Hepatitis C virus infection and biological false-positive syphilis tests

BACKGROUND

The diagnosis of syphilis requires two-step serological testing. Not infrequently, sensitive screening tests are reactive but are not confirmed by more specific confirmatory tests yielding a biological false positive (BFP). This study sought to describe the prevalence of BFP in a large population of hepatitis C virus (HCV)-infected and uninfected women.

METHODS

A cross-sectional serosurvey of HIV-seropositive and HIV-seronegative women enrolled in the Women's Interagency HIV Study, a multicentre collaborative study of the natural history of HIV in women.

RESULTS

Among HCV-infected women 4% had a BFP compared with 1% among those who were HCV uninfected (odds ratio (OR) 3.3, 95% CI 2.1 to 5.1). Controlling for both HIV infection and a history of intravenous drug use among all tests for syphilis a BFP also occurred more commonly in HCV-infected women compared with HCV-uninfected women (6% vs 1%, OR 7.62, 95% CI 1.9 to 12.5).

CONCLUSION

HCV infection is associated with various effects on immune function including alterations in serological test results. Women with HCV are more likely to have a BFP syphilis test than women without HCV.

Effect of pimobendan or benazepril hydrochloride on survival times in dogs with congestive heart failure caused by naturally occurring myxomatous mitral valve disease: the QUEST study

BACKGROUND

Myxomatous mitral valve disease (MMVD) continues to be an important cause of morbidity and mortality in geriatric dogs despite conventional therapy.

HYPOTHESIS

Pimobendan in addition to conventional therapy will extend time to sudden cardiac death, euthanasia for cardiac reasons, or treatment failure when compared with conventional therapy plus benazepril in dogs with congestive heart failure (CHF) attributable to MMVD.

ANIMALS

Two hundred and sixty client-owned dogs in CHF caused by MMVD were recruited from 28 centers in Europe, Canada, and Australia.

METHODS

A prospective single-blinded study with dogs randomized to PO receive pimobendan (0.4-0.6 mg/kg/d) or benazepril hydrochloride (0.25-1.0 mg/kg/d). The primary endpoint was a composite of cardiac death, euthanized for heart failure, or treatment failure.

RESULTS

Eight dogs were excluded from analysis. One hundred and twenty-four dogs were randomized to pimobendan and 128 to benazepril. One hundred and ninety dogs reached the primary endpoint; the median time was 188 days (267 days for pimobendan, 140 days for benazepril hazard ratio = 0.688, 95% confidence limits [CL]=0.516-0.916, P= .0099). The benefit of pimobendan persisted after adjusting for all baseline variables. A longer time to reach the endpoint was also associated with being a Cavalier King Charles Spaniel, requiring a lower furosemide dose, and having a higher creatinine concentration. Increases in several indicators of cardiac enlargement (left atrial to aortic root ratio, vertebral heart scale, and percentage increase in left ventricular internal diameter in systole) were associated with a shorter time to endpoint, as was a worse tolerance for exercise.

CONCLUSIONS AND CLINICAL IMPORTANCE

Pimobendan plus conventional therapy prolongs time to sudden death, euthanasia for cardiac reasons, or treatment failure in dogs with CHF caused by MMVD compared with benazepril plus conventional therapy.

Prospective in vitro testing for drug-induced neutropenia in a patient requiring anti-malarial prophylaxis: confirmation of findings on exposure of patient to drug

A patient with moderate pancytopenia thought to be due to chloroquine ingestion was shown to have granulocyte progenitors (CFU-G) which were abnormally sensitive in vitro to chloroquine. As he required further anti-malarial prophylaxis, his marrow was prospectively tested in vitro with proguanil and its metabolite cycloguanil. The patient's CFU-G were also abnormally sensitive to these agents and predicted neutropenia was verified when the patient had a trial course of proguanil. We believe this is the first instance of in vivo confirmation of in vitro CFU-G drug sensitivities.

Collection of the BD SurePath Pap Test with a broom device plus endocervical brush improves disease detection when compared to the broom device alone or the spatula plus endocervical brush combination

Objective:

Here we examine the diagnostic utility of the US Food And Drug Administration (FDA) approved Spatula + endocervical brush combination for the BD SurePath Pap Test (SPPT) and compare it to SPPT collection with the broom alone or to an off-label combination of broom + EC brush. This question is important due to lingering concerns over the value of EC detection to a satisfactory Pap test.

