Vitamin K supplementation and arterial calcification in dialysis: results of the double-blind, randomized, placebo-controlled RenaKvit trial

Background

Arterial calcification is associated with cardiovascular mortality in dialysis patients. Active matrix Gla protein (MGP) is a vitamin K-dependent inhibitor of arterial calcification. Elevated plasma concentrations of inactive MGP, i.e. dephosphorylated-uncarboxylated MGP (dp-ucMGP), are prevalent in dialysis patients. MGP inactivity might contribute to arterial calcification. We investigated whether vitamin K supplementation had an effect on arterial calcification in chronic dialysis patients.

Methods

In a 2-year, double-blind, placebo-controlled intervention trial, 48 dialysis patients were randomized to vitamin K [menaquinone-7 (MK-7), 360 µg daily] or placebo. MK-7 in serum and dp-ucMGP in plasma were used to assess vitamin K status. Carotid-femoral pulse wave velocity (cfPWV) and scores of coronary arterial calcification (CAC) and abdominal aortic calcification (AAC) were used to assess arterial calcification.

Results

Thirty-seven participants completed Year 1, and 21 completed Year 2. At Year 2, serum MK-7 was 40-fold higher, and plasma dp-ucMGP 40% lower after vitamin K supplementation compared with placebo {mean dp-ucMGP difference: −1380 pmol/L [95% confidence interval (CI) −2029 to −730]}. There was no significant effect of vitamin K supplementation on cfPWV [mean difference at Year 2: 1.2 m/s (95% CI −0.1 to 2.4)]. CAC Agatston score increased significantly in vitamin K supplemented participants, but was not significantly different from placebo [mean difference at Year 2: 664 (95% CI −554 to 1881)]. AAC scores increased in both groups, significantly so within the placebo group at Year 1, but with no significant between-group differences.

Conclusions

Vitamin K supplementation improved vitamin K status, but did not hinder or modify the progression of arterial calcification in dialysis patients.

Immunocompetence and resistance to marble spleen disease of broiler- and layer-type pure lines of chickens

The intent of this study was to evaluate, under concurrent conditions, certain responses that may be important in chicken breeding and growing. Three commercial broiler pure lines (A, B, and C) and two experimental White Leghorn lines selected for high (HAS) and low (LAS) antibody response to sheep red blood cells were evaluated concurrently for humoral and cell-mediated immunocompetence, resistance to marble spleen disease virus (MSDV), relative asymmetry (RA), and comb weight. Chicks were injected with 0.1 ml of 0.25% SRBC at 21 days of age. Antibody response 6 days after injection was highest in line HAS. Titres for the commercial lines were similar to those in line LAS. The cutaneous basophil hypersensitivity test, an in vivo cell-mediated immune response, was measured as the increase in toe-web thickness 24 h after an injection with T-cell mitogen phytohaemagglutinin (PHA)-P or -M into a sample of chicks at 9 days of age and a different sample of chicks at 20 days of age. PHA-P elicited greater responses than PHA-M at both ages. The pattern among stocks, however, differed depending upon age. Responses at 9 days were greater for the Leghorn than broiler lines, while at 20 days, responses were greater in lines A and LAS than in lines B, C, and HAS. Resistance to MSDV challenge differed among stocks, with the ranking for resistance being C>(A=B=LAS)>HAS. Rankings of RA for normal thickness of the toe web between the third and fourth digits at 9 days of age were (HAS=LAS)>(A=B=C). There were no differences in RA among stocks at 20 days of age. There was a significant line by sex interaction for relative comb weight, due to differences between lines for males but not females. Data from this study suggest that competence in one arm of the immune system is not a reliable measure of general immunocompetence, nor is it a measure of resistance in general.

Risk of thromboembolism and fatal stroke in patients with psoriasis and nonvalvular atrial fibrillation: a Danish nationwide cohort study

OBJECTIVES

Psoriasis is a chronic inflammatory disease that is associated with a prothrombotic state and cardiovascular disease, including atrial fibrillation and thromboembolism. We therefore evaluated the impact of psoriasis in patients with atrial fibrillation and the performance of the CHA2 DS2 VASc score in these patients.

DESIGN, SETTING AND PARTICIPANTS

The study comprised all Danish patients hospitalized with nonvalvular atrial fibrillation in the period 1997-2011 (n = 99,357). Follow-up started 7 days from discharge and excluded subjects treated with anticoagulation. Poisson regression adjusted for CHA2 DS2 VASc score was used to estimate the incidence rate ratios and 95% confidence intervals.

MAIN OUTCOME MEASURE

Hospitalization or death from thromboembolism.

RESULTS

Mean follow-up was 3.5, 3.1, and 2.8 years for patients with no psoriasis, mild psoriasis and severe psoriasis, respectively. Patients with psoriasis were younger compared to patients without psoriasis, but CHA2DS2VASc score did not differ between the three groups. Thromboembolism rates per 100 patient-years (95% confidence intervals) were 4.8 (4.7-4.9), 4.8 (4.2-5.4) and 6.1 (5.0-7.5) for patients with no psoriasis, mild psoriasis and severe psoriasis, respectively. Importantly, the observed thromboembolism rates in patients with severe psoriasis were markedly higher (2.6- to3.4-fold) than predicted by the CHA2 DS2 VASc score. Relative to no psoriasis, incidence rate ratios were 0.99 (0.87-1.11) and 1.27 (1.02-1.57) for mild and severe psoriasis, respectively. Correspondingly, incidence rate ratios for fatal stroke were 0.97 (0.80-1.12) and 1.51 (1.12-2.05).

CONCLUSIONS

In patients with nonvalvular atrial fibrillation not treated with oral anticoagulation, severe psoriasis was associated with increased risk of thromboembolism. In these patients, CHA2 DS2 VASc underestimated the risk of thromboembolism.

[Extravasation of contrast following coronary angiography can be misinterpretated as subarachnoid haemorrhage]

Brain parenchymal extravasation of contrast has been described after infusion of larger amounts of iodinated X-ray contrast agent. We describe a case in which a patient after infusion of 500 ml iomeprole 350 mg/ml developed neurological symptoms and a subsequent cerebral computed tomography (CT) scan was interpreted as subarachnoid haemorrhage. The patient was fully recovered within 48 hours, and a follow-up CT scan 26 hours later showed no signs of haemorrhage. In patients with sudden onset of neurological symptoms after infusion of large quantities of contrast media and a CT scan showing signs of subarachnoid haemorrhage, spinal puncture or magnetic resonance imaging should be considered prior to interventional procedures in order to verify the diagnosis.

Once versus twice daily gentamicin dosing for infective endocarditis: a randomized clinical trial

OBJECTIVES

The aim of this randomized study was to investigate the effects of once versus twice daily gentamicin dosing on renal function and measures of infectious disease in a population with infective endocarditis (IE).

METHODS

Seventy-one IE patients needing gentamicin treatment according to guidelines were randomized to either once (n = 37) or twice daily (n = 34) doses of gentamicin. Kidney function (glomerular filtration rate, GFR) was measured with an isotope method ((51)Cr-EDTA) at the beginning of treatment and at discharge. Treatment efficacy was assessed by C-reactive protein (CRP) time to half-life, mean CRP and leukocytes.

RESULTS

Baseline GFR was similar in the two groups. Both groups displayed a significant fall in GFR from admission to discharge. The mean decrease in GFR was as follows: with once daily gentamicin, 17.0% (95% confidence interval 7.5-26.5), and with twice daily gentamicin, 20.4% (95% confidence interval 12.0-28.8). However, there was no significant difference in the GFR decrease between the once and twice daily regimens (p = 0.573). No difference in infection parameters was demonstrated between the two dosing regimens.

