Reproductive development and function of female rats exposed to di-eta-butyl-phthalate (DBP) in utero and during lactation

Phthalates are environmental contaminants used in the production of plastics, cosmetics and medical devices. Studies on the effects of phthalates on female reproductive health are particularly sparse and mostly restricted to high-dose exposure in rats. In the present study, pregnant rats were treated with 100 mg/kg-d of di-eta-butyl-phthalate (DBP) or only the vehicle (control group), from GD 12 to GD 20 for evaluation of reproductive outcomes and fetal gonads analysis (F0), and from GD 12 to PND 21 to evaluate reproductive development and function on F1 female offspring. Results showed that all parameters were comparable between groups, although there was a significant increase in the fetal weight after DBP exposure. However, the body weight at birth was normal. Based on these data we can conclude that, in these experimental conditions, DBP did not disturb the reproductive development or function of female rats. (C) 2009 Elsevier Inc. All rights reserved.

Persistent Impairment of Testicular Histology and Sperm Motility in Adult Rats Treated with Cisplatin at Peri-Puberty

Cisplatin is one of the most widely used and effective chemotherapeutic agents for the treatment of several human malignancies. This study evaluated the effects of peri-pubertal cisplatin administration on several reproductive end-points and the reversibility of these effects in adulthood. Peri-pubertal Wistar male rats (45 days old) were divided into two groups: control (saline 0.9%) and cisplatin (1 mg/kg/day, 5 days/week, for 3 weeks, i.p.). The study was conducted in two steps and evaluations were performed at ages of 66 (post-pubertal age) and 140 (adult age) days on: (i) organ weights, serum gonadotropins and testosterone levels, sperm counts, motility and morphology, testicular histomorphometry, spermatogenesis kinetics, Sertoli cell number and in situ detection of apoptotic germ cells and (ii) sexual behaviour, fertility and intratesticular testosterone. At the end of cisplatin therapy, rats showed reductions in sperm production and reserves, sperm with progressive movement, tubular diameter, intratesticular testosterone and fertility potential, but increased numbers of TUNEL-positive seminiferous tubules, immotile sperm and pre-implantation losses compared with control. Moreover, cisplatin-treated post-pubertal rats displayed impaired testicular histopathology and sexual behaviour. Serum gonadotropins and testosterone levels, sperm morphology, spermatogenesis kinetics and Sertoli cell number were comparable between experimental groups at both ages. Alterations found in post-puberty were recovered at adulthood, except for sperm motility and damage to testicular histology. The persistence of these cisplatin effects, despite the unaltered fertility after natural mating in rats, may have implications for reproductive function of young boys undergoing cancer therapy, given the lower reproductive efficiency in human beings compared with rats.

Human Alveolar Bone-Derived Cell-Culture Behaviour on Biodegradable Poly(L-lactic Acid)

Poly(L-lactic acid) (PLA) is a polymer of great technological interest, whose excellent mechanical properties, thermal plasticity and bioresorbability render it potentially useful for environmental applications, as a biodegradable plastic and as a biocompatible material in biomedicine. The interactions between an implant material surface and host cells play central roles in the integration, biological performance and clinical success of implanted biomedical devices. Osteoblasts from human alveolar bone were chosen to investigate the cell behaviour when in contact with PLA discs. Cell morphology and adhesion through osteopontin (OPN) and fibronectin (FN) expression were evaluated in the initial osteogenesis, as well as cell proliferation, alkaline phosphatase activity and bone nodule formation. It was shown that the polymer favoured cell attachment. Cell proliferation increased until 21 days but in a smaller rate when compared to the control group. On the other hand, ALP activity and bone mineralization were not enhanced by the polymer. It is suggested that this polymer favours cell adhesion in the early osteogenesis in vitro, but it does not enhance differentiation and mineralization. (C) Koninklijke Brill NV, Leiden, 2009

Prevalence of Adverse Life Events, Depression and Suicidal Thoughts and Behaviour among a Community Sample of Young People aged 15-24 Years

Objective: To provide prevalence data on several key mental health indicators for young people aged 15 to 24 years. Methods: A cross-sectional household survey, using telephone recruitment followed by a postal pencil-and-paper questionnaire. The overall response rate was 67.3%. Results: Difficulties with interpersonal relationships are common causes of distress for young people, in particular problems with parents, problems with friends and relationship break-ups. Depressive symptomatology is common among young people with approximately one in eight males and one in four females reporting current depressive symptomatology. One in three young people reported that they had had suicidal thoughts at some time in the past, 1.2% of young people reported that they had made a plan on how to kill themselves in the four-week period prior to completing the survey and 6.9% of young people reported that they had tried to kill themselves at some time during their life time (4.2% of males and 9.0% of females). Conclusions and implications: The prevalence figures for the various mental health indicators presented in this paper represent good baseline information upon which to examine the progress over time of interventions designed to improve the mental health of young people.