Methods:

20,125 SPPT vials were examined for the collection devices contained. The SPPT collection device combinations allowed were: Rovers Cervex-Brush (broom, FDA approved), Medscand Pap Perfect Spatula + Medscand CytoBrush Plus GT (spatula + GT brush, FDA approved) or Rovers Cervex-Brush + Surgipath C-E Brush (broom + CE brush, off label).

Results:

Examination of SPPT vials revealed 11,130 collected with the broom, 4,687 collected with the spatula + GT brush and 2,921 collected with the broom + CE brush. Absence of an endocervical/transformation zone was seen in 22.86% of broom cases, 13.10% of spatula + GT brush cases (p= 0.00005 vs broom) and 10.17% of broom + CE brush cases (p= 0.00005 vs broom, p= 0.00005 vs spatula + GT brush). Importantly, LSIL detection was: broom 2.99%; spatula + GT brush 2.45% (p= 0.053 vs broom); broom + CE brush 4.18% (p= 0.034 vs broom, p= 0.0001 vs spatula + GT brush).

Conclusion:

When broom + brush combination is compared to broom alone or to spatula + GT brush, the broom + CE brush combination better sampled the endocervical/transformation zone and increased LSIL detection.

Atrial myocarditis as a cause of sinus arrest in a dog

A 10-year-old male cairn terrier cross was presented with a history of myxomatous mitral valve disease diagnosed six months previously and with a four-week history of intermittent collapse. On 24 hour electrocardiograph (Holter) analysis, periods of no discernable electrical cardiac activity, which coincided with three collapsing episodes, were identified. Unfortunately, on re-presentation for removal of the Holter monitor, the dog collapsed and died. A post-mortem examination was conducted, and histology of the right and left atrium showed evidence of myocarditis. This is the first reported case, to our knowledge, of collapse because of electrical asystole in a dog with atrial myocarditis.

Pulsus alternans in English cocker spaniels with dilated cardiomyopathy

OBJECTIVES

To report the clinical findings associated with pulsus alternans in English cocker spaniels with dilated cardiomyopathy and to review the phenomenon of mechanical alternans, usually found in patients with severe left ventricular systolic dysfunction.

METHODS

The case records of 10 English cocker spaniels with dilated cardiomyopathy and pulsus alternans were reviewed. All dogs had been referred in moderate to severe congestive heart failure. Pulsus alternans was clinically recognised by palpation of a regular alternation of femoral pulse amplitude and confirmed by echocardiography in all cases. Pulsus alternans was an intermittent finding in all 10 dogs.

RESULTS

Phonocardiographic recordings were obtained in three dogs to document variation in the intensity of the heart sounds, with one case exhibiting absence of the second heart sound in alternate beats. M-mode echocardiography performed in all dogs showed alternation of the pattern of mitral valve diastolic motion. Doppler echocardiography showed marked alternation in stroke volume in the aortic outflow in all cases. It also showed alternation in mitral regurgitation and in the velocity of early ventricular filling.

CLINICAL SIGNIFICANCE

Pulsus alternans may be more prevalent in English cocker spaniels than in other breeds, and because of its intermittent nature, its incidence may be higher than that previously reported. It has diagnostic relevance as it usually indicates severe myocardial depression. Echocardiography allows non-invasive detection of mechanical alternans and provides further insights into its pathophysiology and clinical significance.

Pulsed tissue Doppler imaging in normal cats and cats with hypertrophic cardiomyopathy

