Evaluation of bronchoalveolar lavage fluid from donkeys using four different cytological stains: A pilot study.

Bronchoalveolar lavage fluid (BALF) cytology is used for the diagnosis of non-infectious lower airway inflammation in equids. Discrepancies have been reported in the differential cell count when different staining methods were used both in humans and horses. The objective of this study was to compare the results of BALF cytology in donkeys using four different staining methods: modified May-Grunwald Giemsa (mMGG), Diff-Quick (DQ), Toluidine blue (TB) and Perls Prussian blue (PPB). Nine healthy Amiata female donkeys were enrolled. The BAL procedure was performed as previously described and pairs of cytocentrifuged BALF slides were stained with each method. No differences between mMGG and DQ were found for macrophages, neutrophils, and eosinophils, while differences were found in mast cell count between DQ vs.TB, but not between mMGG vs. DQ or mMGG vs. TB. Finally, no differences were obtained in the differential count for hemosiderophages comparing mMGG, DQ and PPB. The mMGG appears to be an excellent stain for the identification of all possible cell types, including mast cells in the BALF of donkeys. DQ, if used alone, may lead to inappropriate identification of mast cells. These results are consistent with the literature on BALF staining methods in horses.

Multivariate factor analysis of milk fatty acid composition in relation to the somatic cell count of single udder quarters.

The present study investigated whether the fatty acid composition of milk changes in relation to an increase in the milk somatic cell count (SCC) of separate udder quarters. We investigated the potential of multivariate factor analysis to extract metabolic evidence from data on the quantity and quality of milk of quarters characterized by different SCC levels. We collected data from individual milk samples taken from single quarters of 49 Italian Holstein cows from the same dairy farm. Factor analysis was carried out on 64 individual fatty acids. In line with a previous study on multivariate factor analysis, a variable was considered to be associated with a specific factor if the absolute value of its correlation with the factor was ≥0.60. Seven factors were extracted that explained the following groups of fatty acids or functions: de novo synthesis, energy balance, uptake of dietary fatty acids, biohydrogenation, short-chain fatty acids, very long chain fatty acids, and odd- and branched-chain fatty acids. An ANOVA of factor scores highlighted the significant effects of the SCC level on de novo fatty acids and biohydrogenation. The de novo fatty acid factor decreased significantly with a high level of SCC, from just 10,000 cells/mL, whereas the biohydrogenation factor showed a significantly higher level in quarters with SCC levels greater than 400,000 cells/mL. This statistical approach enabled us to reduce the number of variables to a few latent factors with biological significance and to represent groups of fatty acids with a common origin and function. Multivariate factor analysis could therefore be key to studying the influence of SCC on the lipid metabolism of single quarters. This approach also demonstrated the metabolic differences between quarters of the same animal showing a different level of SCC.

Dose-dependent effect of romifidine on intraocular pressure in clinically healthy buffalo (Bubalus bubalis).

In the present study, changes in intraocular pressure (IOP) associated with romifidine sedation in buffalo were evaluated. Eighteen healthy adult, non-pregnant, buffalo without ocular abnormalities were used in a prospective randomized trial. Buffalo were allocated into three groups (six each). Buffalo in the treated groups received an intramuscular injection (IM) of romifidine at 40 or 50 µg/kg. The control group was administrated an equivalent volume of sterile saline (0.9% NaCl; 0.4 ml/100 kg). Baseline IOP (T0) values were obtained using applanation tonometry. Immediately afterwards, romifidine was administered and IOP values of both eyes were measured at 5, 15, 30, 45, 60, 90, 120, and 180 min post-administration. The pre-administration values (T0) of IOP for both the left and right eyes ranged from 30-36 (mean, 33 ± 1.5) mmHg and 30-35 (mean, 33.7 ± 1.4), respectively. IOP values decreased significantly after administration of both doses of romifidine compared with the placebo (P < 0.01). Compared with the control, the IOP decreased significantly in animals treated with both doses from 5-90 min post-administration in both eyes (P < 0.05). In the right eye, the lowest IOP value in the romifidine treated groups was observed at T30 (21.6 ± 1.0 and 23.3 ± 1.4 mmHg), respectively. In the left eye, the lowest IOP was observed at T60 (22.5 ± 3.0 and 23.3 ± 2.8 mmHg), respectively. In conclusion, romifidine could be recommended as an alternative analgesic in buffalo, especially for ocular affections associated with increased IOP. A dose of 40 µg/kg could be used at a low cost.

