No evidence for a bone phenotype in GPRC6A knockout mice under normal physiological conditions

GPRC6A is a seven-transmembrane receptor mediating signaling by a wide range of L-alpha-amino acids, a signaling augmented by the divalent cations Ca(2)(+) and Mg(2)(+). GPRC6A transcripts are detected in numerous mammalian tissues, but the physiological role of the receptor is thus far elusive. Analogously to the closely related calcium-sensing receptor, GPRC6A has been proposed to function as a metabolic sensor of Ca(2)(+) and amino acids in bone and other tissues. In the present study, we have generated the first GPRC6A knockout mice and studied their phenotype with particular focus on bone homeostasis. The generated GPRC6A knockout mice are viable and fertile, develop normally, and exhibit no significant differences in body weight compared with wild-type littermates. Assessment of bone mineral density, histomorphometry, and bone metabolism demonstrated no significant differences between 13-week-old knockout and wild-type mice. In conclusion, our data do not support a role for GPRC6A in normal bone physiology.

Contractile effects of 5-hydroxytryptamine (5-HT) in the equine jejunum circular muscle: functional and immunohistochemical identification of a 5-HT1A-like receptor

REASONS FOR PERFORMING STUDY

Prokinetic drugs used to treat gastrointestinal ileus in man have equivocal results in horses. In man, prokinetic drugs have 5-hydroxytryptamine4(5-HT4) receptors as their target, but little is known about the 5-HT-receptor subtypes in the equine small intestine.

OBJECTIVE

Functional and immunohistochemical identification of the serotonin receptor subtype(s) responsible for the 5-HT induced contractile response in the equine circular jejunum.

METHODS

Isometric organ-bath recordings were carried out to assess spontaneous and drug-evoked contractile activity of equine circular jejunum. Histological investigations by immunofluorescence analyses were performed to check for presence and localisation of this functionally identified 5-HT receptor subtype.

RESULTS

Tonic contractions were induced by 5-HT in horse jejunal circular muscle. Tetrodotoxin, atropine and NG-nitro L-arginine did not modify this response. A set of 5-HT receptor subtype selective antagonists excluded interaction with 5-HT1B, 1D, 2A, 3, 4 and 7 receptors. The selective 5-HT1A receptor antagonists WAY 100635 and NAN 190 caused a clear rightward shift of the concentration-response curve to 5-HT. The contractile effect of 5-CT, that can interact with 5-HT1A, 1B, 1D, 5 and 7 receptors was also antagonised by WAY 100635, identifying the targeted 5-HT receptor as a 5-HT1A-like receptor. Immunohistology performed with rabbit polyclonal anti-5-HT1A receptor antibodies confirmed the presence of muscular 5-HT1A receptors in the muscularis mucosae, and both longitudinal and circular smooth muscle layers of the equine jejunum.

CONCLUSIONS

Contractile responses in equine jejunal circular smooth muscle induced by 5-HT involves 5-HT1A-like receptors.

Bluetongue virus serotype 8-associated congenital hydranencephaly in calves

Hydranencephaly, the almost complete absence of the cerebral parenchyma, induced by infection with modified live bluetongue virus (BTV) crossing the placenta has previously been reported in sheep and rarely in cattle in the USA and in South Africa. The current study describes 29 cases of hydranencephaly in bovine foetuses and 'dummy' calves up to 3 months of age in Belgium associated with natural BTV serotype 8 infection very early in gestation. Histological examination of the remaining cerebral parenchyma showed moderate to severe atrophy of the neural tissue. The lesions observed support the hypothesis of BTV-induced destruction of precursor cells. However, in several calves a slight infiltration of the walls of venules and arterioles with T lymphocytes (vasculitis) was observed as well, which seems to be responsible for at least some of the lesions. Bluetongue viral RNA was detected in 15 animals using a BTV-specific real-time RT-PCR with a much higher success rate in brain tissues compared with blood and spleen samples. Virus isolation in embryonated eggs was unsuccessful. In conclusion, hydranencephaly in calves can be associated with natural wild-type BTV-8 intra-uterine infection.

