Farming characteristics and self-reported health outcomes of Irish farmers.

Background: Irish farmers represent a 'high-risk' group for non-communicable diseases, which, arguably, pose a greater occupational health challenge for farmers. To date, there has been little exploration of the farming characteristics associated with farmers' poor health outcomes. Aims: To examine the relationship between farming and male farmers' self-reported health outcomes and to compare the study findings to national health studies to explore which factors specifically are associated with Irish farmers' poorer health outcomes relative to the general population. Methods: This cross-sectional survey research used self-reported quantitative data on the health outcomes and health behaviours of male farmers from the South-East of Ireland. Data were entered into SPSS and descriptive and binary regression techniques were used for data analysis. Results: There were 314 participants (99% response rate). Age, full-time farming and dairy farming significantly impacted self-reported health outcomes and health behaviours. There was a high prevalence of self-reported arthritis compared with the national average of Irish males. 'Younger' farmers (<45 years) were more likely to engage in harmful health behaviours such as smoking and 'binge-drinking' one or more times per week. Conclusions: This study identified self-reported patterns of risky lifestyle behaviours among particular subgroups of Irish farmers for whom targeted health interventions are warranted. Interventions are particularly important for younger farmers who may see themselves as invincible and impregnable to ill-health.

Stress responses to short-term intensified and reduced training in competitive weightlifters.

We sought to identify and evaluate the tolerance to, and consequences of, short-term variations in training load in competitive weightlifters. Seven international-level lifters performed 1 week of initial training followed by 2 weeks of intensified (INT: +100%, 36.5 ± 11.3 × 10(3) kg/week) and 1 week of subsequently reduced (RED: -25%) training within their annual program. After INT, but not RED, 90 min of weightlifting increased mRNA levels of chemokine (C-C motif) ligand 4 (CCL4), chemokine (C-X-C motif) receptor 4 (CXCR4) and cellular stress-associated DNA-damage-inducible transcript 4 (DDIT4) in peripheral blood mononuclear cells by 40-240%. Resting- and weightlifting-induced changes in plasma protein carbonyls, indicative of oxidative stress, but not pro-inflammatory CCL4 concentrations differed between INT and RED. Symptoms of stress (Daily Analysis of Life Demands of Athletes questionnaire) were reported as worse than normal more frequently during INT and RED than initial training. Global (negative) mood state increased during INT and declined during RED. Maximal snatch (-4.3 ± 3.7%) and vertical jump (-7.2 ± 6.5%), but not clean and jerk, were reduced after INT and restored after RED. Chemokine signaling may thus be part of the stress response to intense weightlifting and short-term reductions in training load support recovery from periodic INT training in weightlifters.

Site-specific water quality guidelines: 1. Derivation approaches based on physicochemical, ecotoxicological and ecological data.

Generic water quality guidelines (WQGs) are developed by countries/regions as broad scale tools to assist with the protection of aquatic ecosystems from the impacts of toxicants. However, since generic WQGs cannot adequately account for the many environmental factors that may affect toxicity at a particular site, site-specific WQGs are often needed, especially for high environmental value ecosystems. The Australian and New Zealand Guidelines for Fresh and Marine Water Quality provide comprehensive guidance on methods for refining or deriving WQGs for site-specific purposes. This paper describes three such methods for deriving site-specific WQGs, namely: (1) using local reference water quality data, (2) using biological effects data from laboratory-based toxicity testing, and (3) using biological effects data from field surveys. Two case studies related to the assessment of impacts arising from mining operations in northern Australia are used to illustrate the application of these methods. Finally, the potential of several emerging methods designed to assess thresholds of ecological change from field data for deriving site-specific WQGs is discussed. Ideally, multiple lines of evidence approaches, integrating both laboratory and field data, are recommended for deriving site-specific WQGs.

Corticosterone levels of Atlantic puffins vary with breeding stage and sex but are not elevated in poor foraging years.

Corticosterone (CORT) levels in seabirds fluctuate across breeding stages and in different foraging conditions. Here we use a ten-year data set to examine whether CORT levels in Atlantic puffins differ in years with high or low availability of capelin, the preferred forage species. Female puffins had higher CORT levels than males, possibly related to cumulative costs of egg production and higher parental investment. Puffins had higher CORT levels and body mass during pre-breeding than during chick rearing. Yearly mean chick growth rates were higher in years when adults had higher body mass and in years where adults brought chicks a lower percentage of non-fish (invertebrates/larval fish) food. Unlike most results from seabird species with shorter chick-rearing periods, higher CORT levels in puffins were not associated with lower capelin abundance. Puffins may suppress CORT levels to conserve energy in case foraging conditions improve later in the prolonged chick-rearing period. Alternatively, CORT levels may be lowest both when food is very abundant (years not in our sample) or very scarce (e.g., 2009 in this study), and increase when extra foraging effort will increase foraging efficiency (most years in this study). If these data primarily represent years with medium to poor foraging, it is possible that CORT responses to variation in foraging conditions are similar for puffins and other seabirds.