Lamellar ordering, droplet formation and phase inversion in exotic active emulsions.

We study numerically the behaviour of a two-dimensional mixture of a passive isotropic fluid and an active polar gel, in the presence of a surfactant favouring emulsification. Focussing on parameters for which the underlying free energy favours the lamellar phase in the passive limit, we show that the interplay between nonequilibrium and thermodynamic forces creates a range of multifarious exotic emulsions. When the active component is contractile (e.g., an actomyosin solution), moderate activity enhances the efficiency of lamellar ordering, whereas strong activity favours the creation of passive droplets within an active matrix. For extensile activity (occurring, e.g., in microtubule-motor suspensions), instead, we observe an emulsion of spontaneously rotating droplets of different size. By tuning the overall composition, we can create high internal phase emulsions, which undergo sudden phase inversion when activity is switched off. Therefore, we find that activity provides a single control parameter to design composite materials with a strikingly rich range of morphologies.

Oral administration of chestnut tannins to reduce the duration of neonatal calf diarrhea.

BACKGROUND: Neonatal calf diarrhea is generally caused by infectious agents and is a very common disease in bovine practice, leading to substantial economic losses. Tannins are known for their astringent and anti-inflammatory properties in the gastro-enteric tract. The aim of this study was to evaluate the effect of the oral administration of chestnut tannins (Castanea sativa Mill.) in order to reduce the duration of calf neonatal diarrhea. Twenty-four Italian Friesian calves affected by neonatal diarrhea were included. The duration of the diarrheic episode (DDE) was recorded and the animals were divided into a control group (C), which received Effydral® in 2 l of warm water, and a tannin-treated group (T), which received Effydral® in 2 l of warm water plus 10 g of extract of chestnut tannins powder. A Mann-Whitney test was performed to verify differences for the DDE values between the two groups. RESULTS: The DDE was significantly higher in group C than in group T (p = 0.02), resulting in 10.1 ± 3.2 and 6.6 ± 3.8 days, respectively. CONCLUSIONS: Phytotherapic treatments for various diseases have become more common both in human and in veterinary medicine, in order to reduce the presence of antibiotic molecules in the food chain and in the environment. Administration of tannins in calves with diarrhea seemed to shorten the DDE in T by almost 4 days compared to C, suggesting an effective astringent action of chestnut tannins in the calf, as already reported in humans. The use of chestnut tannins in calves could represent an effective, low-impact treatment for neonatal diarrhea.

Plasma procalcitonin concentration in healthy calves and those with septic systemic inflammatory response syndrome.

The diagnosis of sepsis in calves is challenging. Blood culture and clinical signs combined with a complete blood count have been used for the diagnosis of sepsis. Recent literature in humans and animal species has been focused on sepsis-specific biomarkers, such as procalcitonin (PCT), that may more accurately and efficiently diagnose sepsis. The aim of this study was to evaluate plasma PCT concentrations in healthy and septic calves. Twenty healthy control calves and 58 sick calves with septic systemic inflammatory response syndrome (SIRS) based on SIRS score and clinical findings were included. Calves with septic SIRS were further divided in septic SIRS survivors (SSS) and non-survivors (SSNS). Plasma PCT concentrations were measured with a commercial ELISA assay for cattle. A receiver operating characteristic curve was used to determine cut-off values and corresponding sensitivity and specificity for the diagnosis of sepsis. Differences in plasma PCT concentration between groups (control vs. SSS vs. SSNS) were evaluated. Plasma PCT concentrations in healthy calves and those with septic SIRS were 33.3pg/mL (0-44.3pg/mL) and 166.5pg/mL (85.9-233.0pg/mL), respectively (P<0.001). The optimal cut-off value to predict septic SIRS was 67.39pg/mL (81.0% sensitivity, 95.0% specificity). Plasma PCT concentrations were 127.4pg/mL (72.2-216.0pg/mL) and 234.3pg/mL (204.5-309.4pg/mL) in the SSS and SSNS subgroups, respectively. Statistically significant differences were found among groups (control vs. SSS and SSNS, P<0.0001; SSS vs. SSNS, P>0.05). These results confirmed an increase in plasma PCT concentrations in calves with septic SIRS, as previously reported in humans and other species.

