Topoisomerase II-alpha expression increases with increasing Gleason score and with hormone insensitivity in prostate carcinoma

AIM

To investigate and compare topoisomerase II-alpha expression in benign prostatic hyperplasia (BPH), prostate cancer of varying Gleason scores and hormone-insensitive prostate cancer.

METHODS

The immunohistochemical expression of topoisomerase II-alpha antibody in the above-mentioned diagnostic categories was investigated and compared.

RESULTS

Increased expression of topoisomerase II-alpha was seen in the prostate cancers of Gleason scores 7 and 8-10 (p = 0.000) compared with prostate cancers of Gleason score 6 and BPH (p = 0.245). Statistically significant differences were found in the topoisomerase II-alpha gene expression between prostate cancers categorised by Gleason Score. Also, increased expression of topoisomerase II-alpha was seen in the known hormone-resistant prostate carcinomas compared with prostate cancers with no hormone treatment in the subgroup with Gleason scores 8-10, which approached statistical significance (p = 0.081). No statistically significant difference was observed in topoisomerase II-alpha expression between the groups with BPH and prostate carcinoma of Gleason score 6 (p = 0.245).

CONCLUSION

Topoisomerase II-alpha expression was found to increase with the known prognostic marker Gleason score and with hormone insensitivity. Objective evidence is provided for clinical trials with drugs targeting topoisomerase II-alpha to be targeted to patients with prostate cancers of Gleason Score >6 and, in particular, prostate cancers of Gleason Scores 8-10.

Molecular pathology of prostate cancer

The molecular pathology of prostate cancer is complex; not only are multiple genes involved in its pathogenesis, but additional environmental factors such as diet and inflammation are also involved. The exhaustive research into prostate cancer to date has demonstrated a complex interaction of multiple genes and environmental factors, some of which may be more important in individual prostate cancer cases. This is an exciting era, with the emergence of new investigative tools such as DNA microarray technology and the application of the field of proteomics to the study of human cancers. Knowledge of genetic changes underlying the initiation, development, and progression of prostate cancer is accumulating rapidly. With increasing knowledge, it may be possible to distinguish indolent from aggressive prostate tumours by molecular fingerprinting. This review discusses the most consistently reported molecular pathological findings in hereditary and sporadic prostate cancer, together with new concepts and technologies.

Anxiogenic profile of AM-251, a selective cannabinoid CB1 receptor antagonist, in plus-maze-na??ve and plus-maze-experienced mice

The notoriously inconsistent effects of cannabinoids on anxiety-like behaviour may be explained by recent research on CB1 receptor knockout (CB1-KO) mice suggesting that cannabinoids exert bidirectional effects via the CB1 receptor (anxiolysis) and a novel rimonabant-sensitive neuronal cannabinoid receptor (anxiogenesis). This hypothesis is supported by the anxiogenic-like profile of AM-251, an analogue of rimonabant that is a potent and selective CB1 receptor antagonist but which, unlike rimonabant, has no activity at the novel receptor. As we have previously shown that rimonabant reduces anxiety-like behaviour in test-experienced animals only, the current study assessed the effects of AM-251 (1.5-3.0 mg/kg) in male Swiss-Webster mice that were either plus-maze-naïve or had been exposed undrugged to the apparatus 24 h prior to testing. Results confirmed that prior maze experience per se significantly increases behavioural indices of anxiety without altering measures of general activity. In maze-naïve mice, the lower dose of AM-251 (1.5 mg/kg) significantly reduced % open-arm time and increased grooming while the higher dose (3.0 mg/kg) additionally reduced open-arm entries and total head-dipping, and increased closed-arm returns. These anxiogenic-like effects were observed in the absence of significant changes in general activity levels. Although AM-251 had a very similar profile in maze-experienced animals, significant drug effects on open-arm avoidance measures were precluded by experientially-induced changes in behavioural baselines (i.e. 'ceiling' effects). Nevertheless, AM-251 again significantly reduced total head-dipping and increased grooming (3.0 mg/kg) and, unlike effects in naïve animals, both doses markedly reduced time spent on the centre platform and increased time spent in the enclosed arms. Against a baseline of almost total open-arm avoidance, the pattern of behavioural change in maze-experienced mice would also be consistent with an anxiogenic-like action of AM-251. Data are discussed in relation to previous findings with rimonabant, the putative existence of a novel non-CB1 neuronal cannabinoid receptor and, more generally, the behavioural pharmacology of plus-maze 'trial 2'.