Role for endothelial nitric oxide synthase in nitrite-induced protection against renal ischemia-reperfusion injury in mice.

Nitrite is protective against renal ischemia/reperfusion injury (IRI); an effect due to its reduction to nitric oxide (NO). In addition to other reductase pathways, endothelial NO synthase (eNOS) may also facilitate nitrite reduction in ischemic environments. We investigated the role of eNOS in sodium nitrite (60 microM, 10 ml/kg applied topically 1 min before reperfusion)-induced protection against renal IRI in C57/BL6 wild-type (WT) and eNOS knockout (eNOS KO) mice subjected to bilateral renal ischemia (30 min) and reperfusion (24h). Markers of renal dysfunction (plasma [creatinine] and [urea]), damage (tubular histology) and inflammation (cell recruitment) were elevated following IRI in WT mice; effects significantly reduced following nitrite treatment. Chemiluminescence analysis of cortical and medullary sections of the kidney demonstrated rapid (within 1 min) distribution of nitrite following application. Whilst IRI caused a significant (albeit substantially reduced compared to WT mice) elevation of markers of renal dysfunction and damage in eNOS KO mice, the beneficial effects of nitrite were absent or reduced, respectively. Moreover, nitrite treatment enhanced renal dysfunction in the form of increased plasma [creatinine] in eNOS KO mice. Confirmation of nitrite reductase activity of eNOS was provided by demonstration of nitrite (100 microM)-derived NO production by kidney homogenates of WT mice, that was significantly reduced by L-NMMA. L-NMMA was without effect using kidney homogenates of eNOS KO mice. These results support a role for eNOS in the pathways activated during renal IRI and also identify eNOS as a nitrite reductase in ischemic conditions; activity which in part underlies the protective effects of nitrite.

Cutaneous human papillomavirus E7 type-specific effects on differentiation and proliferation of organotypic skin cultures.

BACKGROUND: A role for cutaneous human beta-papillomavirus (HPV) types as co-factors in the development of non-melanoma skin cancer has been postulated. Here we have investigated the effects of E7 expression on keratinocyte differentiation, proliferation and cell-cycle proteins in organotypic skin cultures. METHODS: Recombinant retroviruses containing the E7 genes from cutaneous HPV types 1, 4, 5, 8, 20, 38 and RTRX7 were produced that include types associated with benign and malignant lesions. Adult human primary keratinocytes were transduced with these recombinant retroviruses and differentiated into skin-equivalents using de-epidermalised human dermis. RESULTS: Expression patterns of the basal keratinocyte marker cytokeratin 14 (CK14) were not altered by any of the viral E7 types analysed. However, expression of the early and late differentiation markers CK10 and involucrin were markedly altered in HPV 1, 4 and 38 cultures. The highest proliferation rates in basal cell layers, as judged by BrdU and Ki67 staining, were observed in HPV 1, 4 and 38 cultures. Interestingly, co-expression of cyclin E and p16(INK4a) within the same cell of the suprabasal cell layers was observed only in cultures generated using E7 of HPV 5 or HPV 8. CONCLUSION: HPV types associated with either benign or malignant lesions perturb keratinocyte proliferation and differentiation in different ways. Moreover, expression of E7 from HPV 5 or HPV 8 seem able to overcome p16(INK4a) induced cell cycle arrest in a subset of keratinocytes.

Genetic structure of Melanotaenia australis at local and regional scales in the east Kimberley, Western Australia.