Effect of housing system on reproductive behaviour and on some endocrinological and seminal parameters of donkey stallions.

Reproductive management of male donkeys employed for artificial breeding has been poorly studied. The aim of this study was to evaluate the effect of housing system, with the animals grouped together in a paddock or kept in individual boxes, on sexual behaviour, cortisol and testosterone concentration and seminal characteristics of adult male donkeys. The study included four Amiata donkey jacks (stallions) from which ejaculates, saliva and blood were collected during two distinct 3 weeks periods, one in the group and one in the box housing system. Time needed for semen collection was shorter when donkeys were kept in paddocks compared to when they were kept in single boxes (14:57 ± 07:27 and 20:52 ± 09:31 min, p < .05). Native semen characteristics were not influenced by housing system, while cooled preservation in an Equitainer® showed that sperm motility parameters were significantly higher during the paddock period compared to the box period. Salivary cortisol was influenced by housing system, both before and 60 min after ejaculation, being statistically higher when donkeys were housed in paddocks. On the contrary, overall and basal testosterone concentrations were significantly higher when animals were kept in boxes. In conclusion, in the present study, good quality semen could be successfully collected from donkeys irrespective of the housing system despite some differences in hormone concentrations.

How swimming affects plasma insulin and glucose concentration in Thoroughbreds: A pilot study.

Low intensity exercise increases insulin-stimulated glucose uptake in skeletal muscle and decreases its plasma concentration. In this study, plasma insulin and glucose concentrations were evaluated 5min before and 5, 15, 25, 35, 45 and 60min after an IV bolus of glucose in 12 Thoroughbreds before and after 1 month of submaximal aquatraining exercise, monitored using heart rate and blood lactate. Plasma glucose concentrations were evaluated using a colorimetric enzymatic method, and plasma insulin concentrations with a solid-phase radioimmunoassay method. Pre-training plasma glucose concentrations at 15, 25 and 35min, area under the glucose curve and peak glucose concentration were significantly higher than post-training values (P<0.05). Baseline pre-training plasma insulin concentrations were significantly lower than in the post-training period, and plasma insulin was significantly higher at 45 and 60min in the pre-training period than the post-training period. These results indicate that aquatraining could improve insulin-glucose metabolism in horses.

Hematological and biochemical findings in pregnant, postfoaling, and lactating jennies.

