Effect of amlodipine on the circulating renin-angiotensin-aldosterone system in healthy cats

BACKGROUND

Systemic hypertension (SH) is a common cardiovascular disease in older cats that is treated primarily with the calcium channel blocker amlodipine besylate (AML). The systemic effect of AML on the classical and alterative arms of the renin-angiotensin-aldosterone system (RAAS) in cats is incompletely characterized.

HYPOTHESIS/OBJECTIVES

To determine the effect of AML compared to placebo on circulating RAAS biomarkers in healthy cats using RAAS fingerprinting.

ANIMALS

Twenty healthy client-owned cats.

METHODS

Cats were administered amlodipine besylate (0.625 mg in toto) or placebo by mouth once daily for 14 days in a crossover design with a 4-week washout period. Plasma AML concentrations and RAAS biomarker concentrations were measured at multiple timepoints after the final dose in each treatment period. Time-weighted averages for RAAS biomarkers over 24 hours after dosing were compared between treatment groups using Wilcoxon rank-sum testing.

RESULTS

Compared to placebo, AML treatment was associated with increases in markers of plasma renin concentration (median 44% increase; interquartile range [IQR] 19%-86%; P = .009), angiotensin I (59% increase; IQR 27-101%; P = .006), angiotensin II (56% increase; IQR 5-70%; P = .023), angiotensin IV (42% increase; -19% to 89%; P = .013); and angiotensin 1-7 (38% increase; IQR 9-118%; P = .015).

CONCLUSIONS AND CLINICAL IMPORTANCE

In healthy cats, administration of AML resulted in nonspecific activation of both classical and alternative RAAS pathways.

Comprehensive characterization of the effect of mineralocorticoid receptor antagonism with spironolactone on the renin-angiotensin-aldosterone system in healthy dogs

OBJECTIVE

To characterize the dose-exposure-response effect of spironolactone on biomarkers of the classical and alternative arms of the renin-angiotensin-aldosterone system (RAAS) in healthy dogs.

ANIMALS

Ten healthy purpose-bred Beagle dogs.

PROCEDURES

Study dogs were randomly allocated to 2 spironolactone dosing groups (2 mg/kg PO q24hr, 4 mg/kg PO q24hr). The dogs received 7-day courses of spironolactone followed by a 14-day washout period in a crossover (AB/BA) design. Angiotensin peptides and aldosterone were measured in serum using equilibrium analysis, and plasma canrenone and 7-α-thiomethyl spironolactone (TMS) were quantified via liquid chromatography-mass spectrometry/mass spectroscopy (LC-MS/MS). Study results were compared before and after dosing and between groups.

RESULTS

Following spironolactone treatment, dogs had a significant increase in serum aldosterone concentration (P = 0.07), with no statistical differences between dosing groups. Significant increases in angiotensin II (P = 0.09), angiotensin I (P = 0.08), angiotensin 1-5 (P = 0.08), and a surrogate marker for plasma renin activity (P = 0.06) were detected compared to baseline following spironolactone treatment during the second treatment period only. Overall, changes from baseline did not significantly differ between spironolactone dosages. RAAS analytes were weakly correlated (R < 0.4) with spironolactone dosage and plasma canrenone or plasma TMS. There were no adverse clinical or biochemical effects seen at any spironolactone dosage during treatment.

CONCLUSIONS

Treatment with spironolactone increased serum aldosterone concentration in healthy dogs and impacted other biomarkers of the classical and alternative arms of the RAAS. There was no difference in effect on the RAAS between 2 and 4 mg/kg/day dosing. Dosage of 4 mg/kg/day was safe and well-tolerated in healthy dogs.

Efficacy of a mitral regurgitation severity index to predict long-term outcome in dogs with myxomatous mitral valve disease

BACKGROUND

Predicting progression of myxomatous mitral valve disease (MMVD) in dogs can be challenging.

HYPOTHESIS/OBJECTIVES

The mitral regurgitation severity index (MRSI) will predict time to congestive heart failure (CHF) and all-cause death in dogs with MMVD.

ANIMALS

Eight hundred sixty-nine client-owned dogs.

METHODS

Retrospective study pooling data from 4 previous samples including dogs with MMVD stage B2 or C. MRSI was calculated as: (heart rate [HR]/120) × left atrium-to-aorta ratio (LA:Ao) × (age in years/10) × 100. Alternative MRSI formulas substituting radiographic measures of left atrial size were also calculated. Cox proportional hazard modeling and time-dependent receiver-operator characteristic curves quantified prognostic performance.

RESULTS

For Stage B2 pooled samples, MRSI > 156 was predictive of time to CHF (median 407 vs 1404 days; area under the curve [AUC] 0.68; hazard ratio 3.02 [95% CI 1.9-4.9]; P < .001). MRSI > 173 was predictive of all-cause death (median survival 868 vs 1843 days; AUC 0.64; hazard ratio 4.26 [95% CI 2.4-7.5]; P < .001). MRSI showed superior predictive value compared to the individual variables of HR, LA:Ao, and age. Variations of the MRSI equation substituting radiographic vertebral left atrial size for LA:Ao were also significantly predictive of outcome in stage B2. MRSI was not consistently predictive of outcome in Stage C.

CONCLUSIONS AND CLINICAL IMPORTANCE

MRSI was predictive of outcome (onset of CHF and all-cause death) in MMVD Stage B2, demonstrating utility as a useful prognostic tool. Echocardiographic LA:Ao can be effectively replaced by radiographically determined LA size in the MRSI formula.

Experimental dataset of the impact assessment of vegetable intercropping on agroeconomic performances, pests and beneficials, and soil resources

The data presented in this article were collected in the field at an experimental station in southern France under a Mediterranean climate. Experiments were conducted under three plastic walk-in tunnels used as blocks with organic farming practices over two successive years in a completely randomized design. The aim was to compare the intercropping of sweet pepper with basil, onion, lettuce, parsley or French bean to a sole crop of sweet pepper used as a control. The dataset provides information on cultural practices with details on inputs and working times used to estimate economic costs. The data also describe the climatic conditions under tunnels as well as the dynamics of soil nitrate concentration and water tension over time through treatments. Yields, economic benefits and the rates of products with visual defects are presented. In addition, some variables applied exclusively to sweet pepper crops, namely nitrate concentration in petiole sap, growth parameters, abundance of aerial pests and beneficials, incidence of root necrosis, arbuscular mycorrhizal fungi colonization rates and diversity in roots. The field dataset is made publicly available to allow free and easy access for the scientific and professional community to enable analysis and reuse. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Breakthrough: a first-in-class virtual simulator for dose optimization of ACE inhibitors in translational cardiovascular medicine

The renin-angiotensin-aldosterone-systems (RAAS) play a central role in the pathophysiology of congestive heart failure (CHF), justifying the use of angiotensin converting enzyme inhibitors (ACEi) in dogs and humans with cardiac diseases. Seminal studies in canine CHF had suggested that the pharmacological action of benazepril was relatively independent of doses greater than 0.25 mg/kg P.O, thereby providing a rationale for the European labeled dose of benazepril in dogs with CHF. However, most of these earlier studies relied on measures of ACE activity, a sub-optimal endpoint to characterize the effect of ACEi on the RAAS. The objectives of this study were (i) to expand on previous mathematical modeling efforts of the dose-exposure-response relationship of benazepril on biomarkers of the RAAS which are relevant to CHF pathophysiology and disease prognosis; and (ii) to develop a software implementation capable of simulating clinical trials in benazepril in dogs bedside dose optimization. Our results suggest that 0.5 mg/kg PO q12h of benazepril produces the most robust reduction in angiotensin II and upregulation of RAAS alternative pathway biomarkers. This model will eventually be expanded to include relevant clinical endpoints, which will be evaluated in an upcoming prospective trial in canine patients with CHF.

Dose-response of benazepril on biomarkers of the classical and alternative pathways of the renin-angiotensin-aldosterone system in dogs

Angiotensin-converting enzyme inhibitors (ACEI) such as benazepril are commonly prescribed in both humans and dogs with heart disease to mitigate the renin-angiotensin-aldosterone system (RAAS); however, the dose-dependent effects of benazepril on comprehensive RAAS components remain unknown. In this study, nine purpose-bred healthy dogs received three different dosages of oral benazepril (0.125 mg/kg, 0.25 mg/kg, or 0.5 mg/kg) in a randomized crossover design following induction of RAAS activation by consuming a low-sodium diet. Blood samples were collected at serial time intervals after benazepril dosing to measure plasma benazeprilat (active metabolite of benazepril) and serum RAAS biomarkers. Blood pressure and echocardiogram were performed at baseline and after each benazepril administration. Time-weighted averages for RAAS biomarkers for 12 h post-dose and hemodynamic variables were compared between dosing groups using Wilcoxon rank-sum testing. Compared to the lowest dosage of benazepril (0.125 mg/kg), the highest dosage (0.5 mg/kg) resulted in lower time-weighted average values of angiotensin (Ang) II (- 38%, P = 0.004), Ang1-5 (- 53%, P = 0.001), ACE-S (surrogate for ACE activity; - 59%, P = 0.0002), and ALT-S (surrogate for alternative RAAS activity; - 22%, P = 0.004), and higher values of AngI (+ 78%, P = 0.014) and PRA-S (surrogate for plasma renin activity; + 58%, P = 0.040). There were no relevant differences between dosing groups for blood pressure or echocardiographic variables. Knowledge of dose-dependent alterations in biomarkers of the classical and alternative RAAS pathways could help inform clinical trials for dosage optimization in both dogs and humans.