Myocardial motion was quantified in normal cats (n = 25) and cats with hypertrophic cardiomyopathy (HCM) (n = 23) using the pulsed tissue Doppler imaging (TDI) technique. A physiologic nonuniformity was documented in the myocardial motion of normal cats, which was detected as higher early diastolic velocities, acceleration, and deceleration in the interventricular septum compared with the left ventricular free wall (LVFW). HCM cats exhibited lower early diastolic velocities, acceleration, and deceleration and also prolonged isovolumic relaxation time compared with normal cats. These differences were detected mainly along the longitudinal axis of the heart. A cutoff value of E' in the LVFW along the longitudinal axis >7.2 cm/s discriminated normal from HCM cats with a sensitivity of 92% and a specificity of 87%. The physiologic nonuniformity of myocardial motion during diastole was lost in affected cats. Systolic impairment (decreased late-systolic velocities in most segments along the longitudinal axis and decreased early systolic acceleration in both mitral annular sites) was evident in HCM cats irrespective of the presence of left ventricular outflow tract obstruction and congestive heart failure. Postsystolic thickening was recorded in the LVFW along the longitudinal axis only in affected cats (n = 6) and was another finding indicative of systolic impairment in the HCM of this species. This study identified both diastolic and systolic impairment in cats with HCM compared with normal cats. The study also documents the normal physiologic nonhomogeneity in myocardial motion in cats and the subsequent loss of this feature in the HCM diseased state.

68 GENE EXPRESSION COMPARISONS BETWEEN BOVINE IN VIVO AND CLONED EMBRYOS PRODUCED BY THREE DIFFERENT METHODS

Developmental pathways in the mammalian embryo are profoundly influenced by the epigenetic interaction of the environment and the genome. Loss of epigenetic control has been implicated in aberrant gene expression and altered imprinting patterns with consequence to the physiology and viability of the conceptus. Bovine somatic cell nuclear transfer (SCNT) is contingent on in vitro culture, and both SCNT and culture conditions are known to induce changes in embryonic gene expression patterns. Using these experimental models, this study compared gene expression of Day 7 cloned blastocysts created from three different SCNT protocols using the same cell line, with Day 7 in vivo blastocysts to elucidate mechanisms responsible for variations in phenotypic outcomes. SCNT methods included: (1) traditional SCNT by subzonal injection (SI); (2) handmade cloning (HMC); and (3) modified serial nuclear transfer (SNT), developed within the group. Four imprinted genes (Grb10, Ndn, Nnat, and Ube3a), four chromatin remodeling genes (Cbx1, Cbx3, Smarca4, and Smarcb1) and two genes implicated in polycystic liver disease (Prkcsh and Sec63) were analyzed in single blastocysts from each treatment (n = 5). All blastocysts expressed Actin, Oct-4 and Ifn-tau. All genes were sequence verified. Several genes were expressed ubiquitously across all groups, including Ndn, Ube3a, Cbx1, Cbx3, and Smarcb1. Interestingly, Grb10 was not expressed in two HMCs and one SNT blastocyst. Nnat was weakly expressed in one in vivo blastocyst and in the majority of cloned blastocysts in all groups. Prkcsh and Sec63 were expressed in all but one HMC blastocyst. While gene expression patterns were mostly maintained following SCNT, the imprinted genes Nnat and Grb10 showed instances of differential or abnormal expression in SCNT embryos. The chromatin remodeling genes were maintained in all SCNT treatments. Prkcsh and Sec63 were both absent in one HMC blastocyst, with implications for liver dysfunction, a condition previously reported in abnormal cloned offspring. The variable mRNA expression following SCNT provides an insight into genetic and environmental factors controlling implantation, placentation, organ formation, and fetal growth.

220 AN EXPRESSION PROFILE OF GENES CRUCIAL FOR PLACENTAL DEVELOPMENT IN SINGLE IN VIVO, IN VITRO AND CLONED BOVINE BLASTOCYSTS

