Perivascular nerve fibre proliferation: The consequence of prolonged straining

Four clinical cases are described in which a history of straining to achieve defaecation over many years, was associated with prolonged pelvic pain and the neuro-immunohistochemical observation of perivascular nerve fibre proliferation (PVNFP). Specimens of uterus, vagina, vulva and bladder have all demonstrated this novel histological feature. In three of the four cases, treatment with gonadotrophin releasing hormone agonists was associated with temporary improvement of the pain.

Effects of estradiol on the development of the bursa of Fabricius in Japanese quail

Effects of androgens on the development of the bursa of Fabricius are better understood than those of estradiol, despite the known sensitivity of the bursa to estradiol early in embryogenesis. The goal of this study was to determine the effects of one-time yolk injections of estradiol at day 4 of incubation on the development of the bursa and spleen as indices of treatment effects on the immune system. Follicle size and numbers in hatchling bursas were significantly reduced at 50 and 500 microg/egg, respectively. Additionally, distorted plicae and thicker epithelial layers surrounding the plicae were observed in day-old chicks at the same treatment levels. Adult bursas from birds embryonically exposed to estrogen were significantly larger than controls, suggesting an inhibition of natural bursal regression. Although estradiol altered the development of the bursa, the spleen appeared to be unaffected. The observed effects of estradiol on the development of the bursa indicate that this lymphoid organ may be a target for developmental disruption by estrogenic endocrine disrupting chemicals, though long-term consequences of embryonic exposure on immune function remain unknown.

Cancer survival in England and Wales at the end of the 20th century

Survival has risen steadily since the 1970s for most cancers in adults in England and Wales, but persistent inequalities exist between those living in affluent and deprived areas. These differences are not seen for children. For many of the common adult cancers, these inequalities in survival (the 'deprivation gap') became more marked in the 1990s. This volume presents extended analyses of survival for adults diagnosed during the 14 years 1986-1999 and followed up to 2001, including trends in overall survival in England and Wales and trends in the deprivation gap in survival. The analyses include individual tumour data for 2.2 million cancer patients. This article outlines the structure of the supplement - an article for each of the 20 most common cancers in adults, followed by an expert commentary from one of the leading UK clinicians specialising in malignancies of that organ or system. The available data, quality control and methods of analysis are described here, rather than repeated in each of the 20 articles. We open the discussion between clinicians and epidemiologists on how to interpret the observed trends and inequalities in cancer survival, and we highlight some of the most important contrasts in these very different points of view. Survival improved substantially for adult cancer patients in England and Wales up to the end of the 20th century. Although socioeconomic inequalities in survival are remarkably persistent, the overall patterns suggest that these inequalities are largely avoidable.

Effects of xenoestrogens on the differentiation of behaviorally-relevant neural circuits

It has become increasingly clear that environmental chemicals have the capability of impacting endocrine function. Moreover, these endocrine disrupting chemicals (EDCs) have long term consequences on adult reproductive function, especially if exposure occurs during embryonic development thereby affecting sexual differentiation. Of the EDCs, most of the research has been conducted on the effects of estrogen active compounds. Although androgen active compounds are also present in the environment, much less information is available about their action. However, in the case of xenoestrogens, there is mounting evidence for long-term consequences of early exposure at a range of doses. In this review, we present data relative to two widely used animal models: the mouse and the Japanese quail. These two species long have been used to understand neural, neuroendocrine, and behavioral components of reproduction and are therefore optimal models to understand how these components are altered by precocious exposure to EDCs. In particular we discuss effects of bisphenol A and methoxychlor on the dopaminergic and noradrenergic systems in rodents and the impact of these alterations. In addition, the effects of embryonic exposure to diethylstilbestrol, genistein or ethylene,1,1-dichloro-2,2-bis(p-chlorophenyl) is reviewed relative to behavioral impairment and associated alterations in the sexually dimorphic parvocellular vasotocin system in quail. We point out how sexually dimorphic behaviors are particularly useful to verify adverse developmental consequences produced by chemicals with endocrine disrupting properties, by examining either reproductive or non-reproductive behaviors.