'The Mercury Challenge': feline systolic blood pressure in primary care practice - a European survey

OBJECTIVES

The aim of this study was to collect data from a substantial number of older cats having their systolic blood pressure (SBP) measured in a variety of clinical practices, to describe the findings and assess variables that affected the duration of assessment and the values obtained.

METHODS

An international (European-based) multicentre convenience sample survey of cats ⩾7 years of age attending veterinary clinics and having SBP measured as part of their clinical assessment. Information gathered included details of the cat, concomitant disease(s) or therapies, SBP results, device used, time taken to assess SBP and the demeanor of the cat.

RESULTS

Useable data were available from 8884 cats aged 7-26 years, from 811 clinics across 16 countries. The device used to measure SBP was Doppler in 47.4% and oscillometry in 48.5%. The demeanor of the cat was reported to be calm in 45.7%, anxious in 41.9% and nervous in 8.9%; and the duration of assessment was reported to be <5 mins in 50.4%, 5-10 minutes in 41.7% and >10 mins in 7.9%. Concomitant chronic kidney disease (CKD) was reported in 21.8%, hyperthyroidism in 12.0% or both in 3.1%. The median SBP was 150 mmHg (range 80-310), with 18.6% classified as hypertensive (SBP 160-179 mmHg) and 21.1% as severely hypertensive (SBP ⩾180 mmHg). The measured SBP was significantly affected by the cat's demeanor, duration of SBP assessment, presence of CKD and/or hyperthyroidism, the cat's sex and age, and the presence of concomitant therapy. The duration of SBP assessment was significantly affected by the cat's demeanor.

CONCLUSIONS AND RELEVANCE

In veterinary clinics, SBP can be measured in most cats within a short period of time using either Doppler or oscillometric equipment. The presence of CKD or hyperthyroidism was associated with significantly higher SBP values, and anxious or nervous cats had higher SBP values and took longer to obtain SBP assessments.

Harnessing the Biology of Canine Intestinal Organoids to Heighten Understanding of Inflammatory Bowel Disease Pathogenesis and Accelerate Drug Discovery: A One Health Approach

In a recent issue of the Lancet, the prevalence of Inflammatory Bowel Disease (IBD) was estimated at 7 million worldwide. Overall, the burden of IBD is rising globally, with direct and indirect healthcare costs ranging between $14.6 and $31.6 billion in the U.S. alone in 2014. There is currently no cure for IBD, and up to 40% of patients do not respond to medical therapy. Although the exact determinants of the disease pathophysiology remain unknown, the prevailing hypothesis involves complex interplay among host genetics, the intestinal microenvironment (primarily bacteria and dietary constituents), and the mucosal immune system. Importantly, multiple chronic diseases leading to high morbidity and mortality in modern western societies, including type II diabetes, IBD and colorectal cancer, have epidemiologically been linked to the consumption of high-calorie, low-fiber, high monosaccharide, and high-fat diets (HFD). More specifically, data from our laboratory and others have shown that repeated consumption of HFD triggers dysbiotic changes of the gut microbiome concomitant with a state of chronic intestinal inflammation and increased intestinal permeability. However, progress in our understanding of the effect of dietary interventions on IBD pathogenesis has been hampered by a lack of relevant animal models. Additionally, current in vitro cell culture systems are unable to emulate the in vivo interplay between the gut microbiome and the intestinal epithelium in a realistic and translatable way. There remains, therefore, a critical need to develop translatable in vitro and in vivo models that faithfully recapitulate human gut-specific physiological functions to facilitate detailed mechanistic studies on the impact of dietary interventions on gut homeostasis. While the study of murine models has been pivotal in advancing genetic and cellular discoveries, these animal systems often lack key clinical signs and temporal pathological changes representative of IBD. Specifically, some limitations of the mouse model are associated with the use of genetic knockouts to induce immune deficiency and disease. This is vastly different from the natural course of IBD developing in immunologically competent hosts, as is the case in humans and dogs. Noteworthily, abundant literature suggests that canine and human IBD share common clinical and molecular features, such that preclinical studies in dogs with naturally occurring IBD present an opportunity to further our understanding on disease pathogenesis and streamline the development of new therapeutic strategies. Using a stepwise approach, in vitro mechanistic studies investigating the contribution of dietary interventions to chronic intestinal inflammation and "gut leakiness" could be performed in intestinal organoids and organoid derived monolayers. The biologic potential of organoids stems from the method's ability to harness hard-wired cellular programming such that the complexity of the disease background can be reflected more accurately. Likewise, the effect of therapeutic drug candidates could be evaluated in organoids prior to longitudinal studies in dog and human patients with IBD. In this review, we will discuss the value (and limitations) of intestinal organoids derived from a spontaneous animal disease model of IBD (i.e., the dog), and how it can heighten understanding of the interplay between dietary interventions, the gut microbiota and intestinal inflammation. We will also review how intestinal organoids could be used to streamline the preclinical development of therapeutic drug candidates for IBD patients and their best four-legged friends.

Circulating renin‐angiotensin‐aldosterone system activity in cats with systemic hypertension or cardiomyopathy

Background

Activity of the circulating renin‐angiotensin‐aldosterone system (RAAS) has not been comprehensively characterized in cats with systemic hypertension (SH) or cardiomyopathy (CM), and the effects of furosemide or amlodipine treatment on the RAAS have not been fully evaluated in cats.

Hypothesis/Objectives

To document RAAS activity in cats with SH or CM compared to healthy cats and determine how RAAS profiles change with furosemide or amlodipine treatment.

Animals

Sixty‐six client‐owned cats: 15 with SH (7 amlodipine‐treated, 8 untreated), 17 with advanced CM (7 furosemide‐treated, 10 not furosemide‐treated), and 34 healthy cats.

Methods

Equilibrium concentrations of RAAS peptides and aldosterone were quantified in serum samples by liquid chromatography‐mass spectrometry. Variables were compared between groups using Kruskal‐Wallis analysis with post hoc Holms‐corrected Dunn's testing.

Results

Compared with healthy cats, cats with CM had higher concentrations of angiotensin I, aldosterone, and plasma renin activity (all P < .01), and these differences remained significant (P < .03) after considering subgroups of untreated or furosemide‐treated cats. Compared with healthy cats, untreated cats with SH showed no differences in RAAS biomarkers, whereas amlodipine‐treated cats had higher concentrations of angiotensins I, II, III, IV, and 1‐7, aldosterone, and plasma renin activity (all P < .03). Multivariable analysis determined that furosemide and amlodipine treatments were independent predictors of increased RAAS biomarker concentrations.

Conclusions and Clinical Importance

Cats with CM had increased RAAS activity, whereas cats with untreated SH did not. Furosemide and amlodipine both led to nonspecific activation of both classical and alternative RAAS pathways in cats.

Safety of torasemide in healthy adult dogs administered daily for 26 weeks

Thirty‐two (16 males and 16 females) healthy young beagles were randomly divided into four groups of eight. The control group remained untreated. Torasemide (ISEMID^®, Ceva Santé Animale) was orally administered, once daily, at 0.5 mg/kg from Days 1–5 then 0.25 mg/kg to Day 182, and at three times and five times this dosing regimen in two additional groups. Treated animals (predominantly at the higher dose levels) showed dryness of the oral mucosa, evidence of diuresis, decreased diet consumption, decreased bodyweight gain over the first 3 weeks, increased water consumption, increases in erythrocytes count, haemoglobin, calcium and magnesium, decrease in chloride, phosphorus, potassium and sodium, increases in urine pH, decreases in urine specific gravity and increases in serum aldosterone concentrations. Plasma concentrations of torasemide increased in a dose‐dependent manner and showed no evidence of accumulation. There were also changes to electrocardiogram patterns and the macroscopic and microscopic appearance of the kidney and adrenal glands, but these changes were almost exclusively confined to the over‐dosed groups. In conclusion, torasemide was found to be safe when administered to dogs at 0.25 mg/kg once daily for 26 weeks, and any changes were consistent with its known diuretic effects.