CONCLUSIONS

A twice daily gentamicin dosing regimen is neither less nephrotoxic nor more efficient than a once daily regimen in the treatment of IE patients. When indicated, gentamicin may therefore also be administered as a single-dose regimen in the treatment of IE patients.

Persistent infection of turkeys with an avirulent strain of turkey hemorrhagic enteritis virus

The Virginia avirulent strain (VAS) of turkey hemorrhagic enteritis virus (THEV), which is commonly used in live vaccines for commercial turkeys, was studied to determine characteristics of infection. It has been observed that turkeys infected with the VAS maintain protective antibody levels in excess of 20 wk postvaccination. It is theorized that this immune response is modulated by either a persistent or latent infection. A series of studies have been undertaken to determine changes in virus location and serology over time. A trial was also conducted to evaluate the effect of corticosteroid administration on viral recrudescence, and an attempt was made to isolate live virus from tissues of birds 10 wk postinfection (pi). Antibody titers were determined by enzyme-linked immunosorbent assay, and PCR was used to detect viral DNA. Histopathology was performed on formalin-fixed paraffinized tissues. Viral DNA was detected in various tissues through 15 wk pi in the presence of high antibody titers. Viral DNA was detected at 3-5 days pi in the spleens of susceptible turkeys inoculated with tissues collected from infected birds at 10 wk pi. It is unknown whether the viral DNA is associated with live virus or rather is the result of persistent maintenance of the viral genome within lymphoid/macrophage target cells. Future studies will test for viral RNA in order to confirm the presence of replicating THEV. Regardless of the actual status of the THEV DNA detected at 10-15 wk pi, it is clear that THEV does not cause a simple acute infection. The characteristics of THEV infection are identical to the nonlytic persistent infections seen in human adenoviruses, and therefore THEV may serve as a model for the study of virus-cell interactions mediating persistence.

Functional effects of KCNE3 mutation and its role in the development of Brugada syndrome

INTRODUCTION

The Brugada Syndrome (BrS), an inherited syndrome associated with a high incidence of sudden cardiac arrest, has been linked to mutations in four different genes leading to a loss of function in sodium and calcium channel activity. Although the transient outward current (I(to)) is thought to play a prominent role in the expression of the syndrome, mutations in I(to)-related genes have not been identified as yet.

METHODS AND RESULTS

One hundred and five probands with BrS were screened for ion channel gene mutations using single strand conformation polymorphism (SSCP) electrophoresis and direct sequencing. A missense mutation (R99H) in KCNE3 (MiRP2) was detected in one proband. The R99H mutation was found 4/4 phenotype positive and 0/3 phenotype-negative family members. Chinese hamster ovary (CHO)-K1 cells were co-transfected using wild-type (WT) or mutant KCNE3 and either WT KCND3 or KCNQ1. Whole-cell patch clamp studies were performed after 48 hours. Interactions between Kv4.3 and KCNE3 were analyzed in co-immunoprecipitation experiments in human atrial samples. Co-transfection of R99H-KCNE3 with KCNQ1 produced no alteration in current magnitude or kinetics. However, co-transfection of R99H KCNE3 with KCND3 resulted in a significant increase in the I(to) intensity compared to WT KCNE3+KCND3. Using tissues isolated from left atrial appendages of human hearts, we also demonstrate that K(v)4.3 and KCNE3 can be co-immunoprecipitated.

CONCLUSIONS

These results provide definitive evidence for a functional role of KCNE3 in the modulation of I(to) in the human heart and suggest that mutations in KCNE3 can underlie the development of BrS.

Increased urinary orosomucoid excretion: a proposed marker for inflammation and endothelial dysfunction in patients with type 2 diabetes

OBJECTIVE

In a previous study, urinary orosomucoid excretion rate (UOER) independently predicted cardiovascular mortality in patients with type 2 diabetes. The aim of the present study was to determine whether increased UOER is associated with cardiovascular risk factors such as inflammation, impaired left ventricular function and endothelial dysfunction in patients with type 2 diabetes.

MATERIAL AND METHODS

We performed a cross-sectional study of 41 patients with type 2 diabetes (17 patients with normal UOER and 24 with increased UOER) with no history of cardiovascular disease and 21 healthy controls. Urinary orosomucoid was measured using a particle-enhanced immunoturbidimetric assay. Plasma interleukin-6 (IL-6), tissue plasminogen activator (tPA) and soluble intercellular adhesion molecule-1 (sICAM) were measured using ELISA. Endothelial function measured as vasodilatory capacity of the brachial artery and echocardiography were done in all participants.

RESULTS

Patients with diabetes and increased UOER had subclinically increased serum orosomucoid (p<0.001), C-reactive protein (CRP) (p<0.001), IL-6 (p<0.001), tPA (p<0.003) and sICAM (p<0.003) compared with healthy controls. In patients with type 2 diabetes, UOER was independently associated with increasing values of IL-6 (1.43 (1.06-1.93)) and tPA (1.82 (1.20-2.77)). Measurements by echocardiography showed no signs of cardiac dysfunction.

CONCLUSIONS

Asymptomatic patients with type 2 diabetes and increased UOER displayed signs of chronic low-grade inflammation and endothelial dysfunction. UOER was independently related to markers of proinflammation and endothelial dysfunction in patients with type 2 diabetes. The previously shown relation between increased UOER and cardiovascular mortality is proposed to be caused by chronic low-grade inflammation and early endothelial dysfunction.

The ischemic electrocardiogram: A harbinger for ischemic heart disease independent of the blood pressure level. The Copenhagen City Heart Study

Information is limited on the co-existence and prognostic association of the ischemic electrocardiogram (ECG) and blood pressure. Prospectively collected data sets from 28,118 examinations in the Copenhagen City Heart Study were analyzed for cardiac morbidity and mortality for a 5.9-year follow-up. The prognosis of the ECG, independently of blood pressure, was examined. The Cox proportional hazard model was employed to evaluate the prognostic implications of ECG findings and relative risk was adjusted for age and multivariately adjusted for traditional cardiovascular risk factors. End-points were (1) fatal and non-fatal ischemic heart disease (IHD) events and (2) cardiovascular disease (CVD) mortality. During a total follow-up period of 166,471 person years (mean: 5.9 years) 1.481 IHD events were recorded and 1.051 CVD deaths. The relative risk of an ischemic ECG was independent of the blood pressure level. The multivariately adjusted relative risk for fatal and non-fatal IHD for the ischemic ECG was 1.70 (95% CI: 1.39-2.09, p < 0.001) in women, and 1.96 (95% CI: 1.67-2.30, p < 0.001) in men, and for CVD mortality 1.71 (95% CI: 1.34-2.17, p < 0.001) in women and 2.08 (95% CI: 1.74-2.49, p < 0.001) in men. An ECG with left ventricular hypertrophy (LVH) and ST-depression was the finding with the highest risk for future events. LVH by ECG voltage-only was associated with no statistically increased risk, except for men treated for arterial hypertension.