A case series of symptomatic intraluminal duodenal duplication cysts: presentation, endoscopic therapy, and long-term outcome (with video)

BACKGROUND

Duodenal duplication cysts are rare congenital anomalies. Symptomatic cases have classically been treated by surgical resection, which can be complex because of the close proximity of the cysts to the papilla.

OBJECTIVE

To describe a series of 8 patients with symptomatic duodenal duplication cysts who were treated endoscopically, with a special focus on the long-term outcome.

DESIGN

Retrospective case series.

SETTING

Three tertiary-care European academic hospitals.

PATIENTS

Eight patients, age 8 to 72 years, were treated endoscopically for symptomatic intraluminal duodenal duplication cysts between 1981 and 2006. Seven patients presented with acute pancreatitis, and one patient presented with jaundice.

INTERVENTION

Endoscopic incision and marsupialization of the cysts was performed by using a variety of endoscopic tools (needle-knife and regular sphincterotomes, cystotomes, and polypectomy snares).

MAIN OUTCOME MEASUREMENTS

Technical success of endoscopic intervention and long-term clinical recurrence of symptoms.

RESULTS

No major complications occurred. All patients remained asymptomatic at a median follow-up of 7.3 years.

LIMITATIONS

Retrospective study; the small number of patients.

CONCLUSIONS

The endoscopic treatment of symptomatic intraluminal duodenal duplication cysts is a safe and effective technique, with excellent long-term results. It represents a minimally invasive alternative to surgical resection and might be considered the preferred therapeutic modality for these cases.

Effects of an adapted intravenous amiodarone treatment protocol in horses with atrial fibrillation

REASON FOR PERFORMING STUDY

Good results have been obtained with a human amiodarone (AD) i.v. protocol in horses with chronic atrial fibrillation (AF) and a pharmacokinetic study is required for a specific i.v. amiodarone treatment protocol for horses.

OBJECTIVES

To study the efficacy of this pharmacokinetic based i.v. AD protocol in horses with chronic AF.

METHODS

Six horses with chronic AF were treated with an adapted AD infusion protocol. The protocol consisted of 2 phases with a loading dose followed by a maintenance infusion. In the first phase, horses received an infusion of 6.52 mg AD/kg bwt/h for 1 h followed by 1.1 mg/kg bwt/h for 47 h. In the second phase, horses received a second loading dose of 3.74 mg AD/kg bwt/h for 1 h followed by 1.31 mg/kg bwt/h for 47 h. Clinical signs were monitored, a surface ECG and an intra-atrial electrogram were recorded. AD treatment was discontinued when conversion or any side effects were observed.

RESULTS

Three of the 6 horses cardioverted successfully without side effects. The other 3 horses did not convert and showed adverse effects, including diarrhoea. In the latter, there were no important circulatory problems, but the diarrhoea continued for 10-14 days. The third horse had to be subjected to euthanasia because a concomitant Salmonella infection worsened the clinical signs.

CONCLUSION

The applied treatment protocol based upon pharmacokinetic data achieved clinically relevant concentrations of AD and desethylamiodarone.

POTENTIAL RELEVANCE

Intravenous AD has the potential to be an alternative pharmacological treatment for AF in horses, although AD may lead to adverse drug effects, particularly with cumulative dosing.

Pharmacokinetics of acyclovir after intravenous infusion of acyclovir and after oral administration of acyclovir and its prodrug valacyclovir in healthy adult horses

