Husbandry stress exacerbates mycobacterial infections in adult zebrafish, Danio rerio (Hamilton).

Mycobacteria are significant pathogens of laboratory zebrafish, Danio rerio (Hamilton). Stress is often implicated in clinical disease and morbidity associated with mycobacterial infections but has yet to be examined with zebrafish. The aim of this study was to examine the effects of husbandry stressors on zebrafish infected with mycobacteria. Adult zebrafish were exposed to Mycobacterium marinum or Mycobacterium chelonae, two species that have been associated with disease in zebrafish. Infected fish and controls were then subjected to chronic crowding and handling stressors and examined over an 8-week period. Whole-body cortisol was significantly elevated in stressed fish compared to non-stressed fish. Fish infected with M. marinum ATCC 927 and subjected to husbandry stressors had 14% cumulative mortality while no mortality occurred among infected fish not subjected to husbandry stressors. Stressed fish, infected with M. chelonae H1E2 from zebrafish, were 15-fold more likely to be infected than non-stressed fish at week 8 post-injection. Sub-acute, diffuse infections were more common among stressed fish infected with M. marinum or M. chelonae than non-stressed fish. This is the first study to demonstrate an effect of stress and elevated cortisol on the morbidity, prevalence, clinical disease and histological presentation associated with mycobacterial infections in zebrafish. Minimizing husbandry stress may be effective at reducing the severity of outbreaks of clinical mycobacteriosis in zebrafish facilities.

Xenoma formation during microsporidial gill disease of salmonids caused by Loma salmonae is affected by host species (Oncorhynchus tshawytscha, O. kisutch, O. mykiss) but not by salinity.

Host species and salinity often affect the development of disease in aquatic species. Eighty chinook salmon Oncorhynchus tshawytscha, 80 coho salmon O. kisutch and 80 rainbow trout O. mykiss were infected with Loma salmonae. Forty of each species were reared in seawater and 40 in freshwater. The mean number of xenomas per gill filament was 8 to 33 times greater in chinook salmon than in rainbow trout (RBT). Coho salmon had a mean xenoma intensity intermediate to that of chinook salmon and RBT. In contrast to the differences between species, salinity had no significant effect on xenoma intensity in any of these host species. The onset of xenoma formation occurred at Week 5 postexposure (PE) for chinook salmon and RBT, and at Week 6 PE for coho salmon. RBT had cleared all visible branchial xenomas by Week 9 PE, whereas xenomas persisted in coho and chinook salmon at Week 9 PE. Histologically, xenomas were visible in the filament arteries of the branchial arch in chinook and coho salmon gills but were absent from RBT gills. Fewer xenomas were seen in the central venous sinusoids of RBT than in chinook and coho salmon. The lower xenoma intensity, shorter duration of infection and pathological characteristics, common to microsporidial gill disease in RBT, suggest a degree of resistance to clinical disease that is not seen in coho and chinook salmon.

Components of the Anger-hostility Complex as Risk Factors for Coronary Artery Disease Severity: A Multi-measure Study.

Different forms of anger and hostility have been implicated in the pathogenesis of coronary artery disease (CAD), though previous research has not measured all of these in one sample. To assess their relative predictive utility, a multi-measure study was undertaken of three adult outpatient groups: 97 men identified angiographically with stenosed coronary arteries; 28 men with valvular heart disorders in the absence of CAD; and 28 men attending a fracture clinic with no CAD present. Questionnaires measured: anger expression; anger experience; cynical hostility; 'Ho' hostility; neurotic hostility; neurotic disagreeableness; resentment; and suspiciousness. The pre-eminent anger-hostility correlate of CAD was found to be expressed anger, with years as a smoker and age also being independently related to disease severity. Thus, seven of these anger/hostility variables do not warrant similar attention as anger expression in CAD aetiology. Further research should identify coronary toxic components of anger expression and of socio-occupational environments that afford or constrain their occurrence.

Components of the anger-hostility complex and symptom reporting in patients with coronary artery disease: a multi-measure study.

Multiple anger and hostility variables were investigated for associations with coronary artery disease (CAD) symptoms and to examine if those relationships were different for disease severity.Atwo year follow-up study of97 men with stenosed coronary arteries was undertaken. Questionnaires measured: nine forms of anger and hostility; Type A behaviour; anxiety; depression; social support; and ninesymptom measures. CAD severity was derived from clinicians' ratings of coronary angiograms. Results are four fold: anger-hostility variables are relatively unimportant predictors of symptoms compared with anxiety and depression; psychosocial measures (except for expressed anger) are uncorrelated with CAD severity, though correlate numerously with CAD symptoms; symptoms are not distinguishable empirically in terms of frequency, intensity and duration with regard to type ('angina pain', 'tiredness' and 'breathlessness and restricted mobility'); finally, CADsymptoms are unrelated to CAD severity. In conclusion, components of the angerhostility complex are of limited use for predicting CAD symptoms. However, anger expression is of utility for differentiating between CAD symptoms and disease severity.