Generation and infectivity titration of an infectious stock of avian hepatitis E virus (HEV) in chickens and cross-species infection of turkeys with avian HEV

Avian hepatitis E virus (HEV), a novel virus identified from chickens with hepatitis-splenomegaly syndrome in the United States, is genetically and antigenically related to human HEV. In order to further characterize avian HEV, an infectious viral stock with a known infectious titer must be generated, as HEV cannot be propagated in vitro. Bile and feces collected from specific-pathogen-free (SPF) chickens experimentally infected with avian HEV were used to prepare an avian HEV infectious stock as a 10% suspension of positive fecal and bile samples in phosphate-buffered saline. The infectivity titer of this infectious stock was determined by inoculating 1-week-old SPF chickens intravenously with 200 microl of each of serial 10-fold dilutions (10(-2) to 10(-6)) of the avian HEV stock (two chickens were inoculated with each dilution). All chickens inoculated with the 10(-2) to 10(-4) dilutions of the infectious stock and one of the two chickens inoculated with the 10(-5) dilution, but neither of the chickens inoculated with the 10(-6) dilution, became seropositive for anti-avian HEV antibody at 4 weeks postinoculation (wpi). Two serologically negative contact control chickens housed together with chickens inoculated with the 10(-2) dilution also seroconverted at 8 wpi. Viremia and shedding of virus in feces were variable in chickens inoculated with the 10(-2) to 10(-5) dilutions but were not detectable in those inoculated with the 10(-6) dilution. The infectivity titer of the infectious avian HEV stock was determined to be 5 x 10(5) 50% chicken infectious doses (CID(50)) per ml. Eight 1-week-old turkeys were intravenously inoculated with 10(5) CID(50) of avian HEV, and another group of nine turkeys were not inoculated and were used as controls. The inoculated turkeys seroconverted at 4 to 8 wpi. In the inoculated turkeys, viremia was detected at 2 to 6 wpi and shedding of virus in feces was detected at 4 to 7 wpi. A serologically negative contact control turkey housed together with the inoculated ones also became infected through direct contact. This is the first demonstration of cross-species infection by avian HEV.

Genetic identification of avian hepatitis E virus (HEV) from healthy chicken flocks and characterization of the capsid gene of 14 avian HEV isolates from chickens with hepatitis–splenomegaly syndrome in different geographical regions of the United States

Avian hepatitis E virus (HEV), a novel virus identified from chickens with hepatitis-splenomegaly (HS) syndrome, is genetically and antigenically related to human HEV. Recently, it was found that avian HEV antibody is also prevalent in healthy chickens. A prospective study was done on a known seropositive but healthy chicken farm to identify avian HEV isolates from healthy chickens. Fourteen chickens were randomly selected, tagged and monitored under natural conditions for 19 weeks. All 14 chickens were seronegative at the beginning of the study at 12 weeks of age. By 21 weeks of age, all 14 chickens had seroconverted to avian HEV antibody. None of the chickens had any sign of HS syndrome. Partial helicase gene and capsid gene sequences of avian HEV isolates recovered from a healthy chicken were determined and found to share 75-97 % nucleotide sequence identity with the corresponding regions of avian HEV isolates from chickens with HS syndrome. Thus far, only one strain of avian HEV from a chicken with HS syndrome has been genetically characterized for its capsid gene, therefore the capsid gene region of an additional 14 isolates from chickens with HS syndrome were also characterized. The capsid genes of avian HEV isolates from chickens with HS syndrome were found to be heterogeneic, sharing 76-100 % nucleotide sequence identity with each other. This study indicates that avian HEV is enzootic in chicken flocks and spreads subclinically among chickens in the United States and that the virus is heterogeneic.

Comparison of sampling techniques for detection of Arcobacter butzleri from chickens

Arcobacter butzleri is a causative agent of human enteritis that has been recently differentiated from the genus Campylobacter. Previous work suggests that its transmission to humans is likely through a foodborne route with a substantial tendency to be located on poultry carcasses. For reducing the incidence of this pathogen on commercial poultry, improved protocols are needed to sample and identify A. butzleri from infected birds prior to slaughter. The purpose of this study was to compare sampling methods for this emerging pathogen from chickens that were artificially inoculated per os with A. butzleri. We tested three sampling techniques commonly used to determine the microbiological quality of poultry: cloacal swabs, fecal samples, and environmental surface (drag) swabs collected when birds were 3, 5, or 7 wk old. These samples were cultured in Johnson-Murano enrichment broth and analyzed by PCR. Results indicate that environmental surface swabs yielded the highest recovery percentage. A detection rate of 75 to 100% was observed for each sampling period (age of chicken). Additionally, A. butzleri could not be isolated from the intestinal tract (jejunum, ileum, cecum, colorectum) of inoculated birds.

Heterogeneity and seroprevalence of a newly identified avian hepatitis e virus from chickens in the United States

We recently identified and characterized a novel virus, designated avian hepatitis E virus (avian HEV), from chickens with hepatitis-splenomegaly syndrome (HS syndrome) in the United States. Avian HEV is genetically related to but distinct from human and swine HEVs. To determine the extent of genetic variation and the seroprevalence of avian HEV infection in chicken flocks, we genetically identified and characterized 11 additional avian HEV isolates from chickens with HS syndrome and assessed the prevalence of avian HEV antibodies from a total of 1,276 chickens of different ages and breeds from 76 different flocks in five states (California, Colorado, Connecticut, Virginia, and Wisconsin). An enzyme-linked immunosorbent assay using a truncated recombinant avian HEV ORF2 antigen was developed and used to determine avian HEV seroprevalence. About 71% of chicken flocks and 30% of chickens tested in the study were positive for antibodies to avian HEV. About 17% of chickens younger than 18 weeks were seropositive, whereas about 36% of adult chickens were seropositive. By using a reverse transcription-PCR (RT-PCR) assay, we tested 21 bile samples from chickens with HS syndrome in California, Connecticut, New York, and Wisconsin for the presence of avian HEV RNA. Of the 21 bile samples, 12 were positive for 30- to 35-nm HEV-like virus particles by electron microscopy (EM). A total of 11 of the 12 EM-positive bile samples and 6 of the 9 EM-negative bile samples were positive for avian HEV RNA by RT-PCR. The sequences of a 372-bp region within the helicase gene of 11 avian HEV isolates were determined. Sequence analyses revealed that the 11 field isolates of avian HEV had 78 to 100% nucleotide sequence identities to each other, 79 to 88% identities to the prototype avian HEV, 76 to 80% identities to chicken big liver and spleen disease virus, and 56 to 61% identities to other known strains of human and swine HEV. The data from this study indicated that, like swine and human HEVs, avian HEV isolates are genetically heterogenic and that avian HEV infection is enzoonotic in chicken flocks in the United States.

The putative capsid protein of the newly identified avian hepatitis E virus shares antigenic epitopes with that of swine and human hepatitis E viruses and chicken big liver and spleen disease virus

We recently identified a novel virus, designated avian hepatitis E virus (avian HEV), from chickens with hepatitis-splenomegaly (HS) syndrome in the USA. We showed that avian HEV is genetically related to swine and human HEVs. Here we report the antigenic cross-reactivity of the putative open reading frame 2 (ORF2) capsid protein of avian HEV with those of swine and human HEVs and the Australian chicken big liver and spleen disease virus (BLSV). The region encoding the C-terminal 268 amino acid residues of avian HEV ORF2 was cloned into expression vector pRSET-C. The truncated ORF2 protein was expressed in E. coli as a fusion protein and purified by affinity chromatography. Western blot analysis revealed that the avian HEV ORF2 protein reacted with antisera against the Sar-55 strain of human HEV and with convalescent antisera against swine HEV and the US2 strain of human HEV, as well as with antiserum against BLSV. Convalescent sera from specific-pathogen-free chickens experimentally infected with avian HEV also reacted with the recombinant capsid proteins of swine HEV and Sar-55 human HEV. Antisera against the US2 human HEV also reacted with recombinant ORF2 proteins of both swine HEV and Sar-55 human HEV. The antigenic cross-reactivity of the avian HEV putative capsid protein with those of swine and human HEVs was further confirmed, for the most part, by ELISA assays. The data indicate that avian HEV shares certain antigenic epitopes in its putative capsid protein with swine and human HEVs, as well as with BLSV. The results have implications for HEV diagnosis and taxonomy.

