represents an important advancement in the development of ColoAd1 as an anticancer treatment.

Testing for HIV and sexually transmissible infections within a mainly online sample of gay men who engage in group sex

INTRODUCTION

Group sex among gay men has been associated with other HIV risk behaviours. Gay men who engage in group sex may be at increased risk of infection with HIV and other sexually transmitted infections (STI).

METHODS

The Three or More Study (TOMS) of group sex among gay men utilised an anonymous, self-completed survey about participants' most recent occasion of group sex with other men and in-depth interviews with a small number of these survey participants. The 436 men who reported having engaged in group sex within the previous month were included in these analyses.

RESULTS

Among 436 men who engaged in group sex within the previous month, 32.5% reported unprotected anal intercourse (UAI) with non-regular, mostly HIV non-seroconcordant partners at this recent group sex encounter (GSE) and the majority reported other sex practices that are risk factors for STI other than HIV. Over one-third reported having been tested for HIV or other STI since their last GSE; those who had engaged in UAI at the GSE were more likely to have been tested (p = 0.008). Men who had a doctor with whom they were able to discuss their group sex activities had received a broader range of STI tests (p = 0.003).

CONCLUSION

Sex practices that risk the transmission of STI were common within this high-risk sample, whereas awareness of risk and the need for testing was high but not universal. Frank discussion with doctors of patients' group sex behaviour also enhanced decisions about adequate testing. Gay men in group sex networks are an appropriate priority for sexual health screening.

Anal human papillomavirus genotype diversity and co-infection in a community-based sample of homosexual men

OBJECTIVES

To determine the prevalence and risk factors for anal human papillomavirus (HPV) infection in community-based cohorts of homosexual men in Sydney, Australia.

METHODS

A cross-sectional study in consecutively presenting participants in the positive Health and Health in Men cohorts in 2005. HPV testing was performed on anal PreservCyt specimens collected from 316 homosexual men (193 HIV-negative, 123 HIV-positive) using the Digene Hybrid Capture 2 (HC-2) assay for detection of low-risk (LR) and high-risk (HR) genotypes. HPV genotype testing was also performed on a subset of 133 men (93 HIV-negative, 36 HIV-positive) using Roche Linear Array (LA) assay.

RESULTS

HC-2 detected HPV infection in 79% of men (LR 55%, HR 69%). HIV-positive men were more likely than HIV-negative men to have LR-HPV (OR 3.5, 95% CI 2.1 to 5.7) and HR-HPV (OR 5.5, 95% CI 3.0 to 10.2). LA detected HPV infection in 95% of men (LR 85%, HR 77%). HIV-positive men had a mean of 7.1 HPV types compared to 4.2 in HIV-negative men; the difference was significant for both LR-HPV (p<0.001) and HR-HPV (p<0.001). HPV-16 was detected in 36% of HIV-positive and 27% of HIV-negative men. There was no consistent trend in HPV prevalence with increasing age. HR-HPV detection was associated with anal bleeding for HIV-positive men and anal warts for HIV-negative men.

CONCLUSIONS

Anal HPV infection was nearly universal in this community-based sample of homosexual men. A wide variety of HPV genotypes were detected, and co-infection with multiple genotypes was common. Anal HPV infection is more prevalent and more diverse in HIV-positive than HIV-negative homosexual men.

Observation of two-source interference in the photoproduction reaction AuAu --> AuAurho0

In ultraperipheral relativistic heavy-ion collisions, a photon from the electromagnetic field of one nucleus can fluctuate to a quark-antiquark pair and scatter from the other nucleus, emerging as a rho{0}. The rho{0} production occurs in two well-separated (median impact parameters of 20 and 40 F for the cases considered here) nuclei, so the system forms a two-source interferometer. At low transverse momenta, the two amplitudes interfere destructively, suppressing rho{0} production. Since the rho{0} decays before the production amplitudes from the two sources can overlap, the two-pion system can only be described with an entangled nonlocal wave function, and is thus an example of the Einstein-Podolsky-Rosen paradox. We observe this suppression in 200 GeV per nucleon-pair gold-gold collisions. The interference is 87%+/-5%(stat.)+/-8%(syst.) of the expected level. This translates into a limit on decoherence due to wave function collapse or other factors of 23% at the 90% confidence level.