The aims of this study were to (1) verify if significant changes occur in hematological and biochemical parameters in jennies during the last 2 months of pregnancy and the first 2 months of lactation, and (2) determine any differences with mares. Hematological and biochemical parameters were evaluated in jennies every 15 days during late pregnancy, parturition, and early lactation. The Kolmogorov-Smirnov test, analysis of variance for repeated measurements and Tukey's multiple comparison test as post hoc were applied. The significance level was set at P < 0.05. Statistical analysis showed differences related to time for Red Blood Cells (RBC) count and Hematocrit (HCT), White Blood Cells (WBC) count, platelet count (PLT), total proteins, blood urea, triglycerides and total cholesterol concentrations, aspartate aminotransferase, gamma-glutamyltransferase, creatine-phosphokinase activities, sodium (Na) and potassium (K). RBC and HCT were higher in late pregnancy than at foaling and during lactation. The relative anemia might be due to increased water ingestion because of fluid losses. The WBC count was higher at foaling than during late pregnancy and lactation. This could be related to the release of cortisol and catecholamine during delivery. The PLT trend showed lower values from delivery to the first 2 months of lactation compared to late gestation. Blood urea increased near parturition, and then remained constant during delivery and lactation, which might be due to the high energy demand at the beginning of lactation. Triglycerides and total cholesterol showed a decrease from delivery through the lactation period. Thus, jennies seem to have a similar metabolism of fats to ponies and draft horse mares, characterized by a greater fat content and mobilization than light breed horses. Aspartate aminotransferase activity decreased at parturition and early lactation, probably because of a predominance of anabolic over catabolic processes during pregnancy. Gamma-glutamyltransferase activity was lower at delivery and during lactation than at late gestation. This could be due to a physiological load on the liver in the perinatal period. Gamma-glutamyltransferase activity was always higher than in mares, but within the normal range for adult donkeys. Creatine-phosphokinase decreased near delivery, then was constant from parturition through the first 2 months of lactation. Na decreased during lactation, probably due to an increased renal retention mediated by aldosterone release during pregnancy. K showed the same trend as Na, and concentrations are in line with the species. The higher K during pregnancy may be due to reabsorption by the gut. Total proteins decreased more during the postpartum period and lactation than in the gestational period. In conclusion, our results showed significant changes in hematological and biochemical parameters in jennies during the last 2 months of pregnancy and the first 2 months of lactation and these changes are only partially comparable to mares.

Plasma Procalcitonin Concentration in Healthy Horses and Horses Affected by Systemic Inflammatory Response Syndrome.

BACKGROUND: The diseases most frequent associated with SIRS in adult horses are those involving the gastrointestinal tract. An early diagnosis should be the goal in the management of horses with SIRS. OBJECTIVE: The objective of this study was to evaluate the plasma procalcitonin (PCT) concentration in healthy and SIRS horses to assess differences between the two groups. ANIMALS: Seventy-eight horses (30 healthy and 48 SIRS). METHODS: Prospective in vivo multicentric study. Horses were classified as SIRS if at least 2 of the following criteria were met: abnormal leukocyte count or distribution, hyperthermia or hypothermia, tachycardia, tachypnea. Healthy horses showed no clinical or laboratory signs of SIRS. Plasma PCT concentrations were measured with a commercial ELISA assay for equine species. Results were expressed as mean±standard deviation. T-test for unpaired data was performed between healthy and SIRS group. SIRS group was divided in 4 subgroups and t-test was performed between healthy versus each subgroup. RESULTS: PCT concentrations in healthy and SIRS horses were 18.28 ± 20.32 and 197.0 ± 117.0 pg/mL, respectively. T-test showed statistical differences between healthy versus SIRS group and between healthy versus all subgroups. CONCLUSIONS AND CLINICAL IMPORTANCE: Results showed an increase in PCT concentration in SIRS horses as previously reported in humans and dogs. PCT could be used as a single assay in equine practice for detection of SIRS.

Maternal and neonatal evaluation of derivated reactive oxygen metabolites (d-ROMs) and biological antioxidant potential in the horse.

The aim of the present work was to evaluate derivated reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) in mares and foals to study perinatal oxidative status. A total of 60 animals were included in the present study. Maternal and foal venous blood samples were collected immediately after delivery along with a sample drawn from one of the umbilical arteries, and plasma samples were evaluated for lactatemia, d-ROMs, and BAP. The t test for unpaired data was applied between mares versus umbilical artery blood versus foals, both for d-ROMs and BAP. The Pearson test with two-tailed P value and a confidence interval of 95% was performed between d-ROMs and BAP and between d-ROMs and lactatemia, both for mares and foals. Finally, the t test for unpaired data was performed between fillies and colts. The t test showed differences between mares versus their own foals versus umbilical artery blood but not foals versus. umbilical artery blood, both for d-ROMs and BAP. A positive correlation was found both in mares and foals between BAP and d-ROMs and in mares between lactatemia and d-ROM. No differences in gender were found in BAP concentration. Our data are in line to previous studies performed in women and cattle.