The CCR5-delta32 mutation: impact on disease outcome in individuals with hepatitis C infection from a single source

BACKGROUND AND AIMS

Chemokines are small polypeptides, a major function of which is lymphocyte recruitment and trafficking. The aim of this study was to assess the involvement of inherited variations in CCR2, CCR5, and the ligand RANTES in determining disease outcome in hepatitis C virus (HCV) infected individuals.

METHODS

A total of 283 women, all exposed to HCV genotype 1b from a single donor, and including those who had spontaneously cleared the virus and those chronically infected, were genotyped for CCR2, CCR5, and RANTES polymorphisms. The frequencies of these polymorphisms were then compared with disease activity and severity.

RESULTS

CCR5, CCR2, and RANTES genotypes were compared with HCV polymerase chain reaction (PCR) status, alanine aminotransferase levels, and liver histology. There was no significant relationship between CCR2 or RANTES polymorphisms and disease outcome or severity. However, CCR5delta32 heterozygotes were more likely to have spontaneous clearance of the virus than those without the mutation (42% PCR negative v 28.3% negative; p = 0.044, odds ratio 1.83 (95% confidence interval 1.1-3.6)). Among the subgroup of DRB1*03011 negative individuals, previously found to be associated with more severe inflammation, the difference in histological inflammatory score (CCR5WT/WT = 4.9 v CCR5delta32/WT = 3.53; p = 0.043) was significant.

CONCLUSION

Heterozygosity for CCR5delta32 was shown to be significantly associated with spontaneous hepatitis C viral clearance and with significantly lower hepatic inflammatory scores in subgroups within this cohort. Both controls and the HCV population had similar heterozygosity frequencies.

Resistance to moxidectin and abamectin in naturally acquired Ostertagia circumcincta infections in sheep

AIM

To investigate the occurrence of resistance to macrocyclic lactone (ML) anthelmintics by Ostertagia circumcincta in lambs on a sheep and cattle property in the North Island of New Zealand.

METHODS

Thirty lambs were randomly allocated to one of five equal-sized groups, consisting of an untreated control and four treatment groups. The treatments, which were administered at the manufacturer's recommended dose rates, included oral moxidectin, oral abamectin (both at 0.2 mg/kg), an albendazole-levamisole combination, and an albendazole-levamisole-ivermectin combination. Post mortem worm counts were undertaken 7 days after treatment to determine the efficacy of each anthelmintic.

RESULTS

The albendazole-levamisole and albendazole-levamisole-ivermectin combinations both reduced O. circumcincta burdens to zero whereas for moxidectin and abamectin efficacies of only 72% and 29%, respectively, were recorded.

CONCLUSIONS

These results clearly demonstrated the occurrence of resistance to MLs by O. circumcincta. Although this is not the first occasion where resistance to this anthelmintic family has been detected in this parasite in sheep in New Zealand, it is the first instance that resistance to either moxidectin or abamectin has been reported.

Case-mix fails to explain variation in mastectomy rates: management of screen-detected breast cancer in a UK region 1997-2003

Wide variation in the surgical management of breast cancer exists at hospital, regional, national and international level. To demonstrate whether variation in surgical practice observed at aggregate level between breast units persists following adjustment for case-mix, individual patient-level data from the Trent Breast Screening Programme Quality Assurance database (1997–2003) was analysed. Expected case-mix adjusted mastectomy rates were derived by logistic regression using the variables tumour size, site and grade, patient age and year of presentation, employing the region's overall case-mix adjusted practice as the reference population. The region's 11 breast screening units detected 5109 (3989 invasive) surgically managed primary breast cancers over the 6-year period. A total of 1828 mastectomies (Mx) were performed (Mx rate 35.8%, 95% confidence interval: 34.5–37.1%). Significant variation in mastectomy rates were observed between units (range 25–45%, P<0.0001), and persists following case-mix adjustment (P<0.0001). Two-fold variation in observed to expected unit mastectomy rate coefficient is demonstrated overall (range 0.66–1.36), increasing to almost four-fold variation in cancers less than 15 mm diameter (range 0.55–1.95). Significant variation in surgery for screen-detected primary breast cancer is not explained by case-mix. Further research is required to investigate potential patient and professional causative factors.