The purpose of this study was twofold. The first aim was to evaluate the oral bioavailability and pharmacokinetics (PKs) of acyclovir in horses after intravenous (i.v.) administration and after oral administration of acyclovir and its prodrug, valacyclovir. Second, we aimed to combine these PK data with pharmacodynamic (PD) information, i.e., 50% effective concentrations (EC(50) values) from in vitro studies, to design an optimal dosage schedule. Three treatments were administered to healthy adult horses: 10 mg of acyclovir/kg of body weight delivered as an i.v. infusion over 1 h, 20 mg of acyclovir/kg administered as tablets by nasogastric intubation, and 20 mg of valacyclovir/kg administered as tablets by nasogastric intubation. Total plasma concentrations were measured by a high-performance liquid chromatography method combined with fluorescence detection, while unbound plasma concentrations were determined by liquid chromatography-tandem mass spectrometry. The peak concentration of i.v. acyclovir was approximately 10 mug/ml for both the total and the unbound plasma concentrations. The mean half-life of elimination was between 5.05 h (total concentration) and 11.9 h (unbound concentration). Oral administration of acyclovir resulted in low maximum concentration in plasma (C(max)) and poor bioavailability. A 10-times-higher C(max) and an 8-times-higher bioavailability were achieved with oral administration of valacyclovir. The i.v. administration of 10 mg/kg acyclovir and the oral administration of 20 mg/kg valacyclovir achieved concentrations within the sensitivity range of equine herpesvirus type 1 (EHV-1). The higher bioavailability of valacyclovir makes it an attractive candidate for the prophylactic and/or therapeutic treatment of horses infected with EHV-1. The results from the PK/PD modeling showed that a dosage of 40 mg/kg valacyclovir, administered three times daily, would be sufficient to reach plasma concentrations above the EC(50) values.

Striae treated by a novel combination treatment--sand abrasion and a patent mixture containing 15% trichloracetic acid followed by 6-24 hrs of a patent cream under plastic occlusion

BACKGROUND

Striae are a common cosmetic problem, especially for women. Little has been published about chemical peel treatment of striae.

OBJECTIVE

To recount 5 years experience of striae treated by a novel combination treatment--sand abrasion and a patent mixture containing 15% trichloracetic acid followed by 6-24 h of a patent cream under plastic occlusion.

MATERIALS AND METHODS

Sixty-nine females of various phototypes, aged 14-63 years, were treated at various anatomical sites: abdomen (43), lateral thighs (11), breasts (4), back (3), waist (3) and others (5). Striae of all types: fresh, old, mild and severe, were treated. Average follow up was 18 months.

RESULTS

After 1-8 treatments (median 4.2), appearance of the striae improved by 70%. Results were best in fresher and more superficial striae.

CONCLUSIONS

A novel combination treatment is reported which safely, predictably and effectively improved striae in all skin types.

Expression of Hoxa2 in cells entering chondrogenesis impairs overall cartilage development

Vertebrate Hox genes act as developmental architects by patterning embryonic structures like axial skeletal elements, limbs, brainstem territories, or neural crest derivatives. While active during the patterning steps of development, these genes turn out to be down-regulated in specific differentiation programs like that leading to chondrogenesis. To investigate why chondrocyte differentiation is correlated to the silencing of a Hox gene, we generated transgenic mice allowing Cre-mediated conditional misexpression of Hoxa2 and induced this gene in Collagen 2 alpha 1-expressing cells committed to enter chondrogenesis. Persistent Hoxa2 expression in chondrogenic cells resulted in overall chondrodysplasia with delayed cartilage hypertrophy, mineralization, and ossification but without proliferation defects. The absence of skeletal patterning anomaly and the regular migration of precursor cells indicated that the condensation step of chondrogenesis was normal. In contrast, closer examination at the differentiation step showed severely impaired chondrocyte differentiation. In addition, this inhibition affected structures independently of their embryonic origin. In conclusion, for the first time here, by a cell-type specific misexpression, we precisely uncoupled the patterning function of Hoxa2 from its involvement in regulating differentiation programs per se and demonstrate that Hoxa2 displays an anti-chondrogenic activity that is distinct from its patterning function.