Immunotoxicity of trenbolone acetate in Japanese quail

Trenbolone acetate is a synthetic androgen that is currently used as a growth promoter in many meat-exporting countries. Despite industry laboratories classifying trenbolone as nonteratogenic, data showed that embryonic exposure to this androgenic chemical altered development of the immune system in Japanese quail. Trenbolone is lipophilic, persistent, and released into the environment in manure used as soil fertilizer. This is the first study to date to assess this chemical's immunotoxic effects in an avian species. A one-time injection of trenbolone into yolks was administered to mimic maternal deposition, and subsequent effects on the development and function of the immune system were determined in chicks and adults. Development of the bursa of Fabricius, an organ responsible for development of the humoral arm of the immune system, was disrupted, as indicated by lower masse, and smaller and fewer follicles at day 1 of hatch. Morphological differences in the bursas persisted in adults, although no differences in either two measures of immune function were observed. Total numbers of circulating leukocytes were reduced and heterophil-lymphocyte ratios were elevated in chicks but not adults. This study shows that trenbolone acetate is teratogenic and immunotoxic in Japanese quail, and provides evidence that the quail immune system may be fairly resilient to embryonic endocrine-disrupting chemical-induced alterations following no further exposure posthatch.

Small intestinal cancer in England & Wales and Scotland: time trends in incidence, mortality and survival

BACKGROUND

Time trends in mortality from small intestinal cancer have not been studied for the 1990s.

OBJECTIVE

To examine secular trends in incidence of, mortality from, and survival from, small intestinal cancer in England & Wales and Scotland from 1975 to 2002, considering also histological type (incidence), subsite (incidence) and indices of social deprivation (incidence and survival).

METHODS

Data were extracted from the Scottish Cancer Registry database and the General Register Office for Scotland, and from the National Cancer Intelligence Centre at the Office for National Statistics for England & Wales.

RESULTS

Incidence rates for small intestinal cancer increased for both England & Wales and Scotland over the study period. They were highest among older individuals and generally greater for males than for females. Despite the increase in incidence rates, mortality rates from small intestinal tumours tended to remain stable over the study period, and the general trend was towards increasing survival. Indices of social deprivation were not obviously related to the incidence of small intestinal cancer and did not influence survival.

CONCLUSIONS

Incidence rates for small intestinal cancer for both England & Wales and Scotland increased in the last quarter of the 20th century, but survival rates improved and mortality rates declined.

Pancreatic cancer in England and Wales 1975-2000: patterns and trends in incidence, survival and mortality

BACKGROUND

Rates and time trends in mortality from pancreatic cancer vary considerably between countries.

AIM

To examine trends and patterns in the incidence of, and the survival and mortality from, pancreatic cancer in England and Wales from 1975 to 2000; in particular, whether incidence and survival rates are related to socio-economic deprivation.

METHODS

We calculated annual age-specific and overall age-standardized incidence and mortality rates by sex for pancreatic cancer in total, and by subsite. We also estimated survival by sex and age group and by subsite.

RESULTS

In males, the age-standardized rate fluctuated in the late 1970s, to peak at 13.0 per 100,000 in 1979, declined steadily by an average of 1.3% per year to around 10.3 per 100,000 in the mid-1990s and then levelled off. For females, the rate peaked at 8.4 per 100,000 in the late 1980s before declining and fluctuating around 7.7 per 100,000 in the late 1990s. Patterns and trends in mortality rates were closely similar to those in incidence, due to the very low survival rates: only 2-3% at 5 years from diagnosis. Survival rates improved only minimally over the period 1971-99. Incidence and mortality rates were slightly higher in both males and females living in the most deprived areas, but survival was not consistently related to socio-economic deprivation.

CONCLUSIONS

The incidence of, and mortality from, pancreatic cancer in England and Wales have fallen from peak levels observed in the 1970s and 1980s, and levelled off in the 1990s for both sexes; survival rates remain very low.