The Kimberley region of Western Australia possesses a poorly studied freshwater fish fauna with high endemism in an aquatic landscape subject to monsoonal floods and dry season isolation. In the first population genetic study of freshwater fish in this region, the authors tested the effects of geographic barriers on genetic structure at multiple spatial scales in east Kimberley populations of the western rainbowfish, Melanotaenia australis, the most widespread and abundant species in the region. Based on allozyme comparisons, hierarchical analysis of F(ST) revealed increasing genetic subdivision with spatial scale. Minimal genetic structure within creeklines demonstrated that wet season dispersal, rather than dry season isolation, determines genetic structure at small scales. At the scale of sub-catchments, a pattern of isolation by distance along creeklines was evident. Genetic subdivision between adjacent river systems was greater between rivers separated by a plateau than by lowlands. This implies greater connectivity of populations in lowland areas and may explain the greater similarity of the east Kimberly freshwater fish fauna with lowlands to the east than with the more rugged regions to the west. Similarly, greater connectivity between lowland populations may account for the on-average larger distribution of lowland Melanotaeniids.

Granulosa cell survival and proliferation are altered in polycystic ovary syndrome.

CONTEXT: Polycystic ovary syndrome (PCOS) represents the most common endocrine abnormality in women of reproductive age. The cause of PCOS remains largely unknown, but studies suggest an intrinsic ovarian abnormality. OBJECTIVE: The objective of the study was to test our hypothesis that differences in granulosa cell proliferation and apoptosis may underlie abnormalities that affect follicular development. DESIGN: Granulosa cells were prepared from follicular fluid aspirated from 4- to 8-mm follicles of unstimulated ovaries during routine laparoscopy or laparotomy from women with anovulatory PCOS and those with regular ovulatory cycles. SETTING: The study was conducted at a university hospital. PATIENTS: Fourteen women with anovulatory PCOS and nine women with regular ovulatory cycles participated in the study. MAIN OUTCOME MEASURES: Immunocytochemistry on granulosa cells to investigate apoptotic and proliferation rates, together with real-time RT-PCR to analyze gene expression profiles of apoptotic regulators, was measured. RESULTS: Significantly lower apoptotic rates were found in granulosa cells from patients with PCOS, compared with women with regular ovulatory cycles (P=0.004). Lower apoptotic rates were associated with decreased levels of the apoptotic effector caspase-3 (P=0.001) and increased levels of the anti-apoptotic survival factor cellular inhibitor of apoptosis proteins-2 in the PCOS group that were coupled to higher proliferation rates (P=0.032). Gene expression profiling confirmed the immunocytochemical findings. CONCLUSIONS: Our findings indicate that there are significant differences in the rate of cell death and proliferation in granulosa cell populations in PCOS patients. These are associated with decreased expression of apoptotic effectors and increased expression of a cell survival factor. These results provide new insights that may be useful in developing specific therapeutic intervention strategies in PCOS.

Overexpression of the Axl tyrosine kinase receptor in cutaneous SCC-derived cell lines and tumours.

The molecular mechanisms that underlie the development of squamous cell skin cancers (SSC) are poorly understood. We have used oligonucleotide microarrays to compare the differences in cellular gene expression between a series of keratinocyte cell that mimic disease progression with the aim of identifying genes that may potentially contribute towards squamous cell carcinoma (SCC) progression in vivo, and in particular to identify markers that may serve as potential therapeutic targets for SCC treatment. Gene expression differences were corroborated by polymerase chain reaction and Western blotting. We identified Axl, a receptor tyrosine kinase with transforming potential that has also been shown to have a role in cell survival, adhesion and chemotaxis, was upregulated in vitro in SCC-derived cells compared to premalignant cells. Extending the investigation to tumour biopsies showed that the Axl protein was overexpressed in vivo in a series of SCCs.

UV-B irradiation stimulates the promoter activity of the high-risk, cutaneous human papillomavirus 5 and 8 in primary keratinocytes.

Human papillomaviruses (HPV) have been implicated in the development of non-melanoma skin cancer (NMSC). HPV types 5 and 8 are strongly associated with NMSC in patients with the inherited disease Epidermodysplasia verruciformis (Ev). In these patients tumours arise predominantly on sun-exposed skin and consistently harbour HPV DNAs. To determine whether UV-B irradiation modulates the noncoding region (NCR) promoter activity of the Ev-HPV types 5, 8, 9, 14, 23, 24, and 25 we performed transient transfection assays with NCR luciferase reporter gene constructs in primary human epithelial keratinocytes (PHEKs) and in p53-null RTS3b cells. Each of the HPVs showed different basal NCR activity in both cell types and reacted differently upon UVB treatment and p53 cotransfection in RTS3b cells. The NCR of HPV5 and 8 were the only ones to be activated by UV-B in PHEKs. The stimulation of the NCR activity of the high-risk cutaneous HPV types 5 and 8 by UV-B irradiation may point to a role of this interaction in the development of NMSC.