Clinical efficacy of a benazepril and spironolactone combination in dogs with congestive heart failure due to myxomatous mitral valve disease: The BEnazepril Spironolactone STudy (BESST)

Background

The renin‐angiotensin‐aldosterone system (RAAS), when chronically activated, is harmful and RAAS‐suppressive drugs are beneficial in the treatment of congestive heart failure (CHF). Mineralocorticoid receptor antagonists are widely used in the treatment of CHF in people.

Hypothesis/Objectives

To determine if a mineralocorticoid receptor antagonist (spironolactone) is beneficial and safe in CHF due to myxomatous mitral valve disease (MMVD) of varying severity, we hypothesized that, when combined with furosemide, a combination product (S+BNZ) containing the ACE inhibitor (ACE‐I), benazepril, and spironolactone, would be superior to benazepril alone.

Animals

Five hundred and sixty‐nine client‐owned dogs, with MMVD and CHF (ACVIM Stage C) of ≤10‐days' duration.

Methods

After initial stabilization, dogs were randomized into a positive‐controlled, double‐blind, multicenter trial, to receive furosemide plus S+BNZ or furosemide plus benazepril. The primary outcome variable was the percentage of dogs reaching cardiac endpoint before Day 360. Cardiac endpoint was defined as cardiac death or euthanasia, recurrence of pulmonary edema, necessity for nonauthorized cardiac drug(s) or a furosemide dosage >8 mg/kg/d.

Results

A significantly lower percentage of dogs treated with S+BNZ reached the primary outcome variable by Day 360 (OR = 0.56; 95% CI, 0.32‐0.98; P = .04) and risk of dying or worsening from cardiac causes, was significantly reduced (HR = 0.73; 95% CI = 0.59‐0.89, P = .002) vs benazepril alone. Adverse events, potentially associated with treatment, were rare and equal between groups.

Conclusion and Clinical Importance

The combination of S+BNZ is effective, safe, and superior to benazepril alone, when used with furosemide for the management of mild, moderate or severe CHF caused by MMVD in dogs.

The predictive value of clinical, radiographic, echocardiographic variables and cardiac biomarkers for assessing risk of the onset of heart failure or cardiac death in dogs with preclinical myxomatous mitral valve disease enrolled in the DELAY study

OBJECTIVES

To identify the predictive value on time to onset of heart failure (HF) or cardiac death of clinical, radiographic, and echocardiographic variables, as well as cardiac biomarkers N-terminal pro brain natriuretic peptide (NT-proBNP) and cardiac troponin I in dogs with preclinical myxomatous mitral valve disease (MMVD).

ANIMALS

One hundred sixty-eight dogs with preclinical MMVD and left atrium to aortic root ratio ≥1.6 (LA:Ao) and normalized left ventricular end-diastolic diameter ≥1.7 were included.

METHODS

Prospective, randomized, multicenter, single-blinded, placebo-controlled study. Clinical, radiographic, echocardiographic variables and plasma cardiac biomarkers concentrations were compared at different time points. Using receiving operating curves analysis, best cutoff for selected variables was identified and the risk to develop the study endpoint at six-month intervals was calculated.

RESULTS

Left atrial to aortic root ratio >2.1 (hazard ratio [HR] 3.2, 95% confidence interval [95% CI] 1.9-5.6), normalized left ventricular end-diastolic diameter > 1.9 (HR: 6.3; 95% CI: 3.3-11.8), early transmitral peak velocity (E peak) > 1 m/sec (HR: 3.9; 95% CI: 2.3-6.7), and NT-proBNP > 1500 ρmol/L (HR: 5.7; 95% CI: 3.3-9.5) were associated with increased risk of HF or cardiac death. The best fit model to predict the risk to reach the endpoint was represented by the plasma NT-proBNP concentrations adjusted for LA:Ao and E peak.

CONCLUSIONS

Logistic and survival models including echocardiographic variables and NT-proBNP can be used to identify dogs with preclinical MMVD at higher risk to develop HF or cardiac death.

Sun backward gazing method for measuring optomechanical errors of solar concentrators: experimental results

This paper presents the first experimental results obtained with the four cameras backward gazing method for measuring the optomechanical errors of solar concentrating surfaces in operation. It consists in combining the images simultaneously acquired by four cameras placed near the solar receiver in order to reconstruct the slope errors of the mirrors digitally. New algorithms adapted to real acquired images are described. The experiment has been conducted on a sun-tracking heliostat of the experimental solar tower THEMIS with canting error measurement accuracy estimated as 0.2 mrad. The main experimental error sources are analyzed, and possible ways of mitigation are proposed, giving reasonable hope of reaching an ultimate measurement accuracy of 0.1 mrad.

Efficacy of oral torasemide in dogs with degenerative mitral valve disease and new onset congestive heart failure: The CARPODIEM study

Background

Torasemide is a potent loop diuretic with potential to treat congestive heart failure (CHF) in dogs.

Objective

Evaluate the efficacy and safety of torasemide compared to furosemide in dogs with first occurrence of CHF caused by degenerative mitral valve disease (DMVD).

Animals

Three hundred and nineteen dogs with new onset CHF attributable to DMVD.

Methods

Double‐blinded randomized noninferiority study of PO torasemide vs furosemide in addition to standard CHF treatment. The primary efficacy criterion was decreased pulmonary edema and cough and no worsening of dyspnea or exercise tolerance at day 14. Secondary endpoints included clinical response at day 84 and time to death, euthanasia, or premature study withdrawal for cardiac reasons.

Results

Torasemide q24h (n = 161) was noninferior to furosemide q12h (n = 158); percentage of dogs meeting primary efficacy criterion at day 14 was similar between groups (torasemide, 74.4% [95% confidence interval (CI), 66.8%‐81.0%] vs. furosemide, 73.5% [95% CI, 65.7%‐80.4%]; risk ratio [RR], 1.01; 95% CI, 0.89‐1.15; P = .87). Efficacy at day 84 showed similar results (RR, 1.05; 95% CI, 0.88‐1.25; P = .6). Dogs receiving torasemide had a longer time to endpoint and were less than half as likely to experience death, euthanasia, or premature study withdrawal (hazard ratio, 0.36; 95% CI, 0.19‐0.65; P = .001) than dogs receiving furosemide at any time during the study.

Conclusion and Clinical importance

Torasemide was noninferior to furosemide as first line PO treatment for new onset CHF caused by DMVD. Torasemide significantly decreased risk of cardiac‐related death or premature study withdrawal for cardiac reasons compared to furosemide.

Population Pharmacokinetics and Pharmacodynamics Modeling of Torasemide and Furosemide After Oral Repeated Administration in Healthy Dogs

Torasemide is a loop diuretic licensed in dogs for cardiogenic pulmonary oedema. The aim of this pharmacokinetic-pharmacodynamic (PK/PD) study was to define an optimally effective dosage regimen based on preclinical data. In a first study, 5 dogs received once-daily oral torasemide (0, 0.1, 0.2, 0.4, 0.8 mg/kg/day) for 14 days. A second study compared once-daily oral torasemide (0, 0.1, 0.2, 0.3, 0.4 mg/kg/day) to twice-daily furosemide (1, 2, 4, 8 mg/kg/day). For all doses of the second study, 11 dogs received a first day of treatment, followed by a 3 day washout and resumed daily treatment for 10 days (until Day 14). Blood and urine were collected to measure urinary torasemide excretion and plasma torasemide concentrations and daily diuresis and natriuresis. Torasemide PK was linear. After rapid absorption (T_max 0.5–1 h), 61% of the bioavailable torasemide was eliminated unchanged in urine. Diuresis and natriuresis observed with torasemide were similar to the ones obtained after furosemide (daily dose-ratios: 1/20 to 1/10). The average diuresis increased from baseline (220 ± 53 mL/day for 10 kg dogs) to 730 ±120 mL after the first torasemide administration and up to 1150 ± 252 mL after 10 administrations at the highest dose. At higher doses (≥0.3 mg/kg/day), daily diureses after 10 diuretic treatment-days were higher than Day 1 and variable between dogs; in contrast, diureses remained constant over time and less variable for doses up to 0.2 mg/kg/day. Natriuresis peaked after the first day and decreased dramatically after the 2nd treatment-day then stabilized to a value close to baseline, except for 0.4 mg/kg/day. Urinary torasemide excretion predicted pharmacodynamics better than plasma concentrations. The decrease in natriuresis observed was successfully modeled using a resistance mechanism; this is likely due to a reabsorption of sodium which did not seem however to affect the volume of urine excreted. For a daily target diuresis of 460 mL/dog/day in severe pulmonary oedema (net fluid loss 240 mL/dog/day), a computed dose of 0.26 mg/kg/day (3.5 mg/kg/day furosemide-equivalent) was selected for clinical studies. Due to high inter-individual variability in diureses at doses ≥0.3 mg/kg, higher doses should be limited to 3–5 days to avoid supra-clinical effects in high responders.