Congenital heart disease: a 10 year cohort.

In order to describe the epidemiology of congenital heart disease in Western Australia, a retrospective, population-based cohort study was conducted using data collected from multiple sources of ascertainment by the Western Australian Birth Defects Registry. The prevalence of congenital heart disease was 7.65 per 1000 total births. Nine per cent of all cases had a chromosomal disorder, another 17% had extracardiac defects in addition to congenital heart disease, and 75% had isolated congenital heart disease. Congenital heart disease was more common in Aboriginal compared with non-Aboriginal infants, and in multiple births compared with singletons. Compared with infants weighing 3000 to 3499 g, infants of lower birthweight were more likely to have congenital heart disease, and infants in the heaviest category (> or = 3500 g) were less likely to have congenital heart disease. Three per cent of all stillbirths were known to have a cardiac defect, as were 15.2% of neonatal deaths and 10.8% of post-neonatal deaths.

Superior vena caval thrombosis in a child: an uncommon presentation of idiopathic dilated cardiomyopathy.

A nine year old girl who presented with a thrombosis of the right internal jugular vein and superior vena cava was found to be in cardiac failure and to have a dilated cardiomyopathy. After transient improvement she deteriorated and was accepted for cardiac transplantation. Following transplantation her condition has been much improved.

Response of the patent ductus arteriosus to indomethacin treatment.

The purposes of this study were to examine the response of the patent ductus arteriosus (PDA) to indomethacin, using serial two-dimensional and pulsed Doppler echocardiographic studies, and to correlate the response to treatment with serum indomethacin levels. Nineteen preterm infants (gestational age, 26 to 31 weeks [mean, 28 weeks]; weight, 600 to 1680 g [mean, 1060 g]) were treated with indomethacin. Two-dimensional and pulsed Doppler echocardiograms were obtained before administration of indomethacin and daily thereafter until the day after the last dose. Ductal responses to treatment were graded as open, constricted, or closed, and serum indomethacin levels were obtained 24 hours after the last dose. The PDA initially closed in 11 (58%) of 19 infants; however, in four of the 11, PDA reopened and three of four required surgical ligation. In seven (37%) of 19 patients, the PDA initially constricted, but five of seven subsequently reopened and required ligation. In one patient, indomethacin had no effect on the PDA. The mean indomethacin level for the whole group was 622 ng/mL. There was no difference in indomethacin level between the group with initial closure vs those with constriction (580 vs 590 ng/mL), nor between those who eventually required ligation and those who did not. This study demonstrates that the majority of premature infants respond to indomethacin treatment with ductal constriction or closure but that reopening occurs frequently. The initial response does not mean that the ductus will remain constricted or closed, and surgical intervention may still be necessary. A serum indomethacin level of more than 250 ng/mL does not ensure ductal closure.

Tetralogy of Fallot with major aortopulmonary collateral arteries.

The clinical features of eight patients with tetralogy of Fallot and major aortopulmonary collateral arteries were determined and found to be usually unhelpful in differentiating such patients from those with pulmonary atresia with ventricular septal defect. The point of connection between the pulmonary and collateral arteries could usually be demonstrated at cineangiography by observing washin and washout between the two systems. The central pulmonary arteries connected with the entire pulmonary vascular bed in the five patients in whom the anatomy of the pulmonary circulation was clearly demonstrated and were thought to do so in the remaining three patients also. In six out of eight patients only one collateral artery connected with each hilar pulmonary artery. These findings suggest that the anatomy of the pulmonary circulation in patients with tetralogy of Fallot and major aortopulmonary collateral arteries is usually less complex than in pulmonary atresia with ventricular septal defect, making the outlook for complete repair more hopeful. The major determinant of successful complete repair appears to be pulmonary arterial size. Early palliative surgery to increase pulmonary blood flow is recommended to encourage normal growth of the central and intrapulmonary arteries.

Right and left ventricular function at rest and with exercise after the Mustard operation for transposition of the great arteries.

Right and left ventricular function was assessed in 25 children (mean age at study 12.2 years and at operation 2.6 years) after a Mustard repair for transposition of the great arteries. Gated first pass and gated equilibrium radionuclide ventriculography was performed on all patients at rest and during supine bicycle exercise. The mean right ventricular ejection fraction did not increase with exercise by either technique. Individual results for right ventricular ejection fraction showed that with the gated equilibrium technique 71% had an abnormal exercise response (normal response being an increase in ejection fraction greater than 5%) and with the gated first pass technique 61% had abnormal results. Although the mean left ventricular ejection fraction increased significantly with exercise, 35% of patients had an abnormal exercise response with the equilibrium technique and 41% with the first pass technique. There was no evidence of a predictive relation between ventricular function and any clinical or haemodynamic variable examined. Covert right and left ventricular dysfunction can frequently be detected by exercise radionuclide ventriculography in long term survivors of repair for transposition of the great arteries. The prognostic consequences of these findings are unclear at present.