Can simple tank changes benefit the welfare of laboratory zebrafish Danio rerio?

This study examined the effects of simple changes in the tank environment on the wellbeing of laboratory-maintained zebrafish Danio rerio. Groups of D. rerio were either housed in stable environments (where they were maintained in the same tanks throughout the study) or in environments subject to change (where they were periodically moved to novel but identical tanks) and the effects of these treatments on morphometry, reproductive success and aggressive behaviour assessed. No effect of simple tank changes was found on body condition, reproductive output or aggression, for the periods of time studied, indicating that more complex scenarios in housing tank conditions are required for significant welfare benefits for captive D. rerio.

Stress and welfare in ornamental fishes: what can be learned from aquaculture?

The ornamental fish trade is estimated to handle up to 1·5 billion fishes. Transportation and handling of fishes imposes a range of stressors that can result in mortality at rates of up to 73%. These rates vary hugely, however, and can be as low as 2%, because they are generally estimated rather than based on experimental work. Given the numbers of ornamental fishes traded, any of the estimated mortality rates potentially incur significant financial losses and serious welfare issues. Industry bodies, such as the Ornamental Aquatic Trade Association (OATA), have established standards and codes of best practice for handling fishes, but little scientific research has been conducted to understand the links between stress, health and welfare in ornamental species. In aquaculture, many of the same stressors occur as those in the ornamental trade, including poor water quality, handling, transportation, confinement, poor social and physical environment and disease and in this sector directed research and some resulting interventions have resulted in improved welfare standards. This review considers the concept of welfare in fishes and evaluates reported rates of mortality in the ornamental trade. It assesses how the stress response can be quantified and used as a welfare indicator in fishes. It then analyses whether lessons from aquaculture can be usefully applied to the ornamental fish industry to improve welfare. Finally, this analysis is used to suggest how future research might be directed to help improve welfare in the ornamental trade.

Bisphenol A causes reproductive toxicity, decreases dnmt1 transcription, and reduces global DNA methylation in breeding zebrafish (Danio rerio).

Bisphenol A (BPA) is a commercially important high production chemical widely used in epoxy resins and polycarbonate plastics, and is ubiquitous in the environment. Previous studies demonstrated that BPA activates estrogenic signaling pathways associated with adverse effects on reproduction in vertebrates and that exposure can induce epigenetic changes. We aimed to investigate the reproductive effects of BPA in a fish model and to document its mechanisms of toxicity. We exposed breeding groups of zebrafish (Danio rerio) to 0.01, 0.1, and 1 mg/L BPA for 15 d. We observed a significant increase in egg production, together with a reduced rate of fertilization in fish exposed to 1 mg/L BPA, associated with significant alterations in the transcription of genes involved in reproductive function and epigenetic processes in both liver and gonad tissue at concentrations representing hotspots of environmental contamination (0.1 mg/L) and above. Of note, we observed reduced expression of DNA methyltransferase 1 (dnmt1) at environmentally relevant concentrations of BPA, along with a significant reduction in global DNA methylation, in testes and ovaries following exposure to 1 mg/L BPA. Our findings demonstrate that BPA disrupts reproductive processes in zebrafish, likely via estrogenic mechanisms, and that environmentally relevant concentrations of BPA are associated with altered transcription of key enzymes involved in DNA methylation maintenance. These findings provide evidence of the mechanisms of action of BPA in a model vertebrate and advocate for its reduction in the environment.

Multidisciplinary management of chronic heart failure: principles and future trends.

PURPOSE: Globally, the management of chronic heart failure (CHF) challenges health systems. The high burden of disease and the costs associated with hospitalization adversely affect individuals, families, and society. Improved quality, access, efficiency, and equity of CHF care can be achieved by using multidisciplinary care approaches if there is adherence and fidelity to the program's elements. The goal of this article was to summarize evidence and make recommendations for advancing practice, education, research, and policy in the multidisciplinary management of patients with CHF. METHODS: Essential elements of multidisciplinary management of CHF were identified from meta-analyses and clinical practice guidelines. The study factors were discussed from the perspective of the health care system, providers, patients, and their caregivers. Identified gaps in evidence were used to identify areas for future focus in CHF multidisciplinary management. FINDINGS: Although there is high-level evidence (including several meta-analyses) for the efficacy of management programs for CHF, less evidence exists to determine the benefit attributable to individual program components or to identify the specific content of effective components and the manner of their delivery. Health care system, provider, and patient factors influence health care models and the effective management of CHF and require focus and attention. IMPLICATIONS: Extrapolating trial findings to clinical practice settings is limited by the heterogeneity of study populations and the implementation of models of intervention beyond academic health centers, where practice environments differ considerably. Ensuring that individual programs are both developed and assessed that consider these factors is integral to ensuring adherence and fidelity with the core dimensions of disease management necessary to optimize patient and organizational outcomes. Recognizing the complexity of the multidisciplinary CHF interventions will be important in advancing the design, implementation, and evaluation of the interventions.