DELay of Appearance of sYmptoms of Canine Degenerative Mitral Valve Disease Treated with Spironolactone and Benazepril: the DELAY Study

INTRODUCTION

Efficacy of renin-angiotensin-aldosterone system (RAAS) blockade using angiotensin-converting enzyme inhibitors (ACEi) in dogs with preclinical myxomatous mitral valve disease (MMVD) is controversial.

HYPOTHESIS

Administration of spironolactone (2-4 mg q 24 h) and benazepril (0.25-0.5 mg q 24 h) in dogs with preclinical MMVD, not receiving any other cardiac medications, delays the onset of heart failure (HF) and cardiac-related death. Moreover, it reduces the progression of the disease as indicated by echocardiographic parameters and level of cardiac biomarkers N-terminal pro brain natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI).

ANIMALS

184 dogs with pre-clinical MMVD and left atrium-to-aortic root ratio (LA:Ao) ≥1.6 and normalized left ventricular end-diastolic diameter (LVEDDn) ≥1.7.

METHODS

This is a prospective, randomized, multicenter, single-blinded, placebo-controlled study. Primary outcome variable was time-to-onset of first occurrence of HF or cardiac death. Secondary end points included effect of treatment on progression of the disease based on echocardiographic and radiographic parameters, as well as variations of NT-proBNP and cTnI concentrations.

RESULTS

The median time to primary end point was 902 days (95% confidence interval (CI) 682-not available) for the treatment group and 1139 days (95% CI 732-NA) for the control group (p = 0.45). Vertebral heart score (p = 0.05), LA:Ao (p < 0.001), LVEDDn (p < 0.001), trans-mitral E peak velocity (p = 0.011), and NT-proBNP (p = 0.037) were lower at the end of study in the treatment group.

CONCLUSIONS

This study failed in demonstrating that combined administration of spironolactone and benazepril delays onset of HF in dogs with preclinical MMVD. However, such treatment induces beneficial effects on cardiac remodeling and these results could be of clinical relevance.

3071Peptidomimetic targeting of CavBeta2 improves contractility in models of senescence- or genetically (MYBPC3 KI)-induced heart failure

Background

L-type calcium channel (LTCC) trafficking controls LTCC density at T-tubule levels for optimal Excitation-Coupling (EC) and resultant adaptive heart work. In some forms of heart failure (HF), abnormalities in calcium-induced calcium-release have been proposed to arise from alteration of T-tubular dyad architecture (LTCC-RyRs) associated with impaired LTCC density. Recently, the R7W-MP peptide, working as a binder of the LTCC Cavβ2 chaperone, was shown to restore the altered density of LTCC current by both promoting forward and reducing reverse trafficking, which consequently improved cellular calcium homeostasis. Accordingly, R7W-MP improved the impaired cardiomyocyte calcium current density and the reduced Ejection Fraction (EF%) in a pharmacologically-induced diabetes model (STZ mice).

We aimed to investigate further the benefit to improve LTCC trafficking pathway with R7W-MP in a more physiological model of HF (senescent mice) and in a Dilated Cardiomyopathy (DCM) model (HO MYBPC3 targeted KI mutant).

Methods

Senescent male C57Bl/6J mice (26 months) or HO MYBPC3 KI male mice (2 months) were treated with R7W-MP (3 mg/kg/d IP for 3 days). Echocardiographies (echo) were conducted before treatment and 4-hours after the last injection. When applied, Pressure-Volume (PV)-loop investigations were conducted one day post-echo 4 hours following an additional R7W-MP injection.

Results

In senescent mice population, HF was characterized by a midrange ejection fraction (EF%= 43±2 vs 55±1 for young adult mice) associated with enlarged ventricles and decreased cardiac contractility. In contrast to a scrambled peptide (scrP), R7W-MP markedly increased EF% monitored by echo (+38%, 63±3 vs 45±1 for scrP, p≤0.001, n=6–7) without modification of heart rate. EF% improvement was confirmed by PV-loop analysis (78±3 vs 51±4 for scrP (+54%), p≤0.001, n=5), associated with a marked, although not significant, 2.5-fold increase in myocardial contractility [end systolic pressure volume relationship (ESPVR) = 12.1±3.6 vs 4.9±1.3 for scrP, p=0.10, n=4]. Stroke volume, cardiac output and end diastolic volume tended to decrease suggesting an impaired LV filling at this dose regimen. In the DCM model, HF was more severe with a dramatically low EF% (26±1, n=8), impaired myocardial contractility and a pronounced left ventricle enlargement. R7W-MP significantly increased EF% (+17%, reaching 31±1, p≤0.01, n=8) without altering heart rate. Stroke volume was significantly increased by 36% (32±3 vs 24±3 mL at baseline, p≤0.01), without any impairment of diastolic function. All parameters returned to baseline after a 2 week-washout period.

Conclusions

R7W-MP displays potent positive inotrope properties in senescent or DCM mice models. Although further asses tsments of diastolic function are needed (different dosing and duration), these data underline the potential benefit brought by LTCC trafficking modulation to treat severe dilated cardiomyopathy.

The SEISICAT study: a pilot study assessing efficacy and safety of spironolactone in cats with congestive heart failure secondary to cardiomyopathy

INTRODUCTION

The pathophysiology of heart failure involves activation of several neurohormonal systems including the renin-angiotensin-aldosterone system. The mineralocorticoid receptor antagonist spironolactone has been shown to be beneficial in humans and dogs with heart failure. The objective of this pilot study was to investigate the efficacy and safety of spironolactone in cats with heart failure secondary to cardiomyopathy already treated with furosemide and an angiotensin-converting enzyme inhibitor.

ANIMALS

Twenty cats with heart failure due to cardiomyopathy.

METHODS

The study was a double-blind, randomised, placebo-controlled, multicentre clinical study assessing the effect of spironolactone on survival and clinical parameters in cats with heart failure due to cardiomyopathy. The primary end point was mortality, defined as death (spontaneous or by euthanasia) due to cardiac causes.

RESULTS

Twenty cats were enrolled: 9 in the spironolactone group and 11 in the placebo group of which 56% (5/9) and 0% (0/11) completed the 15-month period respectively. At inclusion, differences in systemic blood pressure, body condition score, electrocardiographic abnormalities and LA/Ao ratio suggested that disease may be less severe in the spironolactone group. Twenty-two percent (2/9) of cats in the spironolactone group and 82% (9/11) in the control group reached the primary end point (Fisher's exact test, p = 0.0216). No safety issues were identified in either group.

CONCLUSIONS

This study suggests that spironolactone is well tolerated, and preliminary results support further investigation to evaluate the efficacy of spironolactone in the treatment of cats with cardiac failure due to cardiomyopathy.

Highly efficient end-side-pumped Nd:YAG solar laser by a heliostat-parabolic mirror system

We report a large improvement in the collection and slope efficiency of an Nd:YAG solar laser pumped by a heliostat-parabolic mirror system. A conical fused silica lens was used to further concentrate the solar radiation from the focal zone of a 2 m diameter primary concentrator to a Nd:YAG single-crystal rod within a conical pump cavity, which enabled multipass pumping to the active medium. A 56 W cw laser power was measured, corresponding to 21.1  W/m2 record-high solar laser collection efficiency with the heliostat-parabolic mirror system. 4.9% slope efficiency was calculated, corresponding to 175% enhancement over our previous result.

[The role of nipple-sparing mastectomy in breast cancer: a comprehensive review of the literature]

BACKGROUND

The role of nipple-sparing mastectomy (NSM) for breast cancer is controversial as there is concern regarding its oncological safety and complication rate. We carried out a review of the literature to quantify the incidence of occult nipple malignancy in breast cancer, identify the factors influencing occult nipple malignancy, quantify locoregional recurrence rates and quantify NSM complication rates.

METHODS

A search of the literature was performed using PubMed. Keywords used were "mastectomy", "nipple involvement", "nipple-sparing mastectomy", "skin-sparing mastectomy" "occult nipple malignancy" "occult nipple disease" "breast cancer recurrence". Articles were analyzed regarding incidence of occult nipple malignancy, potential factors influencing the incidence of occult malignancy and recurrence/complications following NSM. The incidence of occult nipple disease was compared between groups using Chi(2) or Fisher's exact tests for categorical variables and Student's t-tests for continuous variables. P values were considered significant<0.05. We identified nearly 30 studies compiling nearly 10 000 cases examining the rate of occult nipple malignancy and 23 studies compiling 2300 cases providing information on the rate of local recurrence after NSM.