Indications of conical emission of charged hadrons at the BNL relativistic heavy ion collider

Three-particle azimuthal correlation measurements with a high transverse momentum trigger particle are reported for pp, d+Au, and Au+Au collisions at sqrt[s_{NN}]=200 GeV by the STAR experiment. Dijet structures are observed in pp, d+Au and peripheral Au+Au collisions. An additional structure is observed in central Au+Au data, signaling conical emission of correlated charged hadrons. The conical emission angle is found to be theta=1.37+/-0.02(stat)-0.07+0.06(syst), independent of p_{ perpendicular}.

System-size independence of directed flow measured at the BNL relativistic heavy-ion collider

We measure directed flow (v_{1}) for charged particles in Au+Au and Cu+Cu collisions at sqrt[s_{NN}]=200 and 62.4 GeV, as a function of pseudorapidity (eta), transverse momentum (p_{t}), and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all available model implementations, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to v_{1} in different collision systems, and investigate possible explanations for the observed sign change in v_{1}(p_{t}).

Forward neutral-pion transverse single-spin asymmetries in p + p collisions at sqrt[s] = 200 GeV

We report precision measurements of the Feynman x (xF) dependence, and first measurements of the transverse momentum (pT) dependence, of transverse single-spin asymmetries for the production of pi0 mesons from polarized proton collisions at sqrt[s] = 200 GeV. The xF dependence of the results is in fair agreement with perturbative QCD model calculations that identify orbital motion of quarks and gluons within the proton as the origin of the spin effects. Results for the pT dependence at fixed xF are not consistent with these same perturbative QCD-based calculations.

Growth inhibition of an established A431 xenograft tumor by a full-length anti-EGFR antibody following gene delivery by AAV

Therapeutic monoclonal antibodies continue to achieve clinical success for the treatment of many different diseases, particularly cancer. However, the production and purification of antibodies continues to be a time and labor-intensive process with considerable technical challenges. Gene-based delivery of antibodies may address this, via direct production within the host that achieves therapeutic levels. In this report, we validate the feasibility that gene-based delivery is a viable approach for efficacious delivery of antibodies in the preclinical and, presumably, clinical setting. We demonstrate high and sustained in vivo expression of the murine antihuman epidermal growth factor receptor antibody 14E1 following intramuscular delivery by adeno-associated virus (AAV) 2/1. Incorporating the Furin/2A technology for monocistronic expression of both heavy and light chains, we achieved sustained serum levels of full-length 14E1 peaking over 1 mg ml(-1) in athymic nude mice. In the A431 xenograft tumor model, 14E1 was capable of significantly inhibiting tumor growth and prolonging survival when AAV was administered prior to tumor challenge. Furthermore, 14E1 demonstrated significant antitumor efficacy against well-established tumors (approximately 400 mm(3)) when AAV was administered up to 20 days after tumor challenge. Here we demonstrate for the first time growth inhibition of a well-established tumor by a full-length antibody following delivery by AAV.

Self-report is a valid measure of circumcision status in homosexual men

OBJECTIVE

Misreporting of circumcision status may affect observed relationships between circumcision status and HIV or other sexually transmissible infections. As no data exist on the validity of self-reported circumcision status among homosexual men, we investigated the agreement between self-report and examination findings in a subgroup of participants in the Health in Men (HIM) study in Sydney, Australia.

METHODS

A subgroup of 240 participants in the community based HIM cohort study attending annual interview agreed to a brief genital examination by a trained study nurse who was unaware of their previous self-reported circumcision status.