Prevalence and prognosis of electrocardiographic left ventricular hypertrophy, ST segment depression and negative T-wave; the Copenhagen City Heart Study

AIMS

To evaluate the prevalence and the independent prognosis of electrocardiographic left ventricular hypertrophy by voltage only, ST depression and negative T wave, isolated negative T wave and left ventricular hypertrophy plus ST depression and negative T wave for cardiac morbidity and mortality, without known ischaemic heart disease at baseline.

METHODS AND RESULTS

Follow-up data from the Copenhagen City Heart Study were used. Subjects were 5243 men and 6391 women, age range 25-74 years. End-points were (1) myocardial infarction, (2) ischaemic heart disease and (3) cardiovascular disease mortality. Relative risk was age- and sex-adjusted, and multivariately adjusted for known cardiovascular risk factors. During 7 years follow-up, left ventricular hypertrophy plus ST depression and negative T wave had an age-adjusted relative risk of 3.78 (95% confidence interval 2.29-6.25) for myocardial infarction, 4.27 (2.95-6.16) for ischaemic heart disease and 3.75 (2.41-5.85) for cardiovascular disease. A negative T wave, ST depression and negative T wave changes, and left ventricular hypertrophy with negative T wave also carry independent prognostic information for myocardial infarction, ischaemic heart disease and cardiovascular disease.

CONCLUSIONS

Electrocardiographic left ventricular hypertrophy with ST depression and negative T wave changes are the electrocardiographic abnormalities with the greatest prognostic information for future cardiac events. Electrocardiographic negative T waves, ST depression and negative T wave abnormalities and left ventricular hypertrophy with negative T waves, also have prognostic information.

Cross sectional study estimating prevalence of heart failure and left ventricular systolic dysfunction in community patients at risk

OBJECTIVE

To examine a general practice population to measure the prevalence of signs and symptoms of heart failure (SSHF) and left ventricular systolic dysfunction (LVSD).

DESIGN

Cross sectional screening study in three general practices followed by echocardiography.

SETTING AND PATIENTS

All patients ⩾ 50 years in two general practices and ⩾ 40 years in one general practice were screened by case record reviews and questionnaires (n = 2158), to identify subjects with some evidence of heart disease. Among these, subjects were sought who had SSHF (n = 115). Of 357 subjects with evidence of heart disease, 252 were eligible for examination, and 126 underwent further cardiological assessment, including 43 with SSHF.

MAIN OUTCOME MEASURES

Prevalence of SSHF as defined by a modified Boston index, LVSD defined as an indirectly measured left ventricular ejection fraction ⩽ 0.45, and numbers of subjects needing an echocardiogram to detect one case with LVSD.

RESULTS

SSHF afflicted 0.5% of quadragenarians and rose to 11.7% of octogenarians. Two thirds were handled in primary care only. At ⩾ 50 years of age 6.4% had SSHF, 2.9% had LVSD, and 1.9% (95% confidence interval 1.3% to 2.5%) had both. To detect one case with LVSD in primary care, 14 patients with evidence of heart disease without SSHF and 5.5 patients with SSHF had to be examined.

CONCLUSION

SSHF is extremely prevalent in the community, especially in primary care, but more than two thirds do not have LVSD. The number of subjects with some evidence of heart disease needing an echocardiogram to detect one case of LVSD is 14.

Cross sectional study estimating prevalence of heart failure and left ventricular systolic dysfunction in community patients at risk

OBJECTIVE

To examine a general practice population to measure the prevalence of signs and symptoms of heart failure (SSHF) and left ventricular systolic dysfunction (LVSD).

DESIGN

Cross sectional screening study in three general practices followed by echocardiography.

SETTING AND PATIENTS

All patients >/= 50 years in two general practices and >/= 40 years in one general practice were screened by case record reviews and questionnaires (n = 2158), to identify subjects with some evidence of heart disease. Among these, subjects were sought who had SSHF (n = 115). Of 357 subjects with evidence of heart disease, 252 were eligible for examination, and 126 underwent further cardiological assessment, including 43 with SSHF.

MAIN OUTCOME MEASURES

Prevalence of SSHF as defined by a modified Boston index, LVSD defined as an indirectly measured left ventricular ejection fraction </= 0.45, and numbers of subjects needing an echocardiogram to detect one case with LVSD.

RESULTS

SSHF afflicted 0.5% of quadragenarians and rose to 11.7% of octogenarians. Two thirds were handled in primary care only. At >/= 50 years of age 6.4% had SSHF, 2.9% had LVSD, and 1.9% (95% confidence interval 1.3% to 2.5%) had both. To detect one case with LVSD in primary care, 14 patients with evidence of heart disease without SSHF and 5.5 patients with SSHF had to be examined.

CONCLUSION

SSHF is extremely prevalent in the community, especially in primary care, but more than two thirds do not have LVSD. The number of subjects with some evidence of heart disease needing an echocardiogram to detect one case of LVSD is 14.

Epizootiology of chronic wasting disease in free-ranging cervids in Colorado and Wyoming

Surveillance and epidemic modeling were used to study chronic wasting disease (CWD), a transmissible spongiform encephalopathy that occurs naturally among sympatric, free-ranging deer (Odocoileus spp.) and Rocky Mountain elk (Cervus elaphus nelsoni) populations in contiguous portions of northeastern Colorado and southeastern Wyoming (USA). We used clinical case submissions to identify endemic areas, then used immunohistochemistry to detect CWD-infected individuals among 5,513 deer and elk sampled via geographically-focused random surveys. Estimated overall prevalence (prevalence, 95% confidence interval) in mule deer (4.9%, 4.1 to 5.7%) was higher than in white-tailed deer (2.1%, 0.5 to 3.4%) or elk (0.5%, 0.001 to 1%) in endemic areas; CWD was not detected in outlying portions of either state. Within species, CWD prevalence varied widely among biologically- or geographically-segregated subpopulations within the 38,137 km2 endemic area but appeared stable over a 3-yr period. The number of clinical CWD cases submitted from an area was a poor predictor of local CWD prevalence, and prevalence was typically > or =1% before clinical cases were first detected in most areas. Under plausible transmission assumptions that mimicked field data, prevalence in epidemic models reached about 1% in 15 to 20 yr and about 15% in 37 to 50 yr. Models forecast population declines once prevalence exceeded about 5%. Both field and model data supported the importance of lateral transmission in CWD dynamics. Based on prevalence, spatial distribution, and modeling, we suggest CWD has been occurring in northeastern Colorado and southeastern Wyoming for >30 yr, and may be best represented as an epizootic with a protracted time-scale.