RESULTS

The overall rate of occult nipple malignancy was 11.5 %. Primary tumour characteristics influencing occult nipple malignancy were tumour-nipple distance<2cm, grade, lymph node metastasis, lymphovascular invasion, HER2 positive, ER/PR negative, tumour size>5cm, retro-areolar/central location and multicentric tumours. The overall nipple recurrence rate following NSM was 0.9 %, skin flap recurrence rate was 4.2 %. Full and partial thickness nipple necrosis rates were 2.9 % and 6.3 % respectively.

CONCLUSION

NSM for primary breast cancer is appropriate in carefully selected patients. All patients should have retro-areolar sampling. There is strong evidence to suggest that suitable cases are well circumscribed single or multifocal lesions that have a TND>2cm. Tumours should be graded 1-2 and not have LVI, axillary node metastasis or HER2 positivity.

Extensive pure ductal carcinoma in situ of the breast: identification of predictors of associated infiltrating carcinoma and lymph node metastasis before immediate reconstructive surgery

AIM

To identify predictors for infiltrating carcinoma and lymph node involvement, before immediate breast reconstructive surgery, in patients with an initial diagnosis of extensive pure ductal carcinoma in situ of the breast (DCIS).

PATIENTS AND METHODS

Between January 2000 and December 2009, 241 patients with pure extensive DCIS in preoperative biopsy had underwent mastectomy. Axillary staging (sentinel node and/or axillary dissection) was performed in 92% (n = 221) of patients. Patients with micro-invasive lesions at initial diagnosis, recurrence or contralateral breast cancer were excluded.

RESULTS

Respectively 14% and 21% of patients had a final diagnosis of micro-invasive carcinoma (MIC) and invasive ductal carcinoma (IDC). Univariate analysis showed that the following variables at diagnosis were significantly correlated with the presence of either MIC or IDC in the mastectomy specimen: palpable tumor (p = 0.002), high grade DCIS (p = 0.002) and detection of an opacity by mammography (p = 0.019). Axillary lymph node (ALN) involvement was reported in 9% of patients. Univariate analysis suggested that a body mass index higher than 25 (p = 0.007), a palpable tumor (p = 0.012) and the detection of an opacity by mammography (p = 0.044) were associated with an increased rate of ALN involvement.

CONCLUSION

Skin-sparing mastectomy and immediate breast reconstruction (IBRS) has become increasingly popular, especially for patients with extended DCIS of the breast. This study confirmed that extended DCIS is associated with a substantial risk of finding MIC or IDC on the surgical specimen but also ALN involvement. Adjuvant systemic treatment and/or radiotherapy could be indicated for some of these patients after the surgery. Patients should be informed of the rate of 1) complications associated to IBRS that will potentially delay the introduction of systemic or local therapy 2) complications associated to radiotherapy after IBRS.

Abstract P5-14-18: Extended Pure Ductal Carcinoma In Situ of the Breast on Preoperative Biopsies. Prognostic Factors for Infiltrating Carcinoma and Lymph Node Involvement

Introduction: The aim of our study was to identify predictive factors of infiltrating carcinoma and lymph node involvement in patients with an initial diagnosis of extended pure ductal carcinoma in situ (DCIS) of the breast.

Material and Methods: 241 patients diagnosed with extended pure ductal carcinoma in situ (DCIS) underwent treatment at the Institut Curie (2000-2009) consisting of mastectomy with or without immediate breast reconstruction (IMR). Axillary staging (sentinel node and/or standard procedure) was performed in 92% of patients. Patients with micro-invasive lesions at diagnosis, recurrence or contralateral breast cancer were excluded. Differences between groups were analysed by Chi-square or Fisher Exact tests for categorical variables and Student's t-test for continuous variables. Survival analyses were performed using KaplanMeier, with comparisons using the logrank test and hazard ratios estimated using the Cox proportional hazard model. P-values were considered significant when below 0.05.

Results: Respectively 15% and 20%of patients had a final diagnosis of micro-invasive (MIC) and invasive ductal carcinoma (IDC). The median sizes of the DCIS and IDC were respectively 40mm [0-95] and 6mm [2-50] according to final histological assessment. Univariate analysis showed that the following variables at diagnosis were significantly correlated to the presence of either MIC or IDC in the mastectomy specimen; palpable tumor (p=0.02), high grade DCIS (p=0.02), detection of an opacity on mammography (p=0.01). Axillary lymph node involvement was reported in 9% of patients. In univariate analysis a BMI&gt;25 (p=0.007), a palpable tumor (p=0.01), the detection of an opacity (p=0.04) were associated with an increase rate of lymph node involvement. A IMR was performed in 69% of patients. These patients were younger (P&lt;0.00001), thinner (p=0.005), with fewer palpable tumors (p=0.01), and DCIS of lower grades (p=0.03) than patients denied of breast MRI. With a median follow-up of 30 months, 7 patients (3%) experience locoregional recurrence. In univariate analysis a BMI&gt;25 (p=0.06), a palpable tumor (p=0.0004), an opacity (p=0.01) and extended microcalcifications (p=0.02) were associated with a higher rate of loco-regional recurrence. Immediate breast reconstruction was not a significant risk factor for loco-regional recurrence (p=0.31). Conclusion: Extended pure ductal carcinoma of the breast on preoperative biopsies is associated with a substantial risk of finding not only micro-invasive or invasive carcinoma on the mastectomy specimen but also axillary lymph node involvement. Some risk factors have been identified and should be used to exclude patients from immediate reconstruction surgery due to an increased risk of getting adjuvant systemic treatment and radiotherapy. Immediate breast reconstructive surgery was not associated with an increased risk of loco regional recurrence in our series.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-14-18.

Abstract P5-14-12: Management of Phyllodes Breast Tumours: A Review of 165 Cases

Aim:The aim of our study was to examine the treatment and outcome of 165 patients with phyllodes tumours and to review the options for surgical management.

Patients and Methods: This is a retrospective study of 165 patients who presented to the Institut Curie between January 1994 and November 2008 for benign, borderline or malignant phyllodes tumours. Results: The median follow-up was 12.65 months [range 0 to 149.8]. The median age at diagnosis was 44 years [range 17 to 79]. One hundred and sixty patients (97%) had breast conserving treatment, of whom 3 patients (1. 8%) had oncoplastic breast surgery. Younger women had a significantly higher chance of having a benign phyllodes tumor (p = 0.0001) or a tumour of small size (&lt; 0.0001). Histological examination showed 114 benign (69%), 37 borderline (22%) and 14 malignant tumours (9%).

The median tumour size was 30 mm [range 5 to 150]. The tumour margins were considered incomplete (&lt; 10 mm) in 46 out of 165 cases (28%) with 52% revision surgery. Only the tumour grade was a significant risk factor for incomplete tumour margins (p = 0.005). Fifteen patients developed local recurrence (10%) and two, metastases. In univariate analysis, the histological grade (p = 0.008) and tumour size (p=0.02) were significative risk factors for local recurrence with an accentuated risk for borderline tumours and tumours of large size. Similar results were obtained using multivariate analysis (p=0.07)

Conclusion: The mainstay of treatment for phyllodes tumours remains excision with a safe surgical margin, taking advantage breast conserving surgery where amenable. For borderline or malignant phyllodes tumours or in cases of local tumour recurrence, mastectomy and immediate breast reconstruction may become the preferred option.Genetic analysis will potentially supplement classical histological examination in order to improve our management of these tumours. The role of adjuvant treatments is unproven and must be considered on a case-by-case basis.

Aldosterone receptor antagonists--how cardiovascular actions may explain their beneficial effects in heart failure

Historically, aldosterone receptor antagonists (ARA) have been classified as 'potassium sparing diuretics'. However, the positive effect of spironolactone, the most extensively studied ARA, on morbidity and mortality observed in humans suffering cardiac insufficiency could not be explained by the renal effect of the drug alone, and a pivotal clinical study has led to extensive research. Many experimental studies have demonstrated that ARA have previously unexpected beneficial effects on the cardiovascular system including reduction in remodelling of the vascular smooth muscle cells and myocytes and improvement of endothelial cell dysfunction in heart failure. These effects improve vascular compliance and slow down the progression of left ventricular dysfunction and end-organ damage. Furthermore, aldosterone receptor blockade also restores the baroreceptor reflex, improving heart rate variability in heart failure in humans. Some of these effects have been demonstrated in dog models of cardiac disease and so justified further investigation of the potential benefit of ARA in dogs with congestive heart failure (CHF). Positive effects of spironolactone on morbidity and mortality appear to have been seen in studies conducted in dogs suffering from naturally occurring CHF. In addition, eplerenone has been shown to have benefits in canine models of heart failure. The precise mechanisms by which ARA produce these beneficial effects in dogs remain to be determined but this group of drugs clearly provide therapeutic actions out-with their diuretic effects.