A 6-month study of the efficacy and safety of tadalafil in the treatment of erectile dysfunction: a randomised, double-blind, parallel-group, placebo-controlled study in Australian men

The efficacy and safety of tadalafil for the treatment of erectile dysfunction (ED) were assessed in a 6-month, randomised, double-blind, placebo-controlled study. Australian men with mild, moderate or severe ED of organic, psychogenic or mixed aetiology were randomised to tadalafil 20 mg as needed (n = 93) or placebo (n = 47). Efficacy assessments included the international index of erectile function (IIEF) and the sexual encounter profile (SEP) diary. Tadalafil significantly improved erectile function compared with placebo (p < 0.001, all measures). At the end of the study, the mean per-patient proportion of successful sexual intercourse attempts (SEP question three) was 73.5% for patients treated with tadalafil and 26.8% for placebo-treated patients. Improved erections were reported by 78% of tadalafil-treated patients compared to 12.8% of placebo-treated patients. The most common treatment-emergent adverse events--headache and dyspepsia--were generally mild or moderate. Tadalafil was effective and well tolerated in Australian men with mild to severe ED.

Evidence for rescattering in intense, femtosecond laser interactions with a negative ion

It is now well established that energetic electron emission, nonsequential ionization, and high harmonic generation, produced during the interaction of intense, femtosecond laser pulses with atoms (and atomic positive ions), can be explained by invoking rescattering of the active electron in the laser field, the so-called rescattering mechanism. In contrast for negative ions, the role of rescattering has not been established experimentally. By irradiating F- ions with ultrashort laser pulses, F+ ion yields as a function of intensity for both linearly and circularly polarized light have been measured. We find that, at intensities well below saturation for F+ production by sequential ionization, there is a small but significant enhancement in the yield for the case of linearly polarized light, providing the first clear experimental evidence for the existence of the rescattering mechanism in negative ions.

Testicular growth hormone (GH): GH expression in spermatogonia and primary spermatocytes

Growth hormone (GH) gene expression is not restricted to pituitary somatotrophs and has recently been demonstrated in a variety of extrapituitary sites in mammals and the domestic chicken. The possibility that GH gene expression occurs in the male reproductive system of chickens was therefore examined, since GH has established roles in male reproductive function and GH immunoreactivity is present in the chicken testis. Using RT-PCR and oligonucleotide primers for pituitary GH cDNA, GH mRNA was shown to be present in the testes and vas deferens of adult cockerels. Although testicular GH mRNA was of low abundance (not detectable by Northern blotting), a 690 bp fragment of the amplified testicular GH cDNA was cloned and had a nucleotide sequence 99.6% homologous with pituitary GH cDNA. GH mRNA was localized by in situ hybridization in spermatogonia and primary spermatocytes of the seminiferous tubules, but unlike testicular GH-immunoreactivity, GH mRNA was not present in secondary spermatocytes, spermatids or spermatozoa. The presence of Pit-1 mRNA in the male reproductive tract may indicate Pit-1 involvement in GH expression in these tissues. The presence of GH receptor mRNA in the testis and vas deferens also suggests they are target sites for GH action. These results demonstrate, for the first time, expression of the pituitary GH gene in the testis, in which GH mRNA was discretely localized in primary spermatocytes. The local expression of the GH gene in these cells suggests autocrine or paracrine actions of GH during spermatogenesis.

Perioperative topical nitrate and sphincter function in patients undergoing transanal stapled anastomosis: a randomized, placebo-controlled, double-blinded trial

PURPOSE

The use of transanal stapling devices may impair continence because of digital dilatation and/or instrumentation. This study assessed the effect of pharmacological dilatation of the sphincter prior to stapler insertion.

METHODS

A randomized, placebo-controlled, double-blinded study of 60 patients undergoing transanal stapled anastomosis was undertaken. Consenting patients were randomly assigned to receive a single intraoperative dose of topical 0.2 percent nitroglycerin (glyceryl trinitrate) ointment or nitroglycerin-free placebo. All patients were assessed preoperatively and postoperatively by clinical methods (Wexner incontinence scores and examination), anorectal manometry by a station pull-through technique, and endoanal ultrasonography.