Intracardiac echocardiography in electrophysiology.

Intracardiac echocardiography (ICE) is a recent, invaluable tool which can provide real-time anatomical guidance in electrophysiological procedures. By inserting intravenously an ultrasound probe and advancing it into the heart, various different views can be obtained which allow to better visualize patient anatomy, to guide the placement of electrophysiological catheters, and to detect immediately procedural complications as they occur. In atrial fibrillation ablation, ICE proves particularly useful to achieve a safer trans-septal puncture (especially in the presence of anatomical anomalies of the interatrial septum) and to help to monitor the visualization of the mapping catheters (circular, high density), or the monitoring of the balloons catheter (Cryo, Laser) position. In ventricular tachycardia ablation, on the other hand, ICE allows for continuous correlation between electrophysiological and structural findings (such as wall motion anomalies or changes in echodensity), and helps to ensure correct catheter contact and to position it, particularly around delicate structures such as the aortic cusps. In any procedure, ICE is also useful to immediately detect procedural complications, such as thrombus formation along catheters, or pericardial effusion. Thanks to its real-time morphological information, ICE provides an ideal complement to simple fluoroscopy or to more complex electroanatomic mapping techniques and is set to gain a wider role in a broad range of electrophysiological procedures.

Preclinical pharmacokinetics and metabolism of a potent non-nucleoside inhibitor of the hepatitis C virus NS5B polymerase.

The disposition of compound A, a potent inhibitor of the hepatitis C virus (HCV) NS5B polymerase, was characterized in animals in support of its selection for further development. Compound A exhibited marked species differences in pharmacokinetics. Plasma clearance was 44 ml min-1 kg-1 in rats, 9 ml min-1 kg-1 in dogs and 16 ml min-1 kg-1 in rhesus monkeys. Oral bioavailability was low in rats (10%) but significantly higher in dogs (52%) and monkeys (26%). Compound A was eliminated primarily by metabolism in rats, with biliary excretion accounting for 30% of its clearance. Metabolism was mainly mediated by cyclohexyl hydroxylation, with N-deethylation and acyl glucuronide formation constituting minor metabolic pathways. Qualitatively, the same metabolites were identified using in vitro systems from all species studied, including humans. The low oral bioavailability of compound A in rats was mostly due to poor intestinal absorption. This conclusion was borne out by the findings that hepatic extraction in the rat was only 30%, intraperitoneal bioavailability was good, and compound A was poorly absorbed from the rat isolated intestinal loop, with no detectable intestinal metabolism. Compound A was not an inhibitor of major human cytochrome P450 enzymes, indicating minimal potential for clinical drug-drug interactions. The metabolic clearance of compound A in rat, dog and monkey hepatocytes correlated with the systemic clearance observed in these species. Since compound A was very stable in human hepatocytes, the results suggest that it will be a low clearance drug in humans.

Autoantibody detection in scleroderma patients. Diagnostic and analytical performances of a new coupled particle light scattering immunoassay.

OBJECTIVE: We evaluated the diagnostic and analytical performance of the Coupled Particle Light Scattering technology applied to the detection of anti-topoisomerase I (anti-Scl70) and anti-CENP-B autoantibodies. METHODS: The Scl70 antigen was obtained by recombinant DNA procedures using a prokaryotic expression system; CENP-B was a Baculovirus-expressed recombinant protein. Anti-centromere and anti-Scl70 antibodies were assayed in serum samples from 288 patients, of whom 123 had systemic sclerosis/scleroderma and 165 constituted the control groups (including patients with other connective tissue diseases, viral infections, Lyme disease, and healthy subjects). RESULTS: The sensitivity was 98.8% (confidence interval, 96-101%) for anti-Scl70 and 100% (99.6-100%) for anti-CENP-B; the specificity was 99.0% (98-100%) and 100% (99.9-100%) for anti-Scl70 and anti-CENP-B, respectively. The intra-assay coefficient variations (CV) ranged from 3.8 to 9.2% for anti-Scl70, and from 2.8 to 8.0% for anti-CENP-B. Inter-assay CVs were 8.1 to 12.0% for anti-Scl70, and 4.7 to 10.5% for anti-CENP-B. In 3 patients, coexpression of both antibodies was observed. CONCLUSION: The results of this study demonstrate that the light scattering technology is also applicable to the detection of autoantibodies to intracellular antigens for the diagnosis of autoimmune rheumatic diseases.