The behaviour of phenylphosphine oxide containing polyimides in a water plasma following gamma-radiolysis

The surface oxidation of two polyimides containing fluorinated phenylphosphine oxide units, TOR-RC and TOR-RC ODPA, have been studied by (XPS) spectroscopy following gamma -radiolysis under vacuum or in air and subsequent treatment in a water plasma. The changes in the O 1s/C 1s ratios obtained from (XPS) analysis showed that on exposure to the water plasma the ratio increases and then levels to a constant value which is similar to that found for exposure to the plasma without prior gamma -radiation treatment. Evidence for the formation of phosphate species was also obtained from the (XPS) analyses. (C) 2001 Elsevier Science Ltd. All rights reserved.

Polymorphisms at the glutathione S-transferase GSTM1, GSTT1 and GSTP1 loci: risk of ovarian cancer by histological subtype

The phase II glutathione S-transferases (GSTs) GSTT1, GSTM1 and GSTP1 catalyse glutathione-mediated reduction of exogenous and endogenous electrophiles. These GSTs have broad and overlapping substrate specificities and it has been hypothesized that allelic variants associated with less effective detoxification of potential carcinogens may confer an increased susceptibility to cancer. To assess the role of GST gene variants in ovarian cancer development, we screened 285 epithelial ovarian cancer cases and 299 unaffected controls for the GSTT1 deletion (null) variant, the GSTM1 deletion (null) variant and the GSTP1 codon 104 A-->G Ile-->Val amino acid substitution variant, The frequencies of the GSTT1, GSTM1 and GSTP1 polymorphic variants did not vary with tumour behaviour (low malignant potential or invasive) or p53 immunohistochemical status. There was a suggestion that ovarian cancers of the endometrioid or clear cell histological subtype had a higher frequency of the GSTT1 and GSTM1 deletion genotype than other histological subgroups. The GSTT1, GSTM1 and GSTP1 genotype distributions did not differ significantly between unaffected controls and ovarian cancer cases (overall or invasive cancers only). However, the GSTM1 null genotype was associated with increased risk of endometrioid/clear cell invasive cancer [age-adjusted OR (95% CI) = 2.04 (1.01-4.09), P = 0.05], suggesting that deletion of GSTM1 may increase the risk of ovarian cancer of these histological subtypes specifically. This marginally significant finding will require verification by independent studies.

Cognitive behaviour therapy for the management of obsessive-compulsive disorder

Current research reflects conflict regarding best practice in the treatment of obsessive-compulsive disorder (OCD). The. present study reports on the psychological treatment of a 54-year-old woman diagnosed with OCD, and follows the implementation of pharmacological treatment. The study utilises both exposure and response prevention (ERP) and cognitive therapy (CT), although there was no attempt to compare these approaches in an experimental design. Measures of avoiding and neutralising behaviours were taken on three occasions across treatment. Measures were also taken of intrusive thoughts, appraisal of responsibility, and effective challenging, both across treatment and at follow-up. The results indicate that gains were made in addition to those reported following the implementation of medication. The results also suggest that the addition of CT to exposure and response prevention facilitates the extinction of neutralising behaviours.

Cancer culture: Epidemics, human behaviour and the dubious search for new risk factors

The rise of melanoma and the almost complete decline of stomach cancer clearly reflect disturbances of human culture during the 20th century. Environmental factors play a dominant role in the epidemiology of melanoma and many other malignancies.

Sex-biased hatching sequences in the cooperatively breeding Noisy Miner

The Noisy Miner Manorina melanocephala (Meliphagidae) is a cooperatively breeding bird species in which sons often remain on their natal home ranges and help one or both of their parents. In a population of Noisy Miners in SE Queensland, Australia, a molecular technique was used to explore adult and offspring sex ratios. and also hatching sequences. Among the adult population, there were 2.31 males for every female, and roughly 99% of helping was performed by males. At hatching and fledging, the population sex ratio was even, with exactly 57 males and 57 females. However, in 17 out of 18 broods the first egg to hatch was male, First-hatched males were significantly larger and heavier than their sisters just prior to fledging. Through their helping behaviour, large healthy sons could clearly enhance the future reproductive success of parents. and benefit the entire group. Sex-biased hatching sequences could potentially provide cooperatively breeding birds with a subtle and precise way of varying investment in the helping sex.