RESULTS

Intraoperative mean (+/-SEM) resting pressures (mmHg) were significantly reduced by nitroglycerin compared with prenitroglycerin levels (9.9 +/- 0.9 vs. 50.5 +/- 2.7; P = 0.002) or controls (56.0 +/- 3.2; P = 0.001). Twenty-one of the 28 controls (75 percent) but only 4 of the 32 patients in the nitroglycerin group (12.5 percent) required digital dilatation to insert the stapling instrument ( P = 0.003). Squeeze pressures were unaltered by the intervention but mean resting pressures were higher in the nitroglycerin group postoperatively (52.9 +/- 3.2 - 31.6 +/- 1.3 = 21.3 mmHg; 95 percent confidence interval, 14-27). Incontinence scores were lower in the nitroglycerin group at the 3-month (1.1 +/- 0.2 vs. 4.6 +/- 0.3; P = 0.003) and 12-month (0.9 +/- 0.1 vs. 4.4 +/- 0.3; P = 0.002) clinic visits.

CONCLUSION

Preoperative nitroglycerin dilatation protects sphincter function in patients undergoing transanal stapled anastomoses.

Antiphospholipid antibodies and subsequent thrombo-occlusive events in patients with ischemic stroke

CONTEXT

The presence of antiphospholipid antibodies (aPL) has been associated with vascular occlusive events. However, the role of aPL in predicting ischemic events, particularly recurrent ischemic stroke, is controversial.

OBJECTIVE

To evaluate the effect of baseline aPL positivity (ie, positivity for anticardiolipin antibodies [aCL], lupus anticoagulant antibodies [LA], or both) on subsequent thrombo-occlusive events, including recurrent stroke.

DESIGN, SETTING, AND PARTICIPANTS

The Antiphospholipid Antibodies and Stroke Study (APASS), a prospective cohort study within the Warfarin vs Aspirin Recurrent Stroke Study (WARSS), a randomized double-blind trial (N = 2206) conducted at multiple US clinical sites from June 1993 through June 2000 and comparing adjusted-dose warfarin (target international normalized ratio, 1.4-2.8) and aspirin (325 mg/d) for prevention of recurrent stroke or death. APASS participants were 1770 (80%) WARSS participants who consented to enroll in the APASS, with usable baseline blood samples drawn prior to randomization to the WARSS and analyzed for aPL status within 90 days of index stroke by a central independent laboratory. Quality assurance was performed on approximately 10% of samples by a second independent laboratory.

MAIN OUTCOME MEASURE

Two-year rate of the composite end point of death from any cause, ischemic stroke, transient ischemic attack, myocardial infarction, deep vein thrombosis, pulmonary embolism, and other systemic thrombo-occlusive events. The primary analysis assessed the outcome associated with aPL positivity within each WARSS treatment group separately, after risk-factor adjustment (since these aPL-positive vs aPL-negative comparisons were not randomized).

RESULTS

Of the 1770 APASS patients, 720 (41%) were classified as aPL-positive and 1050 (59%) as aPL-negative. There was no increased risk of thrombo-occlusive events associated with baseline aPL status in patients treated with either warfarin (relative risk [RR], 0.99; 95% confidence interval [CI], 0.75-1.31; P =.94), or aspirin (RR, 0.94; 95% CI, 0.70-1.28; P =.71). The overall event rate was 22.2% among aPL-positive and 21.8% among aPL-negative patients. There was no treatment x aPL interaction (P =.91). Patients with baseline positivity for both LA and aCL antibodies tended to have a higher event rate (31.7%) than did patients who tested negative for both antibodies (24.0%) (unadjusted RR, 1.36; 95% CI, 0.97-1.92; P =.07). Classification and regression tree analyses did not identify a specific LA test or aCL isotype or titer that was associated with increased risk of thrombo-occlusive event.

CONCLUSIONS

The presence of aPL (either LA or aCL) among patients with ischemic stroke does not predict either increased risk for subsequent vascular occlusive events over 2 years or a differential response to aspirin or warfarin therapy. Routine screening for aPL in patients with ischemic stroke does not appear warranted.