Characterization of the hepatitis C virus NS2/3 processing reaction by using a purified precursor protein.

The NS2-NS3 region of the hepatitis C virus polyprotein encodes a proteolytic activity that is required for processing of the NS2/3 junction. Membrane association of NS2 and the autocatalytic nature of the NS2/3 processing event have so far constituted hurdles to the detailed investigation of this reaction. We now report the first biochemical characterization of the self-processing activity of a purified NS2/3 precursor. Using multiple sequence alignments, we were able to define a minimal domain, devoid of membrane-anchoring sequences, which was still capable of performing the processing reaction. This truncated protein was efficiently expressed and processed in Escherichia coli. The processing reaction could be significantly suppressed by growth in minimal medium in the absence of added zinc ions, leading to the accumulation of an unprocessed precursor protein in inclusion bodies. This protein was purified to homogeneity, refolded, and shown to undergo processing at the authentic NS2/NS3 cleavage site with rates comparable to those observed using an in vitro-translated full-length NS2/3 precursor. Size-exclusion chromatography and a dependence of the processing rate on the concentration of truncated NS2/3 suggested a functional multimerization of the precursor protein. However, we were unable to observe trans cleavage activity between cleavage-site mutants and active-site mutants. Furthermore, the cleavage reaction of the wild-type protein was not inhibited by addition of a mutant that was unable to undergo self-processing. Site-directed mutagenesis data and the independence of the processing rate from the nature of the added metal ion argue in favor of NS2/3 being a cysteine protease having Cys993 and His952 as a catalytic dyad. We conclude that a purified protein can efficiently reproduce processing at the NS2/3 site in the absence of additional cofactors.

New coupled-particle light-scattering assay for detection of Ro/SSA (52 and 60 kilodaltons) and La/SSB autoantibodies in connective tissue diseases.

The diagnostic and analytical performance of the coupled-particle light-scattering assay in detecting anti-Ro/SSA autoantibodies (the 60-kDa [Ro60] and the 52-kDa [Ro52] antibodies) and anti-La/SSB autoantibodies was evaluated. The antigens were obtained by recombinant DNA procedures to include the most immunogenic epitopes for each protein by using a prokaryotic expression system. Serum samples from 151 patients with connective tissue diseases and 52 control subjects (including patients with viral infections, patients with Lyme disease, and healthy subjects) were studied. Sensitivities for detection of anti-Ro/SSA and anti-La/SSB were 88.2 and 95.2%, respectively; specificities were 97.6 and 98.1%, respectively. The intra-assay coefficient of variation (CV) ranged from 4.3 to 10.9% for anti-Ro/SSA and from 2.8 to 12.5% for anti-La/SSB; interassay CVs ranged from 6.5 to 13.2% and from 8.2 to 14.5%, respectively. Among the anti-Ro/SSA-positive samples, Ro60 was recognized by 66% of the test sera and Ro52 was recognized by 95% of the test sera. Thirty-four percent of the Ro/SSA-positive sera were reactive only with the Ro52 antigen, indicating that anti-Ro52 is the most common antibody specificity recognized by anti-Ro/SSA autoantibodies. No differences were found between the prevalences of anti-Ro60 and anti-Ro52 in relation to systemic lupus erythematosus or Sjögren's syndrome. The results of the present study indicate that this new immunoassay is an efficient diagnostic tool for the detection of anti-Ro/SSA and anti-La/SSB antibodies in patients with autoimmune disorders.