Repair of UV-induced thymine dimers is compromised in cells expressing the E6 protein from human papillomaviruses types 5 and 18.

Ultraviolet (UV) irradiation is a major mutagenic environmental agent, causing the appearance of DNA adducts that, if unrepaired, may give rise to mutations. Ultraviolet radiation has been indicated as a major risk factor in the development of nonmelanoma skin cancers; however, recent reports have suggested that infections with human papillomaviruses, a widespread family of epitheliotropic DNA viruses, may also contribute to the tumorigenic process. Here, we investigated whether expression of the E6 protein from different HPV types interfere with the repair of thymine dimers caused by UV-B radiation. Results show that unrepaired DNA damage can be observed in UV-B-irradiated cells expressing the E6 protein of HPV types found in cervical and epithelial cancers. Moreover, such cells have the ability to overcome the G(1) cell cycle checkpoint induced as a result of unrepaired DNA.

Reduced apoptotic levels in squamous but not basal cell carcinomas correlates with detection of cutaneous human papillomavirus.

We have investigated the apoptotic levels and expression of the apoptotic inducer Bak in non-melanoma skin cancers. Squamous cell carcinomas of known human papillomavirus status from immunocompetent patients were analysed for the expression of the Bak protein, and the expression profile was compared both to the presence of apoptotic cells and the proliferation marker Ki-67. We demonstrate an inverse correlation between human papillomavirus positivity and Bak expression in squamous cell carcinomas, with concomitantly fewer apoptoic cells being detected in the human papillomavirus positive tumours. Bak expression was not observed in basal cell carcinomas irrespective of human papillomavirus status, suggesting that Bak only plays a role in signalling apoptosis in squamous, but not basal, cell cancers. No differences were observed in the proliferation rates between papillomavirus positive and negative squamous cell tumours. However, a significant decrease in the number of apoptotic cells was observed in human papillomavirus-positive squamous cell carcinomas which suggests that the virus may have significantly altered the relationship between proliferation and apoptosis in a proportion of these tumours.

Effects of micronutrient supplements on u.v.-induced skin damage.

Development of an orally-administered systemic agent that could reduce the effects of u.v. exposure on skin could potentially have a major effect on the incidence of skin cancers and photo-ageing. A number of micronutrients have been suggested to have metabolic properties that could induce this protection, and our data indicate that n-3 polyunsaturated fatty acids are particularly effective in this role. The mechanisms of action of n-3 polyunsaturated fatty acids appear to depend on their anti-inflammatory properties, acting to reduce the u.v.-induced release of cytokines and other mediators from a variety of skin cell types.

E7 proteins from oncogenic human papillomavirus types transactivate p73: role in cervical intraepithelial neoplasia.

In common with other E2F1 responsive genes such as p14(ARF) and B-myb, the promoter of p73 is shown to be positively regulated in cell lines and primary human keratinocytes by E7 proteins from oncogenic human papillomavirus (HPV) types 16, 18, 31 and 33, but not HPV 6. Mutational analysis revealed that transactivation of the p73 promoter by HPV 16E7 requires association with pRb. Expression of p73 in normal cervical epithelium is confined to the basal and supra-basal layers. In contrast, expression in neoplastic lesions is detected throughout the epithelium and increases with grade of neoplasia, being maximal in squamous cell cancers (SCC). Deregulation of expression of the N-terminal splice variant p73Delta2 was observed in a significant proportion of cancers, but not in normal epithelium. The frequent over-expression of p73Delta2, which has recognized transdominant properties, in malignant and pre-malignant lesions suggests a role in the oncogenic process in cervical epithelium.

Role of Bak in UV-induced apoptosis in skin cancer and abrogation by HPV E6 proteins.

Ultraviolet B (UVB) damage is recognized as the most important etiological factor in the development of skin cancer. Human papillomaviruses (HPV) have also been implicated in the disease, although the mechanism of action of these viruses remains unknown. We present evidence here that Bak protein is involved in signaling apoptosis in the skin in response to UVB damage, and that cutaneous HPV E6 proteins target and abrogate Bak function by promoting its proteolytic degradation both in vitro and in regenerated epithelium. Additionally, HPV positive skin cancers had undetectable levels of Bak in contrast to HPV negative cancers, which expressed Bak. This study supports a link between the virus and UVB in the induction of HPV-associated skin cancer and reveals a survival mechanism of virally infected cells.

P53 polymorphism in codon 72 and risk of human papillomavirus-induced cervical cancer: effect of inter-laboratory variation.