RESULTS

Five participants reported being uncircumcised at baseline but were classified as circumcised on examination. All participants who self-reported being circumcised were found on examination to be circumcised. Three cases in which the examining study nurse was unsure of participants' circumcision status were excluded. Of the remaining 237 participants, 155 (65.4%) were classified as circumcised on examination, including five men who self identified as uncircumcised. Compared with examination, self-reported circumcision status resulted in a sensitivity of 96.8%, specificity of 100%, positive predictive value of 100% and negative predictive value of 94.3%. The overall agreement between circumcision status on examination and self-report was 97.9% (kappa score, 0.95; p<0.001)

CONCLUSION

Self-report was a valid measure of circumcision status in this group of predominantly Anglo gay-community-attached men. We believe our findings can be generalised to similarly aged gay-community-attached men in other developed countries.

Comparison between cells and cancer stem-like cells isolated from glioblastoma and astrocytoma on expression of anti-apoptotic and multidrug resistance-associated protein genes

This study is to explore and compare the features of the cells and cancer stem-like cells (CSCs) isolated from both glioblastoma and astrocytoma on expression of anti-apoptotic and multidrug resistance-associated protein (MRP) genes. As a result, the mRNA expression of livin, livinalpha and MRP1 was up-regulated in human CSCs from 2 times to 85 times, but the gene expression of MRP3 was down-regulated from 0.09 times to 0.5 times. After just differentiation the mRNA expression of livin, livinalpha and MRP3 was up-regulated from 9 times to 64 times, but the mRNA expression of MRP1 was down-regulated from 0.01 times to 0.03 times. It is a rare report that glioma stem-like cells can be induced successfully from a grade 2-3 astrocytoma tissue. The properties of glioblastoma and astrocytoma stem-like cells on anti-apoptotic and MRP genes are: anti-apoptotic gene livin and survivin are elevated in CSCs but are the most increased in just differentiated CSCs; MRP1 gene is significantly increased and MRP3 is decreased in CSCs, but when differentiating the MRP3 gene starts a remarkable increase in CSCs; the expression of anti-apoptotic and MRP genes shows no differences between the CSCs isolated from glioblastoma and astrocytoma tissues.

Sex work and risk behaviour among HIV-negative gay men

Gay men who engage in sex work may be at increased risk through risk behaviour outside the context of sex work. Among participants in the Health in Men (HIM) cohort of HIV-seronegative gay men in Sydney, 19.7% had ever engaged in sex work. Five percent reported being paid for sex in a six-month period during the study (2001-2006); a minority (18.3%) of these current sex workers reported unprotected anal intercourse (UAI) with clients and 62.0% reported UAI with any casual partners. The practice of sex work itself may not represent increased risk for HIV transmission but sex workers in this study were, nonetheless, at markedly increased risk in other aspects of their lives.

Distribution of two Asian-related coding SNPs in the MC1R and OCA2 genes

Very little is known about the genes and mechanisms affecting skin lightening in Asian populations. In this study, two coding SNPs, c.G1129A (R163Q) at the MC1R (melanocortin 1 receptor) gene and c.A1962G (H615R) at the OCA2 (oculocutaneous albinism type II) gene, were investigated in a total of 1,809 individuals in 16 populations from various areas. The Q163 and R615 alleles prevailed almost exclusively in East and Southeast Asian populations. Wright's F (ST) was 0.445 for R163Q and 0.385 for H615R among the 16 populations. The frequency of the Q163 allele was higher in Northeast Asians than in Southeast Asians. The frequency of the R615 allele was highest in South China and unlikely to be associated with levels of ultraviolet radiation. This allele may be a good marker to study the genetic affinity among East Asians because of its restricted distribution and marked difference in allele frequency.

Incidence and risk factors for urethral and anal gonorrhoea and chlamydia in a cohort of HIV-negative homosexual men: the Health in Men Study

BACKGROUND

Early detection and treatment of bacterial sexually transmitted infections has been advocated as an HIV prevention strategy.

AIM

To inform screening guidelines, the incidence and risk factors for urethral and anal gonorrhoea and chlamydia were studied in a prospective cohort of community-based HIV negative homosexual men in Sydney, New South Wales, Australia.