Consequences of endocrine disrupting chemicals on reproductive endocrine function in birds: establishing reliable end points of exposure

It has been difficult to establish reliable indices of exposure to endocrine disrupting chemicals (EDCs) appropriate for a variety of avian species because of a vast array of reproductive strategies. Data from mammals, reptiles and fish provide insight on likely mechanisms of action for EDCs. However, many of the effects of EDCs are weaker than the actions of the native hormones, making it difficult to assess adverse effects in domestic and wild birds. It is clear that differential sensitivity to EDCs exists across species, due to the timing and mode of exposure, compound toxicity and age of the individual. Our studies on EDCs are conducted in the quail model system, with focus on reproductive endocrine, neuroendocrine and behavioral responses. Studies have included EDC exposure, either by egg injection or via diet. Results from egg injection studies showed the following: (1) estradiol administered by embryonic day 12 demasculinized male sexual behavior, altered hypothalamic neurotransmitters and reduced hen day production and fertility in a dose dependent fashion, (2) methoxychlor (MXC) or vinclozolin impaired male sexual behavior in adult quail and (3) DDE exposure impaired reproductive and immune related end points. Two-generation studies were conducted on Japanese and northern bobwhite quail with dietary methoxychlor (MXC) exposure (0, 5 and 10 ppm) beginning in adults (P1), continuing in their offspring (F1), with F2 offspring raised on control diet. MXC exposure impaired male sexual behavior, hypothalamic catecholamines and plasma steroid hormones. Moreover, MXC exposure had reproductive consequences observable at both the lower and higher doses of MXC in F1 and F2 generations. These data demonstrate that embryonic EDC exposure interferes with sexual differentiation of neural systems that direct reproduction.

CURRENT TRENDS IN BLADDER CANCER IN ENGLAND AND WALES

PURPOSE

We examined trends in bladder cancer (BC) incidence, mortality and survival in England and Wales during a 30-year period.

MATERIALS AND METHODS

Age standardized incidence and mortality rates for BC, cohort incidence ratios, and 1 and 5-year relative survival from BC were calculated, and current trends were assessed.

RESULTS

Between 1971 and 1998 the total number of cases of BC increased by 57% from around 7,200 to almost 11,400. Between 1971 and 1998 directly age standardized incidence increased by 16% in males and 37% in females. Directly age standardized mortality decreased by 26% in males and showed little change in females during the same period. Five-year relative survival improved by around 15% points in the 1970s and early 1980s. However, there was less improvement in survival thereafter in that 5-year relative survival for patients diagnosed in 1993 to 1995 was 67% in men and 58% in women.

CONCLUSIONS

With an almost 60% increased incidence during the last 3 decades, BC incidence remains much higher in men but has increased more rapidly in women. There have been steady decreases in mortality rates, more marked in men than in women. Unusually, women have a significantly lower survival rate than men. Reasons for these patterns and trends are unclear. The trends in bladder cancer incidence by birth cohort suggest that the relationship with smoking may not be that strong and that other factors may be involved. Further research should focus on reasons for the recent increase in bladder cancer incidence in younger female birth cohorts.

Trends and socioeconomic inequalities in cancer survival in England and Wales up to 2001

We examined national trends and socioeconomic inequalities in cancer survival in England and Wales during the 1990s, using population-based data on 2.2 million patients who were diagnosed with one of the 20 most common cancers between 1986 and 1999 and followed up to 2001. Patients were assigned to one of five deprivation categories (from 'affluent' to 'deprived') using characteristics of their electoral ward of residence at diagnosis. We estimated relative survival up to 5 years after diagnosis, adjusting separately in each deprivation category for background mortality by age, sex and calendar period. We estimated trends in survival and in the difference in survival between deprivation categories ('deprivation gap') over the periods 1986-90, 1991-95 and 1996-99. We used period analysis to examine likely survival rates in the near future. Survival improved for most cancers in both sexes during the 1990s, and appears likely to continue improving for most cancers in the near future. The deprivation gap in survival between rich and poor was wider for patients diagnosed in the late 1990s than in the late 1980s. Increases in cancer survival in England and Wales during the 1990s are shown to be significantly associated with a widening deprivation gap in survival.