Ontogeny of sexual development in the roach (Rutilus rutilus) and its interrelationships with growth and age.

The roach (Rutilus rutilus) has become a sentinel species for the study of sexual disruption in wild fish populations as a consequence of exposure to endocrine disrupting chemicals (EDCs). Little is known, however, about the normal ontogeny of sexual development in this species. Here, we analyzed the ontogeny of sexual development in captive-bred roach and assessed how growth rate and fish size affected the timing of both sexual differentiation and sexual development over a 2-year period. Ovarian differentiation was first recorded at 68 days post-fertilization (dpf) and this preceded testicular differentiation (first recorded at 98 dpf). In contrast, sexual maturation occurred at an earlier age in males (300 dpf) compared with females (728 dpf). No differences in body size (length or weight) were recorded between male and female roach until the fish were 415 dpf. Studies on three populations of roach which grew at different rates showed that the timing of sexual differentiation was highly variable and more related to fish size than to fish age. Time to sexual maturation was also variable among populations but, subsequent to their first year of life, gonadal status was less well associated with fish size. Interestingly, the sex ratio of the population was biased towards females in populations that grew more rapidly during early life. The findings presented here provide a valuable foundation of work to support both field- and laboratory-based assessments on the effects of EDCs, and other stressors, on sexual differentiation and development in the roach.

Molecular basis of sex and reproductive status in breeding zebrafish.

The zebrafish (Danio rerio) is used extensively as a model species for studies on vertebrate development and for assessing chemical effects on reproduction. Despite this, the molecular mechanisms controlling zebrafish reproduction are poorly understood. We analyzed the transcriptomic profiles of the gonads of individual zebrafish, using a 17k oligonucleotide microarray, to define the molecular basis of sex and reproductive status in sexually mature fish. The gonadal transcriptome differed substantially between sexes. Among the genes overexpressed in females, 11 biological processes were overrepresented including mitochondrion organization and biogenesis, and cell growth and/or maintenance. Among the genes overexpressed in males, six biological processes were overrepresented including protein biosynthesis and protein metabolism. Analysis of the expression of gene families known to be involved in reproduction identified a number of genes differentially expressed between ovaries and testes including a number of sox genes and genes belonging to the insulin-like growth factor and the activin-inhibin pathways. Real-time quantitative PCR confirmed the expression profiles for nine of the most differentially expressed genes and indicated that many transcripts are likely to be switched off in one of the sexes in the gonads of adult fish. Significant differences were seen between the gonad transcriptomes of individual reproductively active females reflecting their stage of maturation, whereas the testis transcriptomes were remarkably similar between individuals. In summary, we have identified molecular processes associated with (gonadal) sex specificity in breeding zebrafish and established a strong relationship between individual ovarian transcriptomes and reproductive status in females.

Non-valvular atrial fibrillation and stroke: implications for nursing practice and therapeutics.

Atrial fibrillation (AF) is the most common sustained cardiac rhythm disturbance and is increasing in prevalence due to the ageing of the population, and rates of chronic heart failure. Haemodynamic compromise and thromboembolic events are responsible for significant morbidity and mortality in Australian communities. Non-valvular AF is a significant predictor for both a higher incidence of stroke and increased mortality. Stroke affects approximately 40,000 Australians every year and is Australia's third largest killer after cancer and heart disease. The burden of illness associated with AF, the potential to decrease the risk of stroke and other embolic events by thromboprophylaxis and the implications of this strategy for nursing care and patient education, determine AF as a critical element of nursing practice and research. A review of the literature was undertaken of the CINAHL, Medline, EMBASE and Cochrane Databases from 1966 until September 2002 focussing on management of atrial fibrillation to prevent thrombotic events. This review article presents key elements of this literature review and the implications for nursing practice.