METHODS

All participants were offered annual screening for gonorrhoea and chlamydia (study-visit diagnoses) on urine and anal swabs using nucleic acid amplification. Participants also reported diagnoses of gonorrhoea and chlamydia made elsewhere between interviews (interval diagnoses). All diagnoses were summed to create a combined incidence rate, and detailed data on specific sexual practices with casual and regular partners were collected.

RESULTS

Among 1427 men enrolled, the combined incidence rates were 3.49 and 2.96 per 100 person-years for urethral and anal gonorrhoea, respectively; and 7.43 and 4.98 per 100 person-years for urethral and anal chlamydia, respectively. Urethral infections were associated with unprotected anal intercourse (UAI) with HIV-positive partners (hazard ratio (HR) = 2.58, 95% CI 1.10 to 6.05 for urethral gonorrhoea) and with frequent insertive oral sex (p for trend 0.007 for urethral chlamydia). Anal infections were associated with receptive UAI (p for trend 0.001 for both anal gonorrhoea and chlamydia) and other receptive anal sexual practices. Stratified analyses showed the independence of the associations of insertive oral sex with urethral infections and of non-intercourse receptive anal practices with anal infections.

CONCLUSION

Incident gonorrhoea and chlamydia were common. Risk behaviours for both urethral and anal infections were not restricted to UAI. Screening that includes tests for anal and urethral infections should be considered for all sexually active homosexual men, not just for those who report UAI.

65. CIRCUMCISION STATUS AND RISK OF SEXUALLY TRANSMITTED INFECTIONS IN THE HIM COHORT OF HOMOSEXUAL MEN IN SYDNEY, AUSTRALIA

Objectives: To examine circumcision status as an independent risk factor for prevalent and incident sexually transmitted infections (STIs) in the community-based Health in Men (HIM) cohort of homosexual men. Methods: Between 2001 and 2004, 1427 initially HIV-negative men were enrolled. Circumcision status was self-reported at baseline and was validated by clinical examination in a sub-sample of participants. All participants were tested annually for HIV and offered testing for other STIs including nucleic acid amplification tests (NAAT) for urethral gonorrhoea and chlamydia, and serology for syphilis and herpes simplex virus (HSV). Demographic information and past history of STIs was collected at baseline and detailed information on sexual risk behaviours was collected every 6 months. At annual face-to-face visits, participants reported diagnoses of STIs made in the previous 12 months. Results: At baseline, 66% of participants reported being circumcised; mostly as infants. Uptake of STI testing was high with over 90% of participants tested each year. On multivariate analysis, controlling for age and sexual risk behaviour, circumcision was not associated with baseline seropositivity to syphilis (p�=�0.34), HSV1 (p�=�0.33) or HSV2 (p�=�0.92), nor with a history of self-reported genital warts (p�=�0.18). There was also no association with incident bacterial urethral infections (p�=�0.67 & p�=�0.89 for gonorrhoea and chlamydia, respectively), self-reported incident genital warts (p�=�0.35), incident HSV1 (p�=�0.70) or incident HSV2 (p�=�0.36). However, circumcision was associated with a significantly reduced risk of incident syphilis after controlling for age, number of casual partners in the previous 6 months and unprotected anal intercourse according to partners' HIV status (HR�=�0.35, 95% CI 0.14-0.87, p�=�0.024). Conclusion: Circumcised men had a reduced risk of incident syphilis in this cohort. Although most STIs were not associated with circumcision, these data suggest that circumcision may have an effect on syphilis acquisition in homosexual men.