Development of an anaerobic capacity test for field sport athletes

Maximally accumulated oxygen deficit (MAOD) has been argued to be currently the best non-invasive method for estimating anaerobic capacity (Medbø et al., 1988, Ramsbottom et al., 1997). An easy to administer field test that could accurately predict MAOD, would be of great use to many field sport athletes and coaches. Fifteen male rugby union players undertook MAOD testing (99.4 +/- 16.9ml x kg(-1)) on a treadmill using a modification of procedure 3 as described by Medbø et al. (1988). All subjects also performed a 300m Shuttle Run Test (66.7 +/- 2.2s), run over a 20m distance. Analysis of the MAOD and 300m Shuttle Run Test time relationship revealed a significant correlation of r = -0.69 [p<0.01). Furthermore, a one-way analysis of variance (ANOVA) revealed that when subjects were split into 'good' and 'poor' groups based on 300m Shuttle Run Test times, the times distinguished between 'good' and 'poor' MAOD values (P<0.05). The findings of the present study support the validity of the 300m Shuttle Run Test as a useful estimate of anaerobic capacity in football athletes. Unexplained variance could be due to speed and agility factors associated with the 300m Shuttle Run Test. Methodological issues pertaining to the accurate assessment of MAOD are also discussed.

Primary prevention of childhood lead poisoning through community outreach

BACKGROUND

The prevalence of childhood lead poisoning has substantially decreased in Milwaukee, Wisconsin over the past decade. Nevertheless, by the mid 1990s, 30% of children were still found to have elevated blood levels.

OBJECTIVE

To extend the reach of the Milwaukee Health Department (MHD) to previously underserved families in 1 inner city neighborhood with extremely old housing, the Sixteenth Street Community Health Center (SSCHC) implemented, in 1995, the Community Lead Outreach Project (CLOP). Going door-to-door, CLOP attempted to identify children 6 months to 6 years old with elevated blood lead levels (BLL), referring those > or = 20 micrograms/dL to MHD and enrolling those with BLLs 10-19 micrograms/dL in a program of prevention education and environmental clean-up with the specific aim of preventing BLLs increasing to 20 micrograms/dL and above.

METHODS

A team of community outreach workers led by a nurse-coordinator visited, over a 4-year period, families in their homes in 13 census tracts surrounding the SSCHC. During the home visits, capillary blood samples for BLLs were drawn, environmental assessments and scoring were conducted, lead poisoning prevention education provided and repair and cleaning of household lead hazards demonstrated. For control and comparison, BLL data for the entire city by ZIP Code and provider were obtained from the Milwaukee Health Department. Odds ratios for changes in the proportions of children screened > or = 10 micrograms/dL were calculated and compared for the years 1996 through 1999. The odds ratios of changes for various populations were compared for significant differences using tests of homogeneity. To control for age confounding, proportions of elevated BBLs for all groups and for all years were age-standardized, using the direct method.

RESULTS

Over the entire study, 20.9% of the children screened had BLLs > or = 10 micrograms/dL and 3.0% were > or = 20 micrograms/dL. For 395 children with BLLs 10-19 micrograms/dL enrolled in the CLOP follow-up program, the mean BLL was 12.9 micrograms/dL. Mean levels at the first, second and third follow-up visits were 10.8, 10.3 and 9.8 micrograms/dL respectively, showing an overall decline of 3.1 micrograms/dL or 24%. At the first follow-up visit, 97% of the children tested were < 20 micrograms/dL while 76% were < 10 micrograms/dL. By the second follow-up visit, 100% were < 20 micrograms/dL. Initial environmental scores averaged 24.7, declining to 19.0 at first, 17.8 at second and 14.8 at third follow-up visits. For the entire CLOP population, the proportion of children testing > 10 micrograms/dL declined each year from 46.3% in 1996 to 22.5% in 1999. The geographic area in which CLOP operated recorded the highest screening penetration rate in the city: 61%. The odds ratio for CLOP clients to have elevated blood lead levels at the end of the study period, in contrast with the beginning, was 0.34 compared to 0.55 for the entire city and 0.75 for private physicians serving the same general population. Comparison of odds ratios showed the CLOP target population enjoyed a decrease in rate of elevated BLL 1.6 times that of the city-wide average, p-value = 0.016 and more than double that of the patients of area private providers.

CONCLUSIONS

We conclude that the Sixteenth Street Community Health Center Childhood Lead Outreach Project has successfully accessed populations of children with high rates of lead poisoning who had escaped more traditional screening venues and effectively intervened to reduce their BLLs to < 10 micrograms/dL. Moreover, CLOP produced impressive and unanticipated primary prevention benefits in the community at large. The demonstrated ability of community outreach workers to access high-risk populations and reduce exposure to lead hazards suggests the potential of this strategy for extension to other geographic areas, to the patients of private physicians and to address other prevalent, urban health problems like asthma, injuries and violence.