Abnormalities of the placenta are a major factor contributing to early death in cloned bovine conceptuses. This is primarily due to incomplete chromatin remodeling and reprogramming of the donor nucleus. It is unknown whether genetic aberrations of genes crucial for placental development can be detected in pre-implantation cloned bovine embryos. This study looked at the expression profile of four genes in single bovine blastocysts derived from in vivo, in vitro produced (IVP), or cloning techniques, including handmade cloning (HMC) and serial HMC (SHMC). The genes studied included acrogranin, caudal type homeobox 2 (cdx2), estrogen-receptor-related receptor beta (essrb), and the mammalian relative of DnaJ (MRJ). These genes play a role in trophoblast regulation and placental development. Messenger RNA expression was analyzed by using PCR following cDNA amplification by means of SMART cDNA synthesis (Clontech, Palo alto, CA, USA). Primers were designed from homologous human and mouse sequence. PCR products were sequenced for verification. Five single blastocysts were analyzed from each of the following treatments: in vivo, IVP, HMC, and SHMC. Pooled (n = 10) IVP blastocyst cDNA produced by standard RT was used as a positive control. Grade 1 Day 7 blastocysts were selected for all treatments. Amplified cDNA was tested using control genes polyA, IFN-τ and GDF9. In vitro-produced embryos were matured, fertilized and cultured as published by Ruddock et al. (2004 Biol. Reprod. 70, 1131). Cloned HMC embryos were produced as described by Tecirlioglu et al. (2003 Reprod. Fertil. Dev. 15, 361). Serial HMC embryos were produced as per the HMC embryos, followed by a second round of nuclear transfer at the pronuclear stage. The pooled IVP, in vivo, and IVP blastocysts expressed all four genes of interest. In the HMC-cloned embryos, all four genes were expressed. However, in the SHMC cloned embryos, although MRJ was found to be expressed in all blastocysts, three of the five blastocysts did not express acrogranin. Similarly, two SHMC embryos did not express cdx2, and essrb was weakly expressed in three of the five embryos analyzed. Initial pregnancy rates of HMC and SHMC embryo transfers are similar. Further pregnancy results are pending. These results indicate that aberrations of genes crucial for placental development can be detected in single cloned blastocysts. It also suggests that failed implantation and/or placental defects may stem from patterned genetic defects in the pre-implantation embryo. An increase in the number of embryos analyzed would further strengthen results. These genes could act as markers to identify cloning techniques that produce more embryos with normal genetic profiles. The benefits of developing a screening tool to assess abnormalities in single pre-implantation embryos would be significant.

74 ANATOMICAL ABNORMALITIES IN CALVES PRODUCED BY NUCLEAR TRANSFER

Two limitations currently restrict the acceptability and adoption of bovine cloning as a commercial reality. The first of these is its low rate of efficiency and the second is that some of the cloned calves are not healthy. Abnormalities in the placenta are thought to contribute to many of the losses in early gestation; however, less is known of the pathology of clone deaths in the perinatal period. To date, the majority of perinatal deaths have been attributed to the “large offspring syndrome” characterized by increased birth weight and a range of morphological abnormalities thought to be associated with in vitro culture and manipulation. This report describes multi-systemic abnormalities in aborted, stillborn, and neonatal genetically modified and unmodified cloned calves weighing less than 60 kg at birth and aged between 6 months gestation and 3 weeks postnatal, generated in various experiments. Three of 14 genetically modified cloned calves had cystic renal dysplasia and osteopetrosis. All three and a fourth had irregular nodular, fibrotic livers with biliary abnormalities. Another two had marked flexion of the fetlock joints. Eleven calves derived from an unmodified cloned cell line by nuclear transfer had nodular, fibrotic livers with biliary anomalies, 9 of 11 had cystic renal dysplasia and cardiomegaly, two had osteopetrosis, and two had contracted tendons. In addition, three calves had polymicrocerebral gyri, two had retinal dysplasia, and one had an aortic aneurysm. Only one calf from a second unmodified cloned cell line produced by nuclear transfer had no significant congenital abnormalities. All calves were negative for bovine virus diarrhea virus (BVDV) by competitive-antigen ELISA, and by virus isolation and no BVDV antibodies were detected by AGID assay. Furthermore, all cell lines and media used were negative for BVDV by virus isolation. Two calves were tested and found to be negative for Akabane virus and Aino virus. There are very few reports of the pathological abnormalities of cloned animals. Similar multi-systemic abnormalities have not been found in non-cloned calves, but several analogous conditions occur in humans, including Simpson-Golabi-Behmel and Zellwegers syndromes. Further ultrastructure studies and genetic analysis are needed to investigate the mechanisms of these multi-systemic disorders, which may ultimately elucidate mechanisms for improved reprogramming and increase the efficiency of generating cloned animals with somatic cells by nuclear transfer.