41. CIRCUMCISION AND RISK OF HIV SEROCONVERSION IN THE HIM COHORT OF HOMOSEXUAL MEN IN SYDNEY

Objectives: We examined circumcision as a risk factor for HIV seroconversion in a community-based cohort of homosexual men in Sydney. Methods: Between 2001 and 2004, 1427 initially HIV-negative men were enrolled. Circumcision status was self-reported at baseline, and self-report was validated by clinical examination during study visits in a sub-sample of approximately 300 participants. All participants were tested annually for HIV and offered testing for other sexually transmitted infections (STIs). Detailed information on sexual risk behaviours was collected every 6 months. Results: At baseline, 66% of participants reported being circumcised; mostly as infants. The proportion circumcised ranged from 83% in those aged 45 or more to only 50% in those aged less than 25 (p�<�0.0001). There were 49 HIV seroconversions through 2006, an incidence of 0.80 per 100 person years (PY). Anorectal gonorrhoea and anal warts were independent risk factors for HIV infection. Overall, being circumcised was not related to HIV infection (relative risk (RR) 1.07, 95% CI 0.56-2.06). After controlling for non-concordant unprotected anal intercourse (UAI), anorectal STIs and age, there remained no association with circumcision (RR�=�0.88, 95% CI 0.45-1.74). Only nine of the 49 seroconversions occurred among men who reported no receptive UAI, an incidence of 0.35 per 100PY. In this group, circumcision was also not associated with HIV seroconversion (RR�=�0.99, 95% CI 0.25-3.96). Conclusion: Overall, circumcision status was not associated with HIV seroconversion. In addition, analyses limited to those men who reported no receptive UAI, who are more likely to have been infected through insertive sex, suggest that circumcision may not reduce HIV risk even for insertive anal intercourse. Other preventive strategies are required to reduce HIV incidence in homosexual men.

363 FACTORS INFLUENCING PREGNANCY RATES FOLLOWING TRANSFER OF BOVINE IN VIVO EMBRYOS BIOPSIED FOR SEX DETERMINATION

Data collected from commercial embryo transfer programs in 63 farms in China during June 2002 to December 2005 was analyzed to examine the effects of various factors (biopsy, freezing, sample size, embryo development and quality, in vitro culture, and recipient quality) on pregnancy rates of in vivo-biopsied embryos. Embryos were flushed from superovulated dairy cattle and subjected to a biopsy for sexing determination using protocols and sexing kits supplied by AB Technology Ltd. Fresh embryos were implanted on the same day or frozen with AG freeze medium (AB Technology Ltd., Pullman, WA, USA) for later transfer. Recipients were synchronized with CIDA + PG protocols. Embryos were cultured in 6-well dishes containing 1.3 mL of holding medium (AB Technology Ltd.) in each well at room temperature (20–25�C) for examination of embryo survival in vitro. The chi-square test was used in statistic analysis. The implantation of fresh embryos after biopsy did not affect pregnancy rates (49.6%, 257/518) compared to that of non-biopsied fresh and frozen–thawed embryo groups (52.9%, 47/140 and 46.6%, 177/380, respectively). However, for biopsied embryos subjected to frozen and thawed procedures before implantation, particularly for those subjected to the removal of a larger biopsy, a reduced pregnancy rate was observed (41.8%, 297/710; P &lt; 0.01). Pregnancy rates among biopsied embryos at 3 different development stages (morula-early blastocyst, blastocyst, and expanded blastocyst) were not different. Similar results were found between embryo groups of grade 1 and 2. A significant decrease in pregnancy rate (0/10) was observed with embryos held in vitro for a longer period of time (&gt;5 h), suggesting detrimental effects of in vitro conditions on embryo survival. The highest pregnancy rate (68.0%) was observed in recipients synchronized for the first time before being implanted with biopsied embryos. Significant decreases in such rates were found in recipients synchronized for the second or third times or those with an abortion history at the first or second synchronization-implantation treatment (P &lt; 0.01). Better pregnancy rates (45.6%, 41/90; 46.1%, 76/165; and 45.5%, 5/11) were obtained for recipients implanted with biopsied embryos at Days 7.5, 8.0, and 8.5 post-heat detection, respectively, compared to 16% at Day 7 (3/18, P &lt; 0.05). It is concluded that mechanical treatment (cutting) does not reduce the survival of biopsied embryos; however, cryopreservation reduces their ability to survive in vivo. The analyses also suggest that holding embryos in vitro should not be longer than 5 h unless more favorable in vitro conditions can be provided. To achieve better results of implantation of biopsied embryos, embryo transfer should be performed during 7.5–8.5 days post-estrus, and the healthy recipients synchronized for the first time should be used.