Spironucleus vortens, a possible cause of hole-in-the-head disease in cichlids.

Hole-in-the-head disease is recorded in 11 discus Symphysodon discus Heckel, 1840 and 1 angelfish Pterophyllum scalare Lichtenstein, 1823 obtained from local aquarists within the Southwest of the UK. Spironucleus vortens Poynton et al. 1995, was isolated from the kidney, liver, spleen and head lesions of discus showing severe signs of the disease and from the intestines of all fish. The hexamitid was also recorded from the head lesions of the angelfish. The identity of these flagellates was confirmed as S. vortens on the basis of topographical features seen with the aid of SEM. A modified in vitro culture method was successfully developed for the detection, isolation and long-term maintenance of S. vortens. The flagellate was sub-cultured at 3 to 5 d intervals, new media being supplemented with fresh liver from Oreochromis niloticus (Linnaeus, 1757) free from infection. The results are discussed in relation to S. vortens as the causative agent for hole-in-the-head disease following systemic infection via the digestive tract.

Season-of-birth bias in association football.

In this longitudinal study, we assessed the frequency of birth dates for boys selected for the Football Association National School. Birthdays were divided into three periods of the year: January to April, May to August and September to December. We compared data over a 5 year period and concluded that there is indeed a bias towards selecting older children. Furthermore, analysis of separate data revealed a shift of bias when comparing two different start dates, namely September and January. Our findings show that the youngest children from the January start date (born September to December) are selected significantly more often than the youngest children from the September start date (born May to August). Interestingly, even when the influence of body mass was reduced, the selection bias towards the older players remained.

High-risk human papillomavirus is sexually transmitted: evidence from a follow-up study of virgins starting sexual activity (intercourse).

Genital human papillomavirus (HPV) infection is generally considered to be sexually transmitted. However, nonsexual spread of the virus has also been suggested. The goal of this study was to assess: (a) the role of sexual intercourse in the transmission of HPV; (b) the determinants for seroconversion; and (c) the correlation between HPV DNA, abnormal cervical cytology, and serological response to HPV16. One hundred virgins and 105 monogamous women were randomly selected from a population-based cohort study in Copenhagen, Denmark, in which the women were examined twice with 2-year interval (interview, cervical swabs, Pap smear, blood samples). The presence of HPV DNA was determined by GP5+/6+ primers based HPV-PCR-EIA. HPV 16 virus-like particles (VLP) antibodies were detected by ELISA. All of the virgins were both HPV DNA negative and seronegative to VLP16, except for one woman who was weakly HPV 6 DNA positive. Only those virgins who initiated sexual activity became HPV DNA positive and/or VLP16 positive. The most important determinant of HPV DNA acquisition was the number of partners between the two examinations. The only significant risk factor for HPV 16 VLP seroconversion among women acquiring HPV DNA was HPV type. Our results show that sexual intercourse is important in the transmission of HPV, and that HPV 16 VLP seroconversion and the development of cervical lesions only occur after HPV transmission. Remarkably, no cervical lesions were found in HPV 16 DNA positive women who had seroconverted. Although based on small numbers, this may suggest that the development of antibodies had a protective effect.

Low-grade fibromyxoid sarcoma and hyalinizing spindle cell tumor with giant rosettes: a clinicopathologic study of 73 cases supporting their identity and assessing the impact of high-grade areas.