Treatment of node-negative infra-centimetric HER2+ invasive breast carcinomas: A joint AERIO/REMAGUS study

517

Background: Trials have shown benefit of adjuvant trastuzumab (TZM) for node-positive (N+) or supra-centrimetric HER-2+ breast carcinomas. There are limited data concerning infra-centimetric HER-2+ invasive breast carcinomas (InfraHER-2). These tumors are being recognized as a high-risk group among all T1a/b tumors. Methods: Retrospective multicenter series from 2000 to 2008 of infra-centimetric HER-2+ invasive breast carcinomas (InfraHER-2). Tumors with ≥80% of ductal carcinoma in situ, multifocal and metastatic tumors were excluded. Results: 96 cases have been evaluated, 75 were node negative (N- InfraHER-2). All patients had surgery. 57% (n = 43) had a sentinel lymph node procedure. 73% (n = 55) had a local irradiation and 36 a tumor bed boost. Nodal irradiation of internal mammar and infra/supraclavicular regions was done in 20% and 17% respectively. 44% (n = 33) had chemotherapy (CT), almost all (31) were associated to TZM. Anthracycline-based (A), taxane-based (T) and A/T combinations were chosen for 54%, 4% and 42% respectively. One patient developed myocardial infarction after A resulting in heart failure; 2 had a transient left ventricular ejection fraction decrease below 50% after TZM. Decision of adjuvant CT was associated (all p < 0.05) with hormonal receptors (HR) negative status, Elston-Ellis grade (EE) 2/3 and high mitotic index (MI) while patients with HR+/low MI tumors were rarely treated (p < 0.001). 32/39 HR+ patients received hormonotherapy (80%); 21 received aromatase inhibitors, 6 tamoxifen and 5 LHRH agonists. With a 25 months median follow-up, there was no invasive recurrence in TZM treated patients. 3 of the 44 patients treated without TZM nor CT (7%) had local or metastatic recurrence including one fatal; they had initially HR- EE 2/3 T1b tumors. Conclusions: In our practice, decision of TZM-based therapy for InfraHER-2 N- tumors is associated with high-risk profile. Indeed, N- InfraHER-2 tumors may have a significant risk of recurrence which could be avoided by adjuvant TZM. Patients with N- InfraHER-2 tumors should be included in HER-2-targeted adjuvant trials.

[Table: see text]

[Rupture of non-communicating rudimentary pregnant uterine horn in a pseudo-unicornuate uterus at 23 weeks of amenorrhea. Case report]

Pregnancy in the rudimentary horn of a unicornuate uterus is an extremely rare form of ectopic gestation associated with a high risk of uterine rupture. We report the case of a pregnancy developed in a non communicating rudimentary horn of a unicornuate uterus complicated by horn rupture at 23 weeks of amenorrhea showing as an acute abdominal pain and massive hemoperitoneum. This patient's uterine abnormality was known before, as this woman has delivered two years before at term a healthy boy by cesarean section. This past pregnancy was located in the normal horn and the non communicating rudimentary horn seemed at this time normal. This uterine malformation is presented with its gynecological and obstetrical entailments as well as methods that could prevent such outcome.

Fertilité après chirurgie cœlioscopique de l'endométriose pelvienne chez des patientes en échec de grossesse

OBJECTIVES

To evaluate fertility outcome after laparoscopic management of endometriosis in an infertile population.

MATERIALS AND METHODS

A retrospective analysis of 64 patients presenting more than one year infertility and a pregnancy-wish associated with minimal to severe endometriotic lesions (stage I to IV according to the revised American Fertility Society (rAFS) classification), treated using laparoscopic surgery in order to remove the entire lesions. We excluded women under 20 years and over 40, as well as those with other infertility factors (tubal non endometriosis-related, hormonal or sperm). Fertility of the remaining 34 patients was studied in relation to endometriosis stage and to pregnancy's mode (spontaneous or induced).

RESULTS

Pregnant women percentage was 65% (22 patients) within a 8.5 months (quartiles: 3; 15.5) [range: 1; 52] post-surgical time, and 86.5% pregnancies issued with a delivery. The rate of pregnant women depended on stage of endometriosis (89% for stages I-II, and 56% for stages III-IV). Sixty percent pregnancies were spontaneous within a 5 months (3; 9) [1; 52] post-surgical time to pregnancy average. When pregnancies were obtained with assisted reproductive techniques, the median post-surgical time to pregnancy was 12 months (9; 22) [2; 31]. Among women with stages I-II endometriosis, the median post-surgical time to pregnancy was 2 months when spontaneous and 20.5 months when induced (P=0.007). In case of stages III-IV endometriosis, pregnancy's delay was 8 and 12 months respectively (P=0.79). Among the 21% women who had had an induced pregnancy failure before surgery, 71% became pregnant and 80% spontaneously. Eighteen patients (53%) had an ovarian endometrioma and 50% of them became pregnant. Among the 4 patients who had colorectal endometriosis requiring colorectal resection, 1 pregnancy was obtained.

CONCLUSIONS

These findings suggest that in a context of more than one year infertility only related to endometriosis, it is reasonable to offer these patients a complete operative laparoscopic treatment of their lesions, which enables 65% of them to be pregnant within a 8.5 months post-surgical median time to pregnancy and spontaneously in 60%. In case of stages I-II endometriosis we suggest a spontaneous pregnancy try during 8 to 12 months before starting induced pregnancy therapeutics instead of stages III-IV endometriosis where induced methods should be used after only 6 or 8 months.

Comparison of cytologic and histologic evaluations of the conjunctiva in the normal equine eye

OBJECTIVE

To describe the cells observed in conjunctival brush cytology (CBC) from normal horses and compare these findings with conjunctival structural histology so as to understand which cells are recovered from CBC.

METHODS

This study was divided into three parts. (1) Conjunctival brush smears were collected from 20 healthy horses on both eyes and a differential count on 300 cells was carried out on May Grünwald-Giemsa (MGG) smears. (2) A similar protocol was used for whole eyes from five horses obtained rapidly after death from a slaughterhouse. The eyes were then assessed for conjunctival histology. (3) Cytobrush smears were collected from five healthy horses. Smears were examined after MGG or periodic acid Schiff (PAS) staining.

RESULTS

The differential cell count showed a majority of deep and intermediate epithelial cells with very few superficial and goblet cells in both eyes. A stratified columnar to cuboidal epithelium was observed on nearly the whole surface of the conjunctiva. A stratified squamous type was observed at the palpebral and bulbar edges. Areas with highest mucus cell indices were found from the nasal to the temporal edge of the equine inferior conjunctiva in the upper palpebral segment near the fornix and in a part of the nasal fornix. In MGG smears no mucus cells were identified; however, they were numerous in PAS smears (22.6% +/- 11) and were mostly cylindrical cells (42.5% +/- 14.4 PAS positive).

CONCLUSIONS

Cytobrush smears in the healthy horse are characterized by a majority of polyhedral and cylindrical cells and a few squamous cells. The cylindrical cells may be mucous cells and probably originate from the main stratified columnar to cuboidal epithelium.

[Ovarian and peritoneal sarcoidosis mimicking an ovarian cancer]

Ovarian and peritoneal sarcoidosis is a very rare condition, with an atypical clinical presentation close to that of ovarian cancer. An erroneous diagnosis could induce a definitive castration. A 38-year-old woman was admitted because of ascites and weight loss. A computerized tomography scan revealed multiple soft tissue nodules in the pelvis, on the ovaries as well as peritoneal deposits. Histological examination after laparoscopic biopsy was indicative of sarcoidosis. Corticosteroids were given to the patient and the symptoms quickly subsided. This case with its clinical presentation is discussed in comparison with previously reported cases.

Échec d'un traitement conservateur d'un placenta accreta

We report a case of placenta accreta left fully in situ during a cesarean section. Postoperative courses were complicated with a thrombosis of the right external iliac artery after embolization and with a pyometra needing n hysterectomy. We discuss the risks of such conservative treatment of a placenta accreta, compared with classical ablation.

Development of an immunomagnetic separation-polymerase chain reaction (IMS-PCR) assay specific for Enterocytozoon bieneusi in water samples

AIMS

Microsporidia have become widely recognized as important human pathogens. Among Microsporidia, Enterocytozoon bieneusi is responsible for severe gastrointestinal disease. To date, no current therapy has been proven effective. Their mode of transmission and environmental occurrence are poorly documented because of the lack of detection methods that are both species-specific and sensitive. In this study, we developed a sensitive and specific molecular method to detect E. bieneusi spores in water samples.

METHODS AND RESULTS

The molecular assay combined immunomagnetic separation (IMS) and polymerase chain reaction (PCR) amplification to detect E. bieneusi spores. A comparison was made of IMS magnetic beads coated with two different monoclonal antibodies, one specific for the Encephalitozoon genus that cross-reacts with E. bieneusi and the other specific only for the E. bieneusi species itself.