Blood pressure level and relation to other cardiovascular risk factors in male hypertensive patients without clinical evidence of ischemic heart disease

Arterial hypertension is accompanied by increased morbidity and mortality and constitutes a substantial part of medical care. Antihypertensive intervention reduces the cardiovascular morbidity and mortality. The aims of the study were to evaluate the relationship between cardiovascular risk factors and the blood pressure (BP), and to evaluate the percentage of patients who had achieved a BP level as recommended by the sixth report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI). BP was evaluated in relation to age, body mass index, duration of hypertension, cholesterol and triglyceride level, smoking status, information of regular exercise, a family history of ischemic heart disease (IHD) and drug treatment, in 220 men treated for arterial hypertension. In the univariate analyses we found a higher systolic blood pressure (SBP) with older age, higher SBP in smoking patients and lower SBP in patients with regular exercise. In a multivariate model age (p = 0.0004), smoking status (p = 0.01) and regular exercise (p= 0.06) were independently associated with SBP. There was a lower diastolic blood pressure (DBP) with older age, and age was independently associated with DBP. Office SBP was above 140 mmHg in 83% and above 160 mmHg in 44% of patients. During ambulatory blood pressure monitoring (AMBP), SBP was above 135 mmHg in 40% and above 155 mmHg in 15% of patients. In addition to male sex and hypertension there was a high percentage of other cardiovascular risk factors--43% was smoking, 21% had a family history of IHD, 77% had a se-cholesterol above 5.5 mmol/l and 48% had a se-triglyceride above 1.6 mmol/l. In a consecutive group of asymptomatic male treated hypertensive patients SBP is independently associated with age and smoking status, and DBP with age. A high percentage of the patients do not have a well controlled BP, and a high percentage have additional risk factors such as smoking, hypercholesterolaemia, hypertriglyceridaemia and a family history of IHD. This means that there is room for much improvement in the control of hypertension.

Immune competence of chicks from two lines divergently selected for antibody response to sheep red blood cells as affected by supplemental vitamin E

Effects of dietary vitamin E on responses to SRBC antigens and Escherichia coli infection were studied in chicks from White Leghorn lines selected for 24 generations for high (HAS) and low (LAS) antibody responses to SRBC. Chicks were fed corn-soybean diets consisting of either high (300 IU per kg feed) or low (10 IU per kg feed) concentrations of vitamin E from the day of hatch through the end of experiment. The LAS chicks were heavier than the HAS chicks at 14 d of age and thereafter; there was no difference in BW between vitamin E concentrations. At 37 d of age, chicks were inoculated via the brachial vein with 0.1 mL of 0.25% SRBC suspension. Antibody titers at 6 and 10 d after inoculation were higher in HAS than in LAS chicks. At 6 and 10 d after inoculation with SRBC, antibody responses were lower in LAS chicks fed the diet containing the higher vitamin E concentration than in those fed the diet containing the lower concentration of vitamin E. At 64 d of age, chicks were injected in the posterior thoracic air sac with 0.1 mL of 10(-2) or 10(-4) dilution of Escherichia coli and scored for pericardial and air sac lesions. The HAS chicks were more susceptible to E. coli infection than LAS chicks as measured by lesion scores and BW changes. Although dietary vitamin E had no effect on lesion scores in either line, BW loss at 24 h after E. coli inoculation was significantly reduced in HAS chicks fed the higher concentration of vitamin E. The dosage of E. coli had no effect on lesion scores and BW changes. These results suggest that genetic selection might have changed immune competence in relation to responses to dietary vitamin E, and the optimum dietary concentration of vitamin E depends on genotype, among other factors.

Comparison of genetically engineered microbial and plant phytase for young broilers

This study was conducted to compare the efficacy of genetically engineered microbial (Natuphos) and plant (Phytaseed) phytase for enhancing the utilization of phytate P in corn-soybean meal-based diets fed to young broilers and to evaluate the safety of Phytaseed phytase. Three levels of each of the two sources of phytase (250, 500, and 2,500 U/kg of diet) were added to a corn-soybean meal basal diet containing 0.46% total P, 0.21% nonphytate P, and 0.92% Ca. There were eight cages per treatment (eight birds per cage for Weeks 2 to 3 and seven birds for Weeks 4 to 5), except for the basal diet without added phytase that had 16 cages. Cage BW and feed consumption were recorded weekly. During Week 5, cage excreta samples were collected for determination of apparent retention coefficients of DM, Ca, and P. At the end of Week 5, all birds were killed, and the left and right toes were removed for determination of toe ash weight and percentage. Forty birds (one per cage from the diet without added phytase and diets with 500 or 2,500 U phytase/kg from both sources) were randomly selected for gross necropsy and histologic evaluation of liver, kidney, and bone tissues. Addition of both sources of phytase resulted in similar increases (P < 0.05) of BW gain; feed intake; gain:feed; apparent retention of DM, P and Ca; and toe measurements. Phosphorus excretion decreased as phytase addition increased. No significant abnormalities were seen in any of the 40 broilers necropsied. Further, the fit of a nonlinear function revealed that most measurements reached a plateau at 2,500 U/kg. Based on performance, bone characteristics, and retention of P, Ca, and DM of young broilers, the efficacy of Phytaseed phytase was similar to that of Natuphos phytase for enhancing the utilization of phytate P in corn-soybean meal-based diets. General necropsy and histologic examination of liver, kidney, and tibial tissues revealed no adverse effects of phytase source or level.

Antibody responses to different dosages of sheep red blood cells in lines of chickens selected for high and low antibody response to sheep red blood cells

Temporal patterns of SRBC antibody response after primary and secondary inoculations were measured in White Leghorn males from lines selected 24 generations for high (HA) or low (LA) 5-d antibody titers to an i.v. inoculation with 0.1 mL of a 0.25% suspension of SRBC. Primary i.v. inoculations were administered at 50 d of age as 0.1 mL of either 0.025 or 0.25% suspension of SRBC. Antibody levels of SRBC were measured 3, 5, 7, 9, 11, 13, and 20 d after inoculation. Also, IgG levels were measured on samples obtained 3, 7, 13, and 20 d after inoculation. At 70 d of age, half of the cockerels in each line-dosage subclass were given a booster inoculation of 0.1 mL of 0.25% SRBC. The SRBC antibody was measured 3, 6, 9, and 13 d later in chicks both receiving and not receiving the second inoculation. Patterns of antibody response to SRBC dosage differed according to line, resulting in interactions of line by dosage by day. Concentrations of IgG were greater for Line HA than for LA at 7 and 11 d after inoculation with SRBC but not at 3 and 20 d. Antibody responses to the booster inoculation differed between lines with a dosage effect present for LA but not for HA chicks. The greater anamnestic response observed in LA than in HA chicks is explained in the context of the resource allocation paradigm.

Risk assessment of left ventricular systolic dysfunction in primary care: cross sectional study evaluating a range of diagnostic tests

OBJECTIVES

To assess the probability of left ventricular systolic dysfunction without echocardiography in patients from general practice.

DESIGN

Cross sectional study using multivariate regression models to examine the relation between clinical variables and left ventricular systolic dysfunction as determined by echocardiography.

SETTING

Three general practices in Copenhagen.

SUBJECTS

2158 patients aged >40 years were screened by questionnaires and case record reviews; 357 patients with past or present signs or symptoms of heart disease were identified, of whom 126 were eligible for and consented to examination.

MAIN OUTCOME MEASURES

Clinical variables that were significantly (P<0.05) related to ejection fraction </=0.45 and their predictive value for left ventricular systolic dysfunction.

RESULTS

15 patients (12%) had left ventricular systolic dysfunction. The prevalence was significantly related to three questions: does the electrocardiogram have Q waves, left bundle branch block, or ST-T segment changes? (P=0.012); is resting supine heart rate greater than the simultaneous diastolic blood pressure? (P=0.002); and is plasma N-terminal atrial natriuretic peptide>0.8 nmol/l? (P=0.040)? Only one of 60 patients with a normal electrocardiogram had systolic dysfunction (2%, 95% confidence interval 0% to 9%) regardless of response to the other two questions. The risk of dysfunction was appreciable in patients with a yes answer to two or three questions (50%, 27% to 73%).

CONCLUSIONS

A normal electrocardiogram implies a low risk of left ventricular systolic dysfunction. Patients can be identified for echocardiography on the basis of an abnormal electrocardiogram combined with increased natriuretic peptide concentration or a heart rate greater than diastolic blood pressure, or both.