Low-grade fibromyxoid sarcoma (LGFMS) is a rare sarcoma characterized by bland histologic features and a paradoxically aggressive clinical course. The hyalinizing spindle cell tumor with giant rosettes (HSCT) is a closely related tumor characterized by the presence of giant collagen rosettes. Only a single example of a metastasizing HSCT has been reported. A small subset of both LGFMS and HSCT display areas of increased cellularity and atypia which qualify as intermediate- to high-grade sarcoma; the significance of these features has not been definitively assessed. We present the clinicopathologic features of 77 cases of LGFMS and HSCT to determine the degree of overlap of these two lesions, their biologic behavior, and the significance of the occasional presence of intermediate- to high-grade sarcoma within both. The patients (33 female, 40 male) ranged from 3 to 78 years of age (median, 34 yrs). Fourteen cases occurred in patients less than 18 years of age. The tumors measured from 1 to 23 cm (median, 4.5 cm) and occurred predominantly in the trunk and lower extremities in both the deep (66 cases) and superficial (7 cases) soft tissues. In 15 cases, the tumor was present > 1 year before diagnosis. All tumors showed predominantly the typical hypocellularity and bland cytologic features of typical LGFMS; however, areas of hypercellularity and nuclear enlargement and hyperchromatism were identified in 12 of 73 (16%) and 7 of 73 (10%), respectively. Necrosis and mitotic activity >5/50 high-powered fields (HPF) were present in 6 of 73 (8%) and 5 of 73 (7%), respectively. Epithelioid areas were present in 33 of 73 (45%) and rosettes in 22 of 73 (30%). Follow up (54 cases; range, 2-192 mos; median, 24 mos; mean, 38 mos) showed 5 recurrences, 3 metastases, and 1 death. The diagnosis of LGFMS or HSCT was made prospectively in 51 patients; none had metastatic disease. Two of the metastatic tumors were LGFMS and one was a HSCT. LGFMS may occur more often in the pediatric population and show a much wider histologic spectrum than previously thought. A significant number of LGFMS possess inconspicuous collagen rosettes characteristic of HSCT, indicating that these two tumors are ends of a common spectrum rather than distinct entities. HSCT, like LGFMS, are low-grade sarcomas with metastatic potential. The presence of focal areas of intermediate- to high-grade sarcoma does not portend a worse outcome in the short term. The better prognosis reflected in this study compared with previous ones might reflect the fact that all were initially diagnosed as sarcomas and treated with aggressive surgery. The fact that the only three patients to develop metastatic disease were patients whose LGFMS or HSCT was identified retrospectively supports this concept.

The expanding clinical spectrum of desmoplastic small round-cell tumor: a report of two cases with molecular confirmation.

Desmoplastic small round cell tumor (DSRCT) is an aggressive neoplasm characterized by a consistent histological appearance, a unique immunohistochemical profile, and a specific chromosomal translocation. DSRCT is also hallmarked by distinctive clinical features. Most tumors arise in adolescent or young adult males, present as bulky abdominal masses, and diffusely spread along the peritoneal surface. We report two cases of DSRCT that do not fit this typical profile. One case involved the abdominal cavity of a 76-year-old woman. The other case arose in the parotid of a 22-year-old man. Histologically, the tumors showed the characteristic features of DSRCT. Immunohistochemically, the tumors showed positivity for cytokeratin, desmin, and neuron-specific enolase. Genetically, the tumors expressed the EWS-WT1 chimeric transcript. These two cases expand the differential diagnosis for poorly differentiated small-cell tumors that involve elderly patients or arise in the parotid. Moreover, they challenge the popular notion that DSRCT is a "blastomatous" tumor derived exclusively from the primitive mesothelium.

Human papillomavirus DNA detection in cervical specimens by hybrid capture: correlation with cytologic and histologic diagnoses of squamous intraepithelial lesions of the cervix.

Human papillomavirus (HPV) DNA detection in cervical specimens was correlated with cytologic and histologic diagnoses for 151 women who were referred to the Johns Hopkins Hospital colposcopy clinic for evaluation of an abnormal Pap smear. HPVs were identified as "high-risk" or "low-risk" by Hybrid Capture. The final disease status was categorized as high-grade squamous intraepithelial lesion (HSIL) by histology (n = 26), low-grade squamous intra-epithelial lesion (LSIL) by histology (n = 43), equivocal [histology negative, cytology atypical squamous cells of undetermined significance (ASCUS) or higher, n = 42], and negative (both histology and cytology negative, n = 40). Thirty-five percent of disease-negative women and 84% of the women with biopsy-proven or equivocal disease were HPV-positive. Ninety-two percent of the HPV-positive women harbored high-risk HPVs, either high-risk HPVs alone (77%) or high-risk HPVs along with low-risk HPVs (15%). High-risk HPVs predominated in disease-negative as well as disease-positive women. Collection of specimens with a cytobrush was more efficient for HPV DNA detection than collection by cervicovaginal lavage. Large amounts of HPV DNA correlated with presence of HSIL or LSIL. For detection of HSIL, considering only brush samples, the sensitivities of abnormal cytology (ASCUS or higher), of high-risk HPVs, and of the two combined were, respectively, 87, 93, and 100%; the corresponding specificities were 30, 30, and 20%. HPV DNA detection may be most beneficial in populations with low HPV prevalence.