235 THE INVESTIGATION OF mRNA EXPRESSION OF SEVERAL CHROMATIN REMODELLING GENES DURING BOVINE PREIMPLANTATION DEVELOPMENT

The efficiency of obtaining live calves from somatic cell nuclear transfer remains quite low. One factor implicated in this failure is inadequate chromatin remodelling of the donor nucleus. Five Polycomb group (PcG) genes were investigated as potential remodelling factors in bovine oocytes and preimplantation embryos. These genes (Cbx6, Eed, Edr1, Yy1, and Zfp144) are involved in transcriptional activation and cell cycle regulation. We hypothesize that inadequate expression may cause the developmental abnormalities seen following cloning. This study is aimed at characterizing normal expression, prior to comparative studies with cloned embryos. Three single abattoir-derived in vitro-matured (IVM) oocytes or in vitro-produced (IVP) embryos from each of the following stages: 2-cell, 4-cell, 8-cell, 16–32 cell, morula, Day 7 blastocyst, and Day 8 hatched blastocyst, were studied. Messenger RNA was isolated from individual samples with Dynabeads (Dynal, Inc., Lake Success, NY, USA) and then cDNA was created and amplified with a SMART cDNA synthesis kit (BD Biosciences Clontech, Palo Alto, CA, USA). Products were diluted 1:10 and used to amplify target genes by PCR. PCR products were sequenced for confirmation of identity. All amplified embryo samples expressed the housekeeping genes Poly(A) polymerase and actin. Similarly, all embryos up to the 8-cell stage expressed GDF9, an oocyte-specific gene, while IFN-tau, involved in maternal recognition of pregnancy, was expressed in one morula and all blastocyst samples. Cbx6 was not expressed at any stage. The other four genes were all expressed fairly consistently throughout the pre-implantation period. Eed transcript was detected in all samples, with the exception of one oocyte, one 4-cell embryo, and one 8-cell embryo. Edr1 transcript was detected in all samples except for two oocytes, one 16–32-cell embryo, and one Day 7 blastocyst. Yy1 was expressed in all but one oocyte, one 2-cell embryo, two 4-cell embryos, and one Day 7 blastocyst. Finally, Zfp144 transcript was detected in one oocyte and in all embryos until the 16–32 stage, and then was not detected until seen in one Day 7 and all Day 8 blastocysts. Cbx6, yet to be fully characterized in any species, is also known as the neuronal pentraxin receptor, and is involved in transport and clearance of synaptic debris. It is known to have the characteristic chromobox domain of the Cbx family, of which several family members play a role during pre-implantation development. Eed, Edr1, Yy1, and Zfp144 are expressed throughout the pre-implantation period, although levels of Zfp144 mRNA appear to drop during the embryonic genome activation and then reappear by the late blastocyst stage. This consistent expression may suggest a role for the proteins in chromatin remodelling or modulating patterns of gene expression in early development. Further studies are required to determine if these factors are expressed incorrectly in cloned embryos, potentially providing a link to the abnormalities observed post nuclear transfer.

Pulmonic stenosis in dogs: balloon dilation improves clinical outcome

Medical records of 81 dogs with severe pulmonic stenosis from 2 referral centers were examined retrospectively. Forty dogs underwent balloon valvuloplasty (BV), which was performed by 1 operator, whereas 41 did not. The mean age at latest follow-up was 41.5 months. A statistical comparison of the clinical outcome and survival was performed. Dogs revealing clinical signs at presentation showed a 16-fold increase in risk of death compared with asymptomatic dogs (P < .001). Statistical analyses demonstrated that an increase of 1 mm Hg in transstenotic pressure gradient (PG) at presentation was associated with a 3% increase in hazard rate (P < .001). Thirty-seven dogs survived BV with a median reduction in PG of 46%. The median preoperative PG was 120 mm Hg, and median PG 24 hours postoperatively was 55 mm Hg with a median of 55 mm Hg 6 months post-BV. Twenty (49%) of the non-BV (NBV) dogs remained asymptomatic at last follow-up. Fourteen (34%) of the NBV dogs died or were euthanized because of heart disease related to pulmonic stenosis. Twelve of these dogs died suddenly, whereas only 1 of the BV dogs died suddenly. After adjusting for PG, clinical signs at presentation, and age, BV or dilation was associated with a 53% reduction in hazard rate (P = .005). This study indicates that BV, when performed by an experienced operator, appears to be successful both in alleviating clinical signs and in prolonging survival in dogs with severe pulmonic stenosis.