[Right bundle branch block, ST segment elevation and sudden cardiac death. A clinical and electrocardiographic syndrome--Brugada syndrome]

The association of an abnormal electrocardiogram (ecg) consisting of right bundle branch block and ST segment elevation in leads V1-V3 and sudden arrhythmic death has been described in patients with no demonstrable structural heart disease. A patient with these ecg findings and aborted sudden death is presented. The patient had no structural heart disease and received an implantable cardioverter-defibrillator which seems to be the treatment of choice.

Experimental Cochlosoma anatis infections in poultry

Cochlosoma anatis [Kotlán, A., 1923. Zentralbl. Bakteriol. Parasitenkd. Infektienskr. Hyg. 90, pp. 24-28] is a flagellated protozoan parasite of birds. We have encountered C. anatis in turkeys with enteritis. Experimental oral inoculations of turkeys with 1 x 10(6) to 10 x 10(6) trophozoites consistently reproduced infections in recipients. Trophozoites were most numerous in the jejunum and ileum but could be observed in the duodenum, ceca, colon, and feces. When 12 naive turkeys were placed on contaminated litter vacated by excreting turkeys only one of 12 became infected. When eight naive turkeys were placed in boxes with birds currently excreting trophozoites, seven of eight became infected. Trophozoites could not survive exposure to water or to freezing. Attempts to culture trophozoites in modified Diamond's medium, Kiester's medium, RPMI 1640 medium with 10% fetal bovine serum, or on cultured bovine turbinate cells were not successful. Four of six bobwhite quail and one of eight chickens orally inoculated with 10 x 10(6) to 20 x 10(6) trophozoites had detectable infections. Trophozoites were observed only in the ilea of bobwhite quail and the ceca of the positive chicken. Trophozoites collected from chickens and bobwhite quail remained infectious for turkeys.

The effectiveness of benzimidazole derivatives for the treatment and prevention of histomonosis (blackhead) in turkeys

The benzimidazole derivatives, albendazole and fenbendazole were evaluated for their effectiveness in the treatment and prevention of histomonosis (blackhead) in turkeys. Histomonosis was produced in 5 week-old birds by placing them on broiler breeder litter known to be contaminated with Heterakis gallinae ova and the protozoan Histomonas meleagridis. In the first trial, at the onset of confirmed clinical disease, birds were treated orally with metronidazole, a compound known to be effective against Histomonas. Those receiving metronidazole had significantly greater mean body weight gains during the treatment period and the 2 weeks following treatment than untreated controls. Treated birds also had significantly lower caecal and liver lesion scores. These findings served to validate the method of disease reproduction and establish its suitability for testing the benzimidazoles. Similar trials were conducted to determine the therapeutic value of albendazole at 100.0 mg/kg of body weight and fenbendazole at 10.0 mg/kg body weight, administered orally twice a day for 5 consecutive days. Under these conditions, both drugs were found to be ineffective as treatments. A final trial was conducted to assess the prophylactic value of albendazole and fenbendazole administration. At the time of placement on contaminated litter, birds were medicated as previously described with the exception that treatment was continued for 14 consecutive days, the approximate incubation period for histomonosis. The trial was terminated on the 16th day. In the case of both albendazole and fenbendazole, treatment was associated with a significant increase in mean body weight gain and lower caecal and liver lesion scores. It is believed that the observed prophylactic effect may be attributed to the destruction of the transport vector e.g., Heterakis larvae, or to direct killing of the flagellated form of Histomonas which is normally found in the caecal lumen and is considered to be more sensitive to chemotherapeutic agents than the amoeboid form found in tissues.

Mode of inheritance of unselected traits in lines of chickens selected for high or low antibody response to sheep red blood cells. 1. Resistance to marble spleen disease virus and juvenile body weight

Two lines of White Leghorns that had undergone long-term selection for high (HH) or low (LL) antibody response to sheep red blood cell antigen(s) formed the nuclear lines for this experiment. Matings were made in a full diallel cross to produce in a single hatch from age-contemporary breeders the parental lines, reciprocal F1 and F2 crosses, and backcrosses for 16 progeny types. For males and females, there were parental line differences in BW to 42 d of age, after which there was decline between lines for males. Differences in BW between reciprocal F1 crosses and maternal heterosis declined with age, primarily reflecting dissipation of effects of egg weight. Heterosis of BW was dependent on the particular F1 cross and recombination effects were not important. At 50 d of age chicks were inoculated with either a 1 or 10% suspension of spleen extract from chickens infected with marble spleen disease virus (MSDV). A third group served as uninjected controls. Response to MSDV was evaluated by spleen weight 6 d after inoculation. Spleen weights relative to BW of control chicks were heavier for the HH than LL line with evidence from the crosses of sexlinkage and negative heterosis. Line LL chicks were more resistant to MSDV than Line HH chicks was F1 crosses intermediate to and different from either parental line with no evidence of heterosis.

The effect of stress on the response of chickens to coccidiosis vaccination

Six-week-old Leghorn chickens, which had been adapted to both their environment and cage mates, were orally inoculated with 400 Eimeria tenella oocysts as a means of low-dose vaccination. At 2, 3, 4, 5 or 6 days after vaccine administration, the birds were subject to 24 h of social stress through a prescribed method of random redistribution. Two weeks after vaccine administration, the birds were challenged by oral inoculation with 8000 oocysts. Caecal lesion scores were determined 6 days after challenge. Vaccinated chickens were more resistant to lesion formation than unvaccinated controls, and protection, as determined by lower lesion scores, was significantly enhanced when stress in the form of social disruption was applied on the fourth day following vaccine administration.

Effect of dietary selenium on the response of stressed and unstressed chickens to Escherichia coli challenge and antigen

Selenium was added to the feed of White Leghorn type chickens 1 day prior to challenge with either Escherichia coli or sheep erythrocyte antigen. The incidence of death or lesions was reduced from 86% to 21% at the optimal dose of selenium (0.4 mg/kg resulting in feed concentration of 0.45 mg/kg). After the chickens were stressed by chilling, selenium was ineffective against E. coli. Dietary additions of selenium between 0.1 and 0.8 mg/kg resulted in an antibody titer increase from 2.2 to 3.9 to the log2 against sheep erythrocytes (SRBC). Following chilling, antibody titer response was reduced from 4.9 to 2.4 to the log2. This titer reduction could be prevented with dietary additions of selenium between 0.1 and 1.2 mg/kg. The effects of a nitrofuran and selenium were additive against E. coli challenge infection.

Analysis of avian lymphocyte proliferation by a new, simple, nonradioactive assay (lympho-pro)

An assessment of T-cell-mediated immune functions (i.e., lymphocyte proliferation assay) in the chicken, unlike the determination of antibody levels, is not routinely performed. This is primarily because of difficulties in the isolation of relatively pure populations of lymphocytes and the use of radioactive isotopes. To address these issues, the goals of our study were to optimize a method for isolating and enriching avian lymphocyte populations and to develop a nonradioactive lymphocyte proliferation assay. To accomplish these goals, we used a multiple slow-speed centrifugation technique combined with a "swirl" collection technique for lymphocyte isolation from chicken peripheral blood. After a fraction enriched with lymphocytes was obtained, a simple, rapid colorimetric and fluorometric assay (lympho-pro) to indirectly determine mitogen-induced proliferation was adapted and compared with the "Gold Standard" [3H]thymidine. Chickens of different ages and two genetic strains were used in this study. Lymphocytes were stimulated with various concentrations of concanavalin A (Con A, T-cell mitogen) or phorbol 12-myristate 13-acetate + ionomycin (pan lymphocyte mitogen). Our studies showed that the pattern of lymphocyte proliferation assessed by the Alamar blue-based lympho-pro assay was similar to the [3H]thymidine incorporation assay. Younger birds had higher levels of mitogen-induced proliferation when compared with adults of the same genetic strain. Because the lympho-pro assay, unlike [3H]thymidine, does not require lysis of cells to assess proliferation, cells that have undergone stimulation/proliferation can be subsequently characterized by staining with antibodies against cell surface antigens and analysis by flow cytometry. Another notable advantage of the lympho-pro assay is the rapidity of assessment and nontoxicity. In conclusion, this assay may be of value in assessing some aspects of T-cell-mediated immunity in both avian research and avian medicine diagnostic settings.

