Pre-chemotherapy values for left and right ventricular volumes and ejection fraction by gated tomographic radionuclide angiography using a cadmium-zinc-telluride detector gamma camera.

BACKGROUND: Estimation of left ventricular ejection fraction (LVEF) using equilibrium radionuclide angiography is an established method for assessment of left ventricular function. The purpose of this study was to establish normative data on left and right ventricular volumes and ejection fraction, using cadmium-zinc-telluride SPECT camera. METHODS AND RESULTS: From routine assessments of left ventricular function in 1172 patients, we included 463 subjects (194 men and 269 women) without diabetes, previous potentially cardiotoxic chemotherapy, known cardiovascular or pulmonary disease. The lower limits defined as mean value minus two standard deviations for ventricular ejection fraction and end diastolic volume were LVEF (men: 50%, women: 50%), LEDV (men: 45 mL, women: 40 mL), RVEF (men: 29%, women: 28%), and REDV (men: 73 mL, women: 57 mL).There was a significant negative correlation between age and both left and right ventricular volumes in women (r = -0.4, P < .001) but only for right end systolic ventricular volume in men (r = -0.3, P = .001). CONCLUSION: A set of reference values for cardiac evaluation prior to chemotherapy in cancer patients without other known cardiopulmonary disease is presented. There are age-related changes in cardiac dimensions with age depending on gender, although with only limited influence on LVEF or RVEF.

A comparison of immune responses to infection with virulent infectious bursal disease virus (IBDV) between specific-pathogen-free chickens infected at 12 and 28 days of age.

Previous studies indicated that the pathogenesis of infectious bursal disease virus (IBDV) may vary depending on the age of the infected chicken. The reason for this difference is not clear, immunopathogenesis studies comparing different age groups are lacking. In the present study the IBDV-immunopathogenesis was compared in 12-day-old and 28-day-old specific-pathogen-free layer-type chickens. Birds were inoculated with the classic virulent strain IBDV-IM. Interestingly, the up-regulation of interferon (IFN)-gamma and interleukin-1beta expression varied between the two IBDV-infected age groups. The cytokine expression pattern was different between IBDV-infected age groups in magnitude and timing not only in bursal tissue and caecal tonsils but also in the spleen. No variations between the different age groups were observed in IBDV-induced bursa lesions, accumulation of intrabursal T cells and macrophages, and systemic stimulation of the release of nitric oxide inducing factors. Furthermore, virus-neutralizing antibody levels were comparable between age groups. Under these experimental conditions, age-related differences were found only for the cytokine patterns but interestingly this did not influence the outcome of the disease with IBDV-IM.

Bilateral effects of vaccination against infectious bursal disease and Newcastle disease in specific-pathogen-free layers and commercial broiler chickens.

Different infectious bursal disease virus (IBDV) live vaccines (intermediate, intermediate plus) were compared for their immunosuppressive abilities in specific-pathogen-free (SPF) layer-type chickens or commercial broilers. The Newcastle disease virus (NDV) vaccination model was applied to determine not only IBDV-induced immunosuppression but also bilateral effects between IBDV and NDV. None of the IBDV vaccines abrogated NDV vaccine-induced protection. All NDV-vaccinated SPF layers and broilers were protected against NDV challenge independent of circulating NDV antibody levels. Sustained suppression of NDV antibody development was observed in SPF layers, which had received the intermediate plus IBDV vaccine. We observed a temporary suppression of NDV antibody development in broilers vaccinated with one of the intermediate, as well as the intermediate plus, IBDV vaccines. Different genetic backgrounds, ages, and residual maternal antibodies might have influenced the pathogenesis of IBDV in the different types of chickens. Temporary suppression of NDV antibody response in broilers was only seen if the NDV vaccine was administered before and not, as it was speculated previously, at the time the peak of IBDV-induced bursa lesions was detected. For the first time, we have demonstrated that the NDV vaccine had an interfering effect with the pathogenesis of the intermediate as well as the intermediate plus IBDV vaccine. NDV vaccination enhanced the incidence of IBDV bursa lesions and IBDV antibody development. This observation indicates that this bilateral effect of an IBDV and NDV vaccination should be considered in the field and could have consequences for the performance of broiler flocks.

Differences in the immunopathogenesis of infectious bursal disease virus (IBDV) following in ovo and post-hatch vaccination of chickens.

Not much is known about IBDV-pathogenesis and immune mechanisms following in ovo vaccination. In this study, we compared the immunopathogenesis of an intermediate IBDV-vaccine in post-hatch- and in ovo-inoculated chickens. In ovo-vaccinated birds recovered significantly faster from lesions of the bursa of Fabricius than post-hatch vaccinated (P<0.05). A significant accumulation of intrabursal CD8(+) T cells was observed in post-hatch but not in in ovo-vaccinated chickens (P<0.05). The innate immunity was comparable between in ovo- and post-hatch-vaccinated groups as indicated by comparable intrabursal macrophage accumulation and intrabursal IBDV-clearance. Overall, our observations indicate that IBDV in ovo vaccination may be advantageous over post-hatch. In ovo-vaccinated birds recover faster from bursa lesions and exhibit similar protection against challenge in comparison to post-hatch vaccinated.