Reactivity to p52 and CM2 recombinant proteins in primary human cytomegalovirus infection with a microparticle agglutination assay.

We evaluated the reactivities of sera against p52 and CM2 recombinant antigens of human cytomegalovirus (HCMV), coated on microparticles, for the differentiation of primary HCMV infection from an established infection. Two different test formats of the CMV Multiplex Copalis assay were evaluated. The 214 serum samples tested were immunoglobulin M (IgM) positive or equivocal by our reference assay. Reactivities against p52 and CM2 antigens were tested for sera from 37 patients with a well-documented seroconversion within the preceding 3 months (119 serum specimens), 31 patients known to have had a seroconversion at least 8 months earlier (31 serum specimens), and 57 patients without a documented seroconversion (64 serum specimens). The assay had a sensitivity for the detection of a primary infection of 70 or 86% by the first test format and a sensitivity of 88 or 94% by the second test format, according to the criteria used to indicate a primary infection by this test. A good correlation of the results of the assay with our in-house avidity index was found. The specificity of the assay warrants further evaluation. With IgM-positive sera, the assay was not sufficiently specific to make a distinction between a primary infection and an established infection.

Adrenocorticotropic hormone-dependent Cushing's syndrome: sensitivity and specificity of inferior petrosal sinus sampling.

BACKGROUND AND PURPOSE: Determining the cause of Cushing's syndrome can be difficult. Bilateral inferior petrosal sinus (IPS) sampling after ovine corticotropin-releasing hormone (oCRH) stimulation is an established technique for the differentiation of pituitary from nonpituitary sources of adrenocorticotropic hormone (ACTH) production. The purpose of this study was to review our experience to determine the sensitivity and specificity of bilateral IPS sampling. METHODS: Between January 1990 and February 1997, 92 patients underwent 94 IPS sampling procedures. Indications for these patients with Cushing's syndrome included no discrete lesion on MR images or CT scans, a discrete lesion present on images but equivocal peripheral ACTH sampling after oCRH stimulation, and persistent Cushing's syndrome after trans-sphenoidal surgery. RESULTS: IPS sampling yielded six false-negative results and one false-positive result, manifesting an overall sensitivity of 92.2% and a specificity of 90.0% for detection of a pituitary source of ACTH after oCRH stimulation. Microadenoma lateralization by IPS sampling after oCRH stimulation agreed with the surgical location in 70.0% of the patients. The technical success rate of initial (presampling) bilateral IPS catheterization was 93.6%. Two serious complications occurred and consisted of a venous subarachnoid hemorrhage and a lower extremity deep venous thrombosis. CONCLUSION: Bilateral IPS sampling after oCRH stimulation is helpful in the evaluation of ACTH-dependent Cushing's syndrome. False-negative results, however, suggest that the possibility of a pituitary source must still be considered when no response to oCRH is documented. Interpetrosal ACTH gradient alone is not sufficient to lateralize the tumor reliably.

Venous subarachnoid hemorrhage after inferior petrosal sinus sampling for adrenocorticotropic hormone.

Neurologic complications associated with inferior petrosal sinus sampling for adrenocorticotropic hormone in the diagnosis of Cushing syndrome are rare. Previously reported complications include brain stem infarction and pontine hemorrhage. We report a case of venous subarachnoid hemorrhage with subsequent acute obstructive hydrocephalus occurring during inferior petrosal sinus sampling for Cushing syndrome.

Large-scale production of peptides using the solid phase continuous flow method. Part 2: preparative synthesis of a 26-Mer peptide thrombin inhibitor.

A preparative method for the preparation of large peptides is described. An advantageous theoretical weight of peptide/weight of starting resin ratio (tPw/Rw) of about 0.3 was successfully experimented. The esterification of the first amino acid was realized with a racemization of less than 1%. The study of the coupling conditions led to the use of a diluted acylating mixture that allowed a 56% consumption of the amino acid derivatives (percentage use of amino acids) introduced in the synthesis. The cost analysis of the synthesis showed that the recovery of the amino acid derivatives was not worthwhile.