The production of colibacillosis in turkeys following sequential exposure to Newcastle disease virus or Bordetella avium, avirulent hemorrhagic enteritis virus, and Escherichia coli

Female large white turkeys were intranasally inoculated with either Newcastle disease virus (ND) or Bordetella avium (BA) at 4 weeks of age. This was followed by oral inoculation with an avirulent (vaccine) strain of hemorrhagic enteritis virus (HE) at 5 weeks and intravenous inoculation with Escherichia coli (EC) at 6 weeks. Control birds received ND, BA, or HE followed by EC; EC alone; or nothing at all. Turkeys receiving one agent prior to EC challenge did not experience a significant increase in mortality or pericarditis. Those exposed to ND or BA followed by HE and EC experienced a significant elevation in mortality and pericarditis. A highly significant positive correlation between the number of infectious agents encountered during primary exposure and the incidence of colibacillosis after EC challenge was demonstrated.

Efficacy of anipamil, a phenylalkylamine calcium antagonist, in treatment of angina pectoris

To evaluate the efficacy of anipamil, a phenylalkylamine calcium antagonist, in treatment of stable angina pectoris, we performed a randomized, double blind placebo-controlled, cross-over study. Inclusion criteria were (a) stable angina pectoris for at least 2 months, (b) an exercise test with > or = 0.1-mV horizontal or downsloping ST-segment depression limited by angina, and (c) at least 10 attacks of angina pectoris in a single-blind 3-week run-in period. Nineteen patients were randomized to enter the study. In 3-week periods, they received either anipamil 80 mg once daily (o.d.), anipamil 160 mg o.d., or placebo. At the end of each period, an exercise test was performed. The number of angina pectoris attacks was significantly reduced during treatment with anipamil 80 mg (p < 0.05) and anipamil 160 mg (p < 0.001) as compared with placebo. Glycerol nitrate consumption was significantly reduced during treatment with anipamil 80 mg (p < 0.01) and 160 mg (p < 0.001) as compared with placebo. During exercise testing, the load (W) at start of angina was significantly increased during treatment with anipamil 80 mg (p < 0.01) and 160 mg (p < 0.05) as compared with placebo. Heart rate (HR) at 0.1 mV ST-segment depression was increased during treatment with anipamil 80 mg (p < 0.001). Few adverse events were reported.

Anipamil prevents ST depression in patients with stable angina pectoris

The purpose of this study was to examine the 24-hour antiischemic efficacy of once-a-day anipamil compared to placebo in the treatment of patients with stable angina. The study was designed as a double-blind, placebo-controlled crossover study with an initial 3 week single-blind placebo period. The patients received anipamil 80 mg once daily, anipamil 160 mg once daily, and placebo in a randomized order. At the end of each treatment period the patients underwent 24-hour ambulatory ECG recording. Nineteen patients were included, all with typical stable angina pectoris for at least 2 months, exercise test with > or = 0.10 mV horizontal or down-sloping ST-segment depression and limited by angina pectoris, and at least 10 attacks of angina pectoris in the initial single-blind placebo period. During the placebo period, a total duration of transient myocardial ischemia > or = 0.10 mV during the 24-hour ambulatory ECG monitoring period was 2263 minutes, 75% of which were asymptomatic. Anipamil 80 mg and 160 mg significantly reduced the duration of episodes to 712 minutes (p < 0.001), with 87% asymptomatic, and to 913 minutes (p > 0.001), with 92% asymptomatic, respectively. In conclusion, anipamil given once a day is an effective 24-hour antiischemic drug in the treatment of transient myocardial ischemia.

Research note: resistance of chickens to an outbreak of necrotic enteritis as influenced by major histocompatibility genotype and background genome

An outbreak of necrotic enteritis occurred in chickens that were B13B13 or B21B21 at the MHC in sublines of lines selected for high (HA) and low (LA) antibody response to sheep erythrocytes. Percentage mortality and hen-day egg production, although similar for both background genomes, were different for MHC genotypes. Mortality was 6% for B21B21 and 15% for B13B13 types. Although hen-day egg production for both types declined from about 76 to 50%, the decrease occurred earlier but recovery of survivors was faster in B13B13 than in B21B21 pullets.

Antibody responses to combinations of antigens in white Leghorn chickens of different background genomes and major histocompatibility complex genotypes

Antibody responses in chickens to SRBC, Newcastle disease (NDV), and Brucella abortus (BA) were compared when given singly or in combination. Chickens used in the present experiment originated from a cross and then backcrossing of White Leghorn populations that had been selected for high (HA) or low (LA) antibody response to SRBC antigens. The populations used in the current study were segregating for MHC haplotypes B13 and B21. The experiment had a 2 x 3 x 6 factorial arrangement of treatments (two background genomes: HA and LA; three MHC haplotypes: B13B13, B13B21, and B21B21; and six antigen treatments: SRBC, NDV, or BA only, SRBC plus NDV, SRBC plus BA, and NDV plus BA). Antigens were administered either i.v. (SRBC) or i.m. (NDV and BA) when chicks were 42 days of age. Blood was obtained 27 days later (69 days of age) for antibody determinations. A significant background genome by MHC haplotype interaction for BA antibodies was due to relatively high titers in Line HA chickens of MHC genotypes B13B13 and B13B21. Background genome by MHC genotype interactions were not significant for SRBC or NDV antibodies. Antibody titers to SRBC were higher in background genome HA than LA, and similar among MHC genotypes. Antibodies to NDV were lower in chickens of MHC genotype B21B21, but there were no differences due to background genome. For each of the three antigens, antibody responses were highest when administered singly rather than in combination. Antibody titers were lower for SRBC when given with BA, and for BA titers when given with NDV.(ABSTRACT TRUNCATED AT 250 WORDS)

Ulcerative cholecystitis produced by 3-nitro-4-hydroxy-phenylarsonic acid toxicosis in turkey poults

Naturally occurring ulcerative cholecystitis was present in a flock of 21-day-old turkey hens that were accidentally given at least 0.004% 3-nitro-4-hydroxy-phenylarsonic acid (3-NITRO) in their water for 2 days. Similar lesions were reproduced by administering 0.002% 3-NITRO to 2-day-old turkey poults for 6 days. Turkeys 31 days old were given up to 0.004% 3-NITRO in their water for 6 days, but no gall bladder ulcers were present in these poults. The toxicity to turkeys of 3-NITRO in the water appears to be age-dependent.