Interstudy repeatability of left and right ventricular volume estimations by serial-gated tomographic radionuclide angiographies using a cadmium-zinc-telluride detector gamma camera.

PURPOSE: Estimation of left ventricular ejection fraction (LVEF) with 99MTc-HSA equilibrium radionuclide angiography (RA) is frequently used for assessing cardiac function. The purpose of this study was to investigate the interstudy repeatability of left (LV) and right (RV) ventricular volume and ejection fraction estimations, using a cadmium-zinc-telluride (CZT) SPECT camera. MATERIALS AND METHODS: Forty-six patients were scanned twice, interrupted by repositioning. Each acquisition was analysed twice by two experienced technologists. Interstudy and interobserver variations were calculated as the coefficient of variation (CV) and the 95% confidence interval (CI) for limits of agreement (LOA) between each sequence of analyses for each of the two acquisitions. RESULTS: The Interstudy variations and 95% CI for LVEF, LV end systolic (LVESV) and end diastolic (LVEDV) volumes were 4.6% (-5.4 to 6.4), 9.3% (-6.90 to 5.20) and 7.0% (-13.9 to 11.1), respectively. For the right ventricle, the corresponding values were 11.9% (-9.40 to 10.8), 9.8% (-14.9 to 10.8) and 8.1% (-20.7 to 16.3). DISCUSSION: The CZT detector camera has excellent reproducibility with regard to interstudy variation when assessing LV volumes and EF. Interstudy variation is considerably higher for RV volumes and EF, indicating a lack of consistency in tracing the boarders of the right ventricle.

Age- and sex-dependent reference intervals for D-dimer: evidence for a marked increase by age.

INTRODUCTION: A low D-dimer is commonly used to exclude venous thromboembolism in low risk patients. However, the reference intervals are poorly defined and D-dimer has been shown to increase by patient age. We aimed to establish age- and sex-dependent D-dimer reference intervals and to test the consequence of different cut-off limits. MATERIALS AND METHODS: By means of the STA-Lia test D-dimer was measured in 1,352 subjects aged between 23 and 93years from the general population. A further 94 subjects were measured with the HemosIL test. RESULTS: The reference intervals were age-dependent with the upper 95% limit increasing from 0.92 FEU mg/L in the age group <50years to 2.39 FEU mg/L in the group ≥70years. Minor differences in the reference intervals between sexes were found. The commonly used cut-off at 0.5 FEU mg/L resulted in a decrease of negatives from 91% in <50years to 56 % in ≥70years. The age-dependent cut-off value (patient's age*0.01 FEU mg/L in 50+ years) resulted in an increase of negatives by age. The linear increase in D-dimer has a slope at approximately 0.0077*age, meaning that a cut-off at (patient's age*0.0077) FEU mg/L, gives an almost constant number of positives across age groups. The two assays showed a poor correlation and a higher percentage of positives using the STA Lia test. CONCLUSIONS: The age-dependent increase in D-dimer seen in patients was confirmed, which questions the clinical value of the present cut-off for venous thromboembolism.

Local and systemic immune responses following infection of broiler-type chickens with avian Metapneumovirus subtypes A and B.

Infections with avian Metapneumovirus (aMPV) are often associated with swollen head syndrome in meat type chickens. Previous studies in turkeys have demonstrated that local humoral and cell-mediated immunity plays a role in aMPV-infection. Previous experimental and field observations indicated that the susceptibility of broilers and their immune reactions to aMPV may differ from turkeys. In the presented study local and systemic immune reactions of broilers were investigated after experimental infections with subtypes A and B aMPV of turkey origin. Both virus subtypes induced a mild respiratory disease. The recovery from respiratory signs correlated with the induction of local and systemic aMPV virus-neutralizing antibodies, which began to rise at 6 days post infection (dpi), when the peak of clinical signs was observed. In a different manner to the virus neutralizing (VN) and IgG-ELISA serum antibody titres, which showed high levels until the end of the experiments between 24 and 28 dpi, the specific IgA-ELISA and VN-antibody levels in tracheal washes decreased by 10 and 14 dpi, respectively, which may explain the recurring aMPV-infections in the field. Ex vivo cultured spleen cells from aMPV-infected broilers released at 3 and 6 dpi higher levels of IFN-γ after stimulation with Concanavalin A as compared to virus-free birds. In agreement with studies in turkeys, aMPV-infected broilers showed a clear CD4+ T cell accumulation in the Harderian gland (HG) at 6 dpi (P<0.05). In contrast to other investigations in turkeys aMPV-infected broilers showed an increase in the number of CD8alpha+ cells at 6 dpi compared to virus-free birds (P<0.05). The numbers of local B cells in the Harderian gland were not affected by the infection. Both aMPV A and B induced up-regulation of interferon (IFN)-γ mRNA-expression in the nasal turbinates, while in the Harderian gland only aMPV-A induced enhanced IFN-γ expression at 3 dpi. The differences in systemic and local T cell and possibly natural killer cell activity in the HG between turkeys and chickens may explain the differences in aMPV-pathogenesis between these two species.