An association between codon-72 p53 polymorphism and risk of human papillomavirus (HPV)-induced cervical cancer has been found recently, but it has been difficult to replicate. In this study, we assess the impact of inter-laboratory variation in p53 genotyping on the validity of the proposed association. DNA specimens were randomly selected from 54 invasive, squamous cell carcinoma cases, 52 HPV-negative, and 39 HPV-positive controls from a previous case-control study in Brazil. Codon-72 polymorphism was blindly analyzed in three different laboratories. We calculated age- and race-adjusted odds ratios (OR) and 95% confidence intervals (CI) using logistic regression for gauging the association between p53 polymorphism and cervical cancer risk. The proportions of the Arg/Arg, Arg/Pro, and Pro/Pro genotypes varied substantially among laboratories with Kappa coefficients in the 0.49-0.63 range. When disagreement between labs was allowed, the OR for the Arg/Arg genotype, compared to other forms, was as low as 1.5 (95% CI: 0.5-3. 9). In contrast, the OR increased to 8.0 (95% CI: 2.3-28.5) after exclusion of discordant genotypes. Restricting the comparison to HPV-positive controls increased the magnitude of the relation appreciably. After exclusion of all discordant diagnoses, the OR was 21.5 (95% CI: 3.4-137.8), whereas with disagreed genotypes the association was not significant (OR = 2.9, 95% CI: 0.7-11.9). Homozygous codon-72 p53-Arg apparently confers a higher susceptibility to HPV-associated cervical tumorigenesis. However, exposure misclassification consequent to inter-laboratory variation in protocols may affect the ability to detect the association.

E6 proteins from diverse cutaneous HPV types inhibit apoptosis in response to UV damage.

In addition to their role in anogenital cancer, human papillomaviruses (HPVs) are also involved in the development of a range of cutaneous lesions. HPV types 5 and 8 are associated with the development of skin cancers in individuals with Epidermodysplasia verruciformis (EV). A broad spectrum of HPV types are also commonly found in non-melanoma skin cancers in immunocompromised individuals, such as organ transplant recipients. The skin cancers in EV and immunocompromised patients occur predominantly at body sites exposed to ultra violet (UV) radiation, pointing to a key role for UV in their development. Here we show that the E6 protein from a range of cutaneous HPV types effectively inhibits apoptosis in response to UV damage. This occurs in both p53 null and wild type cells and does not require p53 degradation.

The promoter of a novel human papillomavirus (HPV77) associated with skin cancer displays UV responsiveness, which is mediated through a consensus p53 binding sequence.

An aetiological role has been proposed for human papillomavirus (HPV) in skin carcinogenesis within the immunosuppressed patient population. To examine this possibility, we have focused on an HPV type that, to date, has been identified only in the cutaneous lesions of renal transplant recipients despite a high degree of sequence homology with other HPVs commonly found in warts in the general population. We report that the non-coding region of this virus, HPV type 77, contains a consensus binding site for the tumour suppressor protein p53, and we show by gel-retardation analysis that this sequence does indeed bind p53. Furthermore, using reporter gene assays, we demonstrate that HPV77 promoter activity is stimulated by UV radiation and that this response is mediated through the p53 binding site. This is the first report of a p53-dependent positive response element within a viral genome. Our results suggest a possible novel mechanism by which specific types of HPV might act as cofactors with UV radiation in cutaneous transformation.

Hippocampal volume is related to complexity of nesting habitat in Leach's storm-petrel, a nocturnal procellariiform seabird.

The hippocampal and telencephalon volumes of the nocturnal Leach's storm-petrel (Oceanodroma leucorhoa, n = 15) were compared with published data for food-storing and non-storing Passerines. The hippocampus to telencephalon ratio of Leach's storm-petrels is intermediate between food-storing and non-storing birds. Leach's storm-petrels taken from nesting burrows in wooded habitat had a larger relative hippocampal volume than those taken from burrows in an open meadow. Relative olfactory volume did not differ between woods and open-nesting storm-petrels. The larger relative hippocampal volume of storm-petrels may be associated with increased spatial demands of returning to their nests at night in the darker, more navigationally complex woods. It is not known whether the larger hippocampus in storm-petrels from the woods is due to selection on different subpopulations or whether experience in a more complex environment results in greater hippocampal volume. Hippocampal volume from the brain of one diurnal Procellariiforme, the northern fulmar (Fulmaris glacialis), fell within the range of non-storing species, which supports the view that hippocampal enlargement in the storm-petrel is related to the spatial demand of returning to the nest at night.