CONCLUSIONS

Immunotech beads coated with the antibody specific for E. bieneusi were found to be the most effective combination.

SIGNIFICANCE AND IMPACT OF THE STUDY

The highly specific IMS-PCR assay developed in this study provides a rapid and sensitive means of screening water samples for the presence of E. bieneusi spores.

[Contribution of pelvic floor MRI in the morphological and functional analysis of pre and postoperative levator muscle in patients with genital prolapse]

OBJECTIVES

This study was directed to evaluate the morphological and dynamic aspects of the pelvic floor muscles by the MRI in patients with gynecological prolapse before and after surgery.

MATERIALS AND METHOD

MRI had been made before surgical repair in 13 patients with gynecological prolapse, in 9 of this group MRI had been made after the surgery and the group of control was formed by 4 healthy women. We had used morphologic sequences T2 (TSE) and T1 (SE) and fast sequences T2 (TSE) in different positions: at rest, straining and retention for describe and evaluate the anatomic modification of the levator ani and the changes observed after surgery.

RESULTS

The MRI is able to identify the changes of the levator ani muscles: intrinsic degeneratives lesions, increase of the muscular laxity especially for the puborectalis muscle and the wider of the levator hiatus. After surgical repair, the levator hiatus width and the laxity of the puborectalis muscle are slightly modified during straining.

CONCLUSION

There are lesions in the muscular structure of the pelvic floor in patients with gynecological prolapse. The MRI was able to analyse these lesions very well especially after the use of fast sequences. The MRI is the future for exhaustive and non invasive study of the static pelvic disorders.

Three-dimensional cooling of cesium atoms in a reflecting copper cylinder

We present what is to our knowledge the first observation of spin-polarized atoms cooled within a reflecting cylinder in a high-power medium. A low-pressure vapor of cesium atoms is stored in a glass cell whose volume is 58 cm(3). Cooling laser light (lambda=852 nm) is injected into the cell by optical fibers and is recycled by multiple reflections from the walls of the cylinder. The technique used in this experiment greatly simplifies the generation of laser-cooled atoms. A maximum of 2.5 x 10(8) cold atoms was detected by a time-of-flight technique. The damping of atomic motion has lead to temperatures as low as 3.5muK .

Detection of microsporidia in surface water: a one-year follow-up study

In order to estimate the rate and seasonal variation of Enterocytozoon bieneusi contamination of surface water, sequential samples of water from the River Seine in France were collected during a 1-year period. Each sample (300-600 l) was submitted to sequential filtrations, and the filters were then examined for microsporidia using light microscopy and nested polymerase chain reaction (PCR) for E. bieneusi. Amplified products were hybridized with a E. bieneusi-specific probe. Twenty-five samples of water were analyzed during 1 year. Microscopic examination of stained filters proved unreliable for the identification of spores. Using nested PCR, 16 of 25 specimens were positive (64%). Unexpectedly, E. bieneusi was identified in only one sample by specific hybridization underlining the lack of specificity of ours primers. Nevertheless, using DNA sequence analysis, unknown microsporidia species were identified in eight cases, which had highest scores of homology with Vittaforma corneae or Pleistophora sp. This study shows a low rate of water contamination by E. bieneusi suggesting that the risk of waterborne transmission to humans is limited.

Detection of cryptosporidia and Cryptosporidium parvum oocysts in environmental water samples by immunomagnetic separation-polymerase chain reaction

Cryptosporidium parvum has emerged as one of the most important new contaminants found in drinking water. Current protocols for the detection of cryptosporidia are time-consuming and rather inefficient. We recently described an immunomagnetic separation-polymerase chain reaction (IMS-PCR) assay permitting highly sensitive detection of C. parvum oocysts in drinking water samples. In this study, a second IMS-PCR assay to detect all cryptosporidial oocysts was developed, and both IMS-PCR assays were optimized on river water samples. A comparative study of the two IMS-PCR assays and the classical detection method based on an immunofluorescence assay (IFA) was carried out on 50 environmental samples. Whatever the type of water sample, the discrepancy in C. parvum detection between the IFA and IMS-PCR took the form of IFA-negative/IMS-PCR-positive results, and was caused mainly by the greater sensitivity of IMS-PCR as compared with IFA. Of the 50 water samples, only five tested positive for C. parvum using IMS-PCR, and could constitute a threat to human health. These results show that both IMS-PCR assays provide a rapid (1 d) and sensitive means of screening environmental water samples for the presence of cryptosporidia and C. parvum oocysts.

Pharmacological characterization of muscarinic receptors implicated in rabbit detrusor muscle contraction and activation of inositol phospholipid hydrolysis in rabbit detrusor and parotid gland

In the present study, we evaluated the pharmacological characteristics of the functional muscarinic receptors implicated in rabbit detrusor contraction and coupled to inositol phospholipid turnover in rabbit detrusor and parotid gland. The selectivity of several muscarinic antagonists for detrusor vs. salivary gland muscarinic receptors was also examined. The affinities for the muscarinic m1-, m2- and m3-receptor subtypes were determined using membranes from human cloned receptors expressed in CHO-K1 cells using [3H]-N-methyl scopolamine as a radioligand. Anti-muscarinic activity was determined in isolated rabbit detrusor by measuring the displacement of the contractile response to carbachol, and in rabbit detrusor and rabbit parotid by measuring the displacement of inositol phospholipid hydrolysis (total inositol phosphate accumulation) to carbachol. A significant correlation was found between the potencies to antagonize carbachol-induced rabbit detrusor contraction (pK(B)) and the affinities (pKi) for the m3-receptor subtype (r = 0.93, P = 5 x 10(-6)). Lower, but significant, correlations [0.88 (P = 6.3 x 10(-5)), 0.72 (P = 4.6 x 10(-3))] were obtained with m1- or m2-receptor subtypes, respectively. Each muscarinic antagonist tested displayed similar potency to antagonize carbachol-stimulated inositol phospholipid hydrolysis in rabbit detrusor and parotid (r = 0.96, P = 8 x 10(-3)). A significant correlation was found between the potencies to antagonize carbachol-stimulated inositol phospholipid hydrolysis (pK(B)), determined in rabbit detrusor and rabbit parotid, and the affinities (pK(i)) for the m3-receptor subtype [r = 0.96 (P = 0.01), 0.99 (P = 5 x 10(-5)), respectively] and for the m1-receptor subtype [r = 0.98 (P = 3.5 x 10(-3)), 0.94 (P = 0.02), respectively] but not for the m2-receptor subtype [r = 0.33, 0.57, ns, respectively]. In each in vitro assay, methoctramine (preferential M2 selective antagonist) and pirenzepine (preferential M1 selective antagonist) were slightly potent. We suggest that the muscarinic receptor implicated in the response to carbachol in rabbit detrusor and parotid gland corresponds to the M3-subtype. None of the muscarinic antagonists studied in rabbit tissues displayed preferential affinity for the detrusor.

An immunomagnetic separation polymerase chain reaction assay for rapid and ultra-sensitive detection of Cryptosporidium parvum in drinking water

A sensitive and rapid method was developed to detect Cryptosporidium parvum oocysts in drinking water. This molecular assay combined immunomagnetic separation with polymerase chain reaction amplification to detect very low levels of C. parvum oocysts. Magnetic beads coated with anti-cryptosporidium were used to capture oocysts directly from drinking water membrane filter concentrates, at the same time removing polymerase chain reaction inhibitory substances. The DNA was then extracted by the freeze-boil Chelex-100 treatment, followed by polymerase chain reaction. The immunomagnetic separation-polymerase chain reaction product was identified by non-radioactive hybridization using an internal oligonucleotide probe labelled with digoxigenin. This immunomagnetic separation-polymerase chain reaction assay can detect the presence of a single seeded oocyst in 5-100-1 samples of drinking water, thereby assuring the absence of C. parvum contamination in the sample under analysis.