Effect of halothane, isoflurane, and pentobarbital anesthesia on myocardial irritability in chickens

The relative myocardial irritant properties of halothane, isoflurane, and pentobarbital were evaluated in chickens. Sixteen adult male broiler chickens were randomly assigned to 1 of 3 groups: group-1 chickens were anesthetized with pentobarbital (30 mg/kg, IV), group-2 chickens were anesthetized with halothane (end tidal halothane 1.2%), and group-3 chickens were anesthetized with isoflurane (end tidal isoflurane 2.1%). Birds in any 2 of the 3 treatment groups were tested on any 1 day. Local anesthesia was induced, and blood pressure, heart rate, ECG, and blood gas variables were measured before general anesthesia was induced. Positive-pressure ventilation with an inspired O2 fraction greater than 0.95 was adjusted to result in an end tidal CO2 concentration that reflected a Paco2 similar to that obtained prior to anesthesia and ventilation. All measurements were repeated. The threshold for ventricular fibrillation in response to electrical stimulation of the heart was then determined for all birds. Effects of anesthesia on hemodynamic and blood gas variables were similar in all 3 groups. Compared with halothane or pentobarbital, isoflurane anesthesia resulted in a significantly (P less than 0.05) lower threshold for electrical fibrillation of the heart.

Effect of age and growth rate on myocardial irritability in broiler chickens

Young broiler chickens are undergoing a period of extremely rapid growth and may be expected to be in a state of extreme endocrine and biochemical flux. These birds are also subject to a sudden death syndrome of unknown etiology. We hypothesized that an increased myocardial sensitivity in birds exhibiting early rapid growth may contribute to this syndrome. The objective of the current study was to investigate the interaction between early growth rate and age on myocardial irritability in young broiler chickens. This study utilized 74 male broiler chickens between 3 (Group A, 21-24 days) and 6 (Group B, 43-47 days) weeks of age exhibiting rapid (heavy weight, greater than 425 g at 2 weeks) and slow (low weight, less than 350 g at 2 weeks) early growth. Physiologic parameters such as blood pressure, heart rate, and arterial blood gases in the awake, restrained birds were essentially unchanged across these groups. Myocardial irritability of the anesthetized bird (pentobarbital) as measured by the threshold to electrical fibrillation was significantly increased only in the Group A HW birds. The results of this study suggest an increased myocardial irritability in large young broilers (3 weeks of age) that is no longer present in a similar group of older birds (6 weeks of age). These findings are consistent with the hypothesis that there is an increased myocardial sensitivity in birds succumbing to sudden death syndrome, with death due to myocardial fibrillation. Further research is needed to determine the mechanisms involve.

Turkey poult tolerance to diets containing deoxynivalenol (vomitoxin) and salinomycin

Feed taken from a commercial turkey farm where poults had refused to eat the feed and high mortality had occurred was analyzed and found to contain .81 mg/kg vomitoxin and 2.2 mg/kg salinomycin. The present four experiments investigated the effects of diets containing salinomycin at 0, 2.2, 5.5, 11, and 22 mg/kg and vomitoxin at 0, 2.2, and 4.4 mg/kg. A factorial design with vomitoxin at 0 and 4.4 mg/kg and salinomycin at 0 and 22 mg/kg was used in Experiment 4. Poults fed the suspect commercial diet had significantly lower feed consumption and higher motality than poults fed a control diet (P less than .05). Poults (0 to 3 wk of age) fed diets containing vomitoxin (4.4 mg/kg), salinomycin (22 mg/kg), or both showed no significant decrease in feed consumption, body weight gain, or viability.

Effect of oxytetracycline-hydrochloric acid on reproduction of female turkeys

Effects of oxytetracycline-HCl on reproductive performance of turkey breeder hens from the 13 to 24-wk production period were evaluated. During the 13th wk of production, females were grouped into low, medium, and high fertility subclasses. Females within each fertility subclass were randomly reassigned to treatments. The antibiotic was administered via the drinking water (T-2) or via the drinking water plus an intravaginal lavage (T-3). Hens receiving T-2 treatment showed significantly higher fertility than untreated controls (T-1) but also showed significantly higher early embryonic mortality than those receiving the T-3 treatment. Hatchability of all egg set was significantly higher in both antibiotic-treated groups than in controls. Females in the fertility subclasses remained significantly different from each other throughout the experiment. To determine the duration of the effect of antibiotic treatment, eggs were collected in a treatment and posttreatment periods. Fertility (P less than .05), and hatchability (P less than .10) were improved during the treatment period compared with results of the posttreatment period. The T-3 treatment had a long-term effect: it maintained early embryonic mortality at 10% and hatchability at the same level during both treatment periods. A short-term effect was observed in the T-2 group; early embryonic mortality increased (P less than .05) and hatchability decreased (P less than .10) during the posttreatment period. No correlations were found between mycoplasmal or bacterial populations and fertility subclass or antibiotic treatment. Egg production, body weight, feed consumption, feed consumed per egg, egg weight, and egg specific gravity were unaffected by antibiotic treatment.

Dihydroergotamine and mobilization after major orthopedic surgery

The effects of dihydroergotamine (DHE) on the degree of mobilization and response to orthostatic stress after total hip arthroplasty were studied. In the mobilization study, 78 patients received DHE, 0.5 mg im, twice a day from the day of surgery until full mobilization was achieved. Eighty-four patients who received placebo served as controls. There was no significant difference in the time until the first day of mobilization or the degree of mobilization. In the orthostatic test condition, subgroups of 61 patients receiving placebo and 55 patients receiving DHE were subjected to orthostatic testing. There were no differences in cardiovascular response to bed rest or in orthostatic stress. We conclude that DHE does not stabilize the cardiovascular reaction to orthostatic stress, nor does it enhance mobilization in patients after total hip arthroplasty.

Field outbreaks of colibacillosis of turkeys associated with hemorrhagic enteritis virus

In a study of field material and a survey conducted by the authors, typical signs of colibacillosis of 6-to-12-week-old poults included sudden onset, listlessness, rales, and high mortality. Signs persisted for about 2 weeks and were often followed by a low incidence of lameness caused by Escherichia coli. Gross lesions included enlarged and congested spleens and livers, and dilated discolored black or purple duodenal loops. Microscopic lesions included splenic and hepatic congestion. In some birds (freshly killed and fixed immediately), the epithelium at the tips of the duodenal villi was sloughing, but in other birds the villi were intact and normal in appearance. Splenic enlargement, the presence of intranuclear splenic inclusions similar to those found in hemorrhagic enteritis (HE), and the isolation of HE virus from some of the field spleens all indicated that inapparent HE infection often occurs at approximately the same time as this type of colibacillosis. It is therefore believed that HE infection often exacerbates colibacillosis of older poults.

Colibacillosis of turkeys exacerbated by hemorrhagic enteritis virus. Laboratory studies

Lesions typical of colibacillosis disease were reproduced in laboratory experiments. Mortality resulting from experimentally produced colibacillosis was significantly increased when Escherichia coli O1:K1 was presented to poults that had been orally inoculated with hemorrhagic enteritis virus (HEV) 1 week earlier. These and previous data suggest that HEV infection can exacerbate colibacillosis of older poults. HEV infection apparently damages the poults' defense system enough to account for the observed increase in susceptibility to E. coli.

Contact probe for corneal temperature measurements

A thermistor probe for corneal temperature measurements is presented. The temperature-sensing cartridge is similar in shape to an electronic tonometer, and the procedure of corneal temperature registration is performed just as easily and in a similar manner as for tonography.

Immunity to transmissible (coronaviral) enteritis of turkeys (bluecomb)

Turkey flocks recovering from natural and laboratory induced coronaviral enteritis developed lifelong immunity. Virus neutralization tests indicated that neutralization capacity of serums from recovered turkeys was low. One-way cross challenge test using turkeys inoculated with various bluecomb isolates revealed close antigenic relationship or antigenic identity among bluecomb isolates. The controlled application of intestinal preparations containing coronavirus as a vaccination procedure had value in developing active lasting immunity but it has limitations in areas that are attempting to eliminate the disease by a depopulation program. Killed vaccines injected parenterally did not produce a detectable immunity.