PAPNET analysis of reportedly negative smears preceding the diagnosis of a high-grade squamous intraepithelial lesion or carcinoma.

One hundred fourteen cervical smears obtained from 18 women developing biopsy-proven high-grade squamous intraepithelial lesions and two with invasive squamous carcinomas were analyzed by two pathologists using the PAPNET neural network-based automated screening system (PAPNET Analyses A and B). The smears were originally reported as negative and had been previously rescreened and reclassified according to The Bethesda System. Using the PAPNET video displays of 128 potentially abnormal cellular images per smear, each reviewer (PAPNET A and B) determined whether a smear required conventional rescreening. Results of the PAPNET triage were compared with the reclassification diagnoses of the smears by conventional microscopy. PAPNET Analysis A selected eight (14%) smears reclassified as negative, 25 (69%) as atypical squamous cells of undetermined significance, and 15 (71%) as squamous intraepithelial lesions (SIL) for rescreening. In PAPNET Analysis A, two (10%) SILs were not selected for rescreening, and four (19%) were considered unsatisfactory for analysis. PAPNET Analysis B selected 21 (37%) smears reclassified as negative, 25 (69%) as atypical squamous cells of undetermined significance, and 18 (86%) as SIL for review. In PAPNET Analysis B, two (10%) SILs were missed, and one (5%) smear was unsatisfactory for analysis. Each PAPNET analysis selected smears for rescreening in 19 (95%) of 20 patients and detected SILs in 10 patients that were missed in the original screening. Using PAPNET, SILs would have been detected a median of 56 months (PAPNET A) and 62 months (PAPNET B) before their actual discovery. These preliminary data suggest that PAPNET may help detect SILs missed in routine cytologic screening.(ABSTRACT TRUNCATED AT 250 WORDS)

Vaginal intraepithelial neoplasia. Reproducibility of pathologic diagnosis and correlation of smears and biopsies.

Masked slides of 124 vaginal smears and 70 corresponding biopsies obtained from 45 patients with a reported cytologic diagnosis of vaginal intraepithelial neoplasia (VAIN) were examined by two pathologists to assess the interobserver reproducibility and histopathologic correlation of cytopathologic diagnoses of VAIN. The cytopathologic diagnoses by the two pathologists were identical in 94 (76%) cases and matched the originally reported diagnosis in 45 (46%) cases. The histopathologic diagnoses by the two pathologists agreed in 47 (67%) cases and matched the originally reported diagnosis in 35 (55%). The consensus cytopathologic and histopathologic diagnoses rendered by the pathologists agreed within one grade in 49 (70%) cases. A consensus histopathologic diagnosis of VAIN 2 was rendered in only 1 (10%) of 10 cases in which the cytopathologic diagnosis was VAIN 2. These results suggest that the cytopathologic and histopathologic grading of VAIN is moderately reproducible. Because (1) combining VAIN 2 and 3 under the diagnosis of high grade squamous intraepithelial lesion provided a slight improvement in diagnostic reproducibility and cytopathologic-histopathologic correlation and (2) the cytopathologic diagnosis of VAIN 2 was employed rarely and rarely confirmed histopathologically, we advocate the use of the term high grade squamous intraepithelial lesion to designate VAIN 2 and 3.

Gastric and esophageal Campylobacter pylori in patients with Barrett's esophagus.

Campylobacter pylori organisms were found with similar frequency in the stomachs of patients with Barrett's esophagus and in age- and sex-matched controls (10 of 26 vs. 11 of 26). Campylobacter pylori was also observed in esophageal Barrett's mucosa in some patients with gastric C. pylori, but not when gastric infection was absent (4 of 10 vs. 0 of 16). Campylobacter pylori was not detected in esophageal squamous mucosa from patients with Barrett's esophagus or in 25 non-Barrett's patients with gastric C. pylori and histologic changes of esophageal reflux. Overall frequency of ulceration in Barrett's esophagus was 35% (9 of 26), and frequency of ulceration was similar whether or not C. pylori was noted in gastric or Barrett's mucosa.