Mechanisms of the hypoglycemic effects of the alpha2-adrenoceptor antagonists SL84.0418 and deriglidole

The effects of the alpha2-adrenoceptor antagonist SL84.0418 and its two enantiomers, (+) deriglidole and (-)SL86.0714 on glucose and insulin levels were examined in mice and in neonatal streptozotocin-induced diabetic rats. It was recently demonstrated in mouse pancreatic beta-cells that both deriglidole and SL86.0714 inhibit ATP-sensitive K+ channel with similar potency whereas alpha2-adrenoceptors are blocked only by deriglidole. In the present study, we showed, in vivo in mice, that SL84.0418 and deriglidole potently reduced glycemia and antagonized diazoxide-induced hyperglycemia, whereas SL86.0714 and tolbutamide were markedly less potent. In diabetic rats, SL84.0418 and deriglidole (10 mg/kg i.p.) fully normalized glucose tolerance whereas SL86.0714 and tolbutamide only slightly improved it. Five min after deriglidole administration in mice a marked and short lasting rise in insulin levels was observed, followed by a progressive reduction of glycemia. In diabetic rats, insulin and norepinephrine levels rose 15 min after deriglidole administration. Sympathetic outflow blockade by chlorisondamine, beta-adrenoceptor blockade by propranolol or their combination markedly reduced deriglidole-induced rise in insulin levels in a similar manner. Furthermore, in chlorisondamine-treated animals norepinephrine levels were strongly lowered and not modified by deriglidole and propranolol administration. However, in spite of sympathetic outflow and beta-adrenoceptor blockade, a moderate rise in insulinemia was still observed after deriglidole administration. Taken together these data demonstrate that deriglidole is the enantiomer that mediates the antihyperglycemic and insulin secretory effects of SL84.0418. Our study suggests that the major part of deriglidole effects is the consequence of the blockade of prejunctional alpha2-adrenoceptors that have reinforced the release of catecholamines in adrenergic nerve endings and indirectly activated postjunctional beta-adrenoceptors to further potentiate insulin secretion. However, it is also suggested that another undefined mechanism is involved in deriglidole potentiation of insulin secretion.

beta-Lactamase-producing strains in the species Prevotella intermedia and Prevotella nigrescens

A total of 96 strains were collected that included laboratory strains and clinical isolates classified Prevotella intermedia sensu lato and the type strains of the species P. intermedia sensu stricto and Prevotella nigrescens. Susceptibility to amoxicillin and amoxicillin-clavulanic acid was determined by the Etest. PCR-DNA probe assays were used to speciate each strain as P. intermedia sensu stricto or P. nigrescens. By Etest, 71 strains (74%) were susceptible to both amoxicillin and amoxicillin-clavulanic acid with minimum inhibitory concentrations in the 0.016-0.064 microgram/ml range. In contrast, amoxicillin minimum inhibitory concentrations of 25 strains (26%) were in the range of 1.5-96 micrograms/ml with concomitant amoxicillin-clavulanic acid minimum inhibitory concentrations in the low range 0.016-0.38 microgram/ml, indicating a production of beta-lactamase as confirmed by nitrocefin tests. Of these beta-lactamase-producing strains, 20% (5/25) were identified as P. intermedia sensu stricto by the PCR-DNA probe assay and 72% (18/25) as P. nigrescens. Our results provide support for the major role of P. nigrescens in the failure of therapy using beta-lactam antibiotics.

Detection of Bacteroides forsythus by immunomagnetic capture and a polymerase chain reaction-DNA probe assay

The aim of this study was to combine immunomagnetic capture and a polymerase chain reaction (PCR) followed by hybridization with a DNA probe for the detection of Bacteroides forsythus. Magnetic beads were coated with the immunoglobulin G fraction of an antiserum specific for B. forsynthus. Aliquots were incubated with various concentrations of a suspension of B. forsythus or with a suspension containing 16 bacterial species, at a concentration of 10(10) cells/ml, spiked with dilutions of B. forsythus. Beads with bound bacteria were boiled, and the target DNA in the supernatant was amplified to generate a 392-bp PCR fragment specific for B. forsythus. The amplified product was detected by dot-blot hybridization with a digoxigenin-labeled 392-bp probe. The detection limit was determined to be 10 cells/ml using immunocapture on a suspension of B. forsythus and 100 on spiked bacterial suspensions. Subgingival plaque samples were obtained from 39 Bolivian individuals with poor oral hygiene. Each sample was analyzed by the above procedure and by immunofluorescence. The overall prevalence of individuals harboring B. forsythus was 62% by immunofluorescence and 82% by PCR-DNA probe assay. The immunocapture, PCR. DNA-probe procedure should be useful for the detection of B. forsythus, particularly in false-negative samples obtained by less sensitive techniques.

Octanoate metabolism in primary culture of chicken hepatocytes: evidence for high-capacity octanoate esterification

[14C]Octanoate metabolism was measured in chicken primary hepatocytes, as a function of time in culture. [14C]Octanoate was essentially converted to oxidative products (CO2 and ketone bodies) in freshly isolated cells while [14C]palmitate was exclusively esterified in triacylglycerols (TG). In contrast, in cultured cells, [14C] octanoate was exclusively recovered in TG as radiolabeled octanoate (33%), but also as newly synthetised fatty acids mainly palmitate (37%), stearate (18%), oleate (4.4%), decanoate (2.4%), and myristate (2.2%). Therefore, it may be suggested that the enhanced lipogenic conditions induced by culture enhance octanoate flux toward TG synthesis in this model. It is further suggested that chicken hepatocytes in primary culture could be a useful model to study regulatory mechanisms of several lipogenic enzymes.

Comparative alpha-1 adrenoceptor subtype selectivity and functional uroselectivity of alpha-1 adrenoceptor antagonists

We investigated the relevance of selectivity for a given alpha-1-adrenoceptor subtype for in vivo uroselectivity of several alpha-1-adrenoceptor antagonists (alfuzosin, doxazosin, prazosin, tamsulosin, terazosin and 5-Me-urapidil). Comparison of the affinities of these alpha-1-adrenoceptor antagonists at the cloned alpha-1a, alpha-1b and alpha-1d-adrenoceptor subtypes revealed that tamsulosin and 5-Me-urapidil showed selectivity for the alpha-1a subtype. No significant correlations were found between the affinities for alpha-1b or alpha-1d-adrenoceptors and the pK(B) values obtained against phenylephrine-induced contraction of the rabbit prostate in vitro. In contrast, the antagonist potencies in rabbit prostate were correlated (r = 0.89, P < .05) with the pKi values for the alpha-1a-adrenoceptor subtype. However, the pK(B) values were consistently smaller (by 0.6 to 1.9 log unit) than the pKi values for the alpha-1a-adrenoceptor subtype, a result that suggests that the alpha-1-adrenoceptor mediating urethral contractions does not have all the characteristics of the alpha-1a-adrenoceptor. The simultaneous measurement of urethral and arterial pressures in the same conscious male rat allows evaluation of the functional uroselectivity of these antagonists based on their respective effects on both pressures. Dose ranges were selected according to effects on urethral pressure and most antagonists were found effective within the 3 to 100 microg/kg i.v. range. Alfuzosin markedly decreased urethral pressure and either did not decrease blood pressure (10-30 microg/kg) or slightly decreased it at the highest dose tested (100 microg/kg). Doxazosin did not produce sustained reductions in urethral pressure until a dose of 30 microg/kg. Blood pressure was not reduced until 100 microg/kg. Prazosin reduced urethral pressure and blood pressure within the same dose-range whereas terazosin did not decrease urethral pressure at doses that significantly decreased blood pressure (30 and 100 microg/kg). 5-Me-urapidil, an alpha-1a-selective compound did not significantly modify urethral and blood pressure whereas tamsulosin, another alpha-1a-selective compound reduced urethral pressure and blood pressure within the same dose range. In conclusion, in the conscious male rat the functional uroselectivity is not correlated with a selective affinity for the alpha-1a-adrenoceptor subtype.

PCR-DNA probe assays for identification and detection of Prevotella intermedia sensu stricto and Prevotella nigrescens

The purpose of this study was to construct PCR-DNA probe assays specific for Prevotella intermedia sensu stricto and Prevotella nigrescens based on the ability of randomly amplified polymorphic DNA (RAPD) fingerprinting to generate species-specific markers. The strategy included four steps: (i) construction of first-generation DNA probes from a 850-bp RAPD marker for P. intermedia sensu stricto and a 1,300-bp RAPD marker for P. nigrescens, (ii) cloning and sequencing of each RAPD marker, (iii) designing of primer pairs flanking specific internal sequences of 754 bp for P. intermedia sensu stricto and of ca. 1,100 bp for P. nigrescens, and (iv) synthesis (by PCR amplification) and digoxigenin labeling of quantities of DNA probes 754 and ca. 1,100 bp in size. The PCR-DNA probe assays combine either PCR amplification of a 754-bp specific sequence in the genomic DNA of strains of P. intermedia sensu stricto and hybridization with the 754-bp digoxigenin-labeled probe or amplification of a ca. 1,100-bp sequence of P. nigrescens and hybridization with the ca. 1,100-bp probe. Specific hybridization was observed with the amplified DNAs from 25 strains of P. intermedia and 24 strains of P. nigrescens, and no reaction was observed with the PCR products from 20 foreign species. The PCR-DNA probe assays described here should allow a highly specific and sensitive detection of P. intermedia sensu stricto and P. nigrescens in mixed infections.