Optimal patch-leaving behaviour: a case study using the parasitoid Cotesia rubecular

1. Parasitoids are predicted to spend longer in patches with more hosts, but previous work on Cotesia rubecula (Marshall) has not upheld this prediction, Tests of theoretical predictions may be affected by the definition of patch leaving behaviour, which is often ambiguous. 2. In this study whole plants were considered as patches and assumed that wasps move within patches by means of walking or flying. Within-patch and between-patch flights were distinguished based on flight distance. The quality of this classification was tested statistically by examination of log-survivor curves of flight times. 3. Wasps remained longer in patches with higher host densities, which is consistent with predictions of the marginal value theorem (Charnov 1976). tinder the assumption that each flight indicates a patch departure, there is no relationship between host density and leaving tendency. 4. Oviposition influences the patch leaving behaviour of wasps in a count down fashion (Driessen et al. 1995), as predicted by an optimal foraging model (Tenhumberg, Keller & Possingham 2001). 5. Wasps spend significantly longer in the first patch encountered following release, resulting in an increased rate of superparasitism.

Behaviour rating scales for older people with dementia: which is the best for use by nurses?

There is increasing awareness of the importance of disruptive behaviour in people with dementia and the need for rating scales to accurately and reliably measure this behaviour. When rating scales are to be administered by nurses, scale characteristics must take into account the limitations of the nursing role and the nature of the environment in which nurses work. This paper reviews thirty-one rating scales that have been used to measure behaviour in dementia. From this analysis, five scales were identified as suitable for use by nurses when measuring disruptive behaviour in older people with dementia.

Mating behaviour and alternative oviposition sites for male eggs in the heteronomous hyperparasitoid Coccophagus gurneyi Compere (Hymenoptera : Aphelinidae)

The aphelinid parasitoid Coccophagus gurneyi Compere has unusual sex-related host relationships. Females are diploid and develop internally within mealybugs Pseudococcus calceolariae (Maskell). Males, in contrast, are haploid and hyperparasitic, developing on primary parasitoid larvae within the mealybugs. Furthermore, males have been claimed to be capable of either internal or external development, depending on the precise site of deposition of the haploid egg. This diversity of developmental pathways could indicate the existence of a sibling-species complex. We therefore quantified the mating and ovipositional behaviour of C. gurneyi, for comparison with that of an undescribed sibling species. We also checked whether the females deposit male eggs in alternative sites. The pattern of mating was found to be typical of mating behaviour in Coccophagus spp. and was consistent among all mating pairs, suggesting that the colony comprised one species. Further, the mating behaviour was significantly different from that of the undescribed sibling species. The site of male egg deposition varied and is apparently dictated by two factors; whether the mealybug is parasitised and, if so, the size of the parasitoid it contains. If the mealybugs were unparasitised or if the parasitoids within the mealybugs were small (< 0.53 mm), male eggs were deposited within the mealybug haemocoel. If the parasitoids were large (> 1.05 mm), male eggs were deposited within the parasitoids. These results support the claim of alternate host relationships and developmental pathways within males of C. gurneyi.

Maternal care and infant behaviour of the bridled nailtail wallaby (Onychogalea fraenata)

Bridled nailtail wallabies Onychogalea fraenata are endangered, medium-sized, nocturnal macropodids that persist at only one location in central Queensland, Australia. Characteristics of juvenile development, shelter use, anti-predator behaviour and maternal care were investigated in the wild using trapping, radio-tracking and spotlighting observations., Timing of developmental stages was identical to the pattern previously found in captivity, except for age at weaning which was much earlier in the wild. After young had left the pouch permanently at 17 weeks of age and weighing c. 800 g, they always spent the day concealed in dense cover, generally > 200 m from their mothers. Juveniles were also alone in > 50% of observations at night, and stayed closer to cover than did adult females. Young became independent of their mothers 7-8 weeks after permanent exit from the pouch and weighing c. 1800 g. Females with dependent juveniles changed their behaviour in ways likely to reduce predation on young. They reduced their home ranges, stayed closer to cover and became more wary than other females. Juveniles differed from adult females in their habitat use, anti-predator behaviour and shelter site preferences. Juveniles were more likely than adults to respond to threats by standing still or lying flat on the ground, whether or not they were in concealing cover. Juveniles used a wider range of smaller shelters than adults, and were less likely to use solid shelters such as hollow logs during the day. Because bridled nailtail wallabies have a 'hider' strategy of maternal care and the young rely on crypsis, successful breeding in the wild requires dense vegetation cover.