Benign biliary inflammatory pseudotumor mimicking a Klatskin tumor

Most biliary tumors at the liver hilum are malignant and, when possible, require radical surgical resection. However, few rare benign lesions exist, for which the differential diagnosis with malignancy is important in order to avoid aggressive surgical treatment. This is a retrospective case report. We report on two patients suffering from presumed inflammatory pseudotumor of the main biliary convergence, mimicking a Klatskin's tumor. Complete multidisciplinary work-up in a specialized hepatobiliary centre, including tumor markers, imaging studies and FDG-PET were strongly in favor of malignancy. The benign nature of the lesions was only suspected on the natural radiological evolution during the time waiting for surgical resection, with progressive spontaneous disappearance of tumor masses. Therefore, we were able to avoid extensive hepatobiliary surgery in both patients, including performance of an extended right hepatectomy. However, the patients had portal vein embolization as a first step in treating the disease, hopefully with no long-term consequences on patient status and liver function tests. Clinicians should be aware that tumors arising at the hepatic bifurcation are not always malignant, even if it is the most frequent cause. Despite extensive multidisciplinary work-up, there are still persisting difficulties in this differential diagnosis.

Self-expanding metallic stents in benign postoperative biliary strictures: a difficult surgical obstacle?

BACKGROUND/AIMS

To report the hazards of surgical management in patients suffering from benign postoperative biliary strictures (BBS) previously treated with self-expanding metallic stents (SEMS).

METHODOLOGY

Five patients with BBS were treated by SEMS (Wallstent in 3 patients and Gianturco stent in 2) through an endoscopic (2 patients) or a percutaneous transhepatic route (3 patients). Metallic stent obstruction due to intraprosthetic epithelial hyperplasia was observed in all patients, being responsible for severe cholangitis and intrahepatic stones in 3 and 2 patients respectively.

RESULTS

One patient remains free of symptoms but presented with right posterior liver atrophy. Difficult biliary repair was encountered in 3 patients, requiring excision and reconstruction of the main biliary convergence for severely damaged biliary wall and epithelium by metallic stents. One patient with a SEMS extended upward the right secondary biliary divisions required a right hemihepatectomy.

CONCLUSIONS

The surgical management of benign biliary strictures is severely complicated by the presence of metallic stents. Thus, SEMS should not be employed for treating BBS in healthy patients with a low operative risk.

Use of sedation for routine diagnostic upper gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy Survey of National Endoscopy Society Members

BACKGROUND/AIMS

Sedation rates may vary among countries, depending on patients' and endoscopists' preferences. The aim of this survey was to investigate the rate of using premedication for routine diagnostic upper gastrointestinal (UGI) endoscopy in endoscopy societies, members of the European Society of Gastrointestinal Endoscopy (ESGE).

METHODS

We evaluated a multiple-choice questionnaire which was e-mailed to representatives of national endoscopy societies, which are members of the ESGE. The questionnaire had 14 items referring to endoscopy practices in each country and the representatives' endoscopy units.

RESULTS

The response rate was 76% (34/45). In 47% of the countries, less than 25% of patients undergo routine diagnostic UGI endoscopy with conscious sedation. In 62% of the responders' endoscopy units, patients are not asked their preference for sedation and do not sign a consent form (59%). Common sedatives in use are midazolam (82%), diazepam (38%) or propofol (47%). Monitoring equipment is not available 'in most of the endoscopy units' in 46% (13/28) of the countries. Though they were available in 91% of the national representatives' endoscopy units, they are rarely (21%) used to monitor unsedated routine diagnostic UGI endoscopy.

CONCLUSIONS

In about 50% of ESGE-related countries, less than 25% of patients are sedated for routine diagnostic UGI endoscopy. Major issues to improve include availability of monitoring equipment and the use of a consent form.

Solid and Pseudopapillary Tumor of the Pancreas—Review and New Insights Into Pathogenesis

Solid pseudopapillary tumors (SPT) of the pancreas are rare neoplasms that occur mostly in young women. Despite of a low malignant potential, 10% to 15% of the cases have aggressive behavior with metastatic dissemination possibly leading to death. To date, no pathological factor can reliably predict the outcome of these tumours. Galectin-3, a major actor in the carcinogenesis of pancreatic ductal adenocarcinoma, has not been investigated in SPT. The presence of progesterone receptors is frequently reported in SPT, whereas that of estrogen receptor (ER) is unclear. We studied 5 cases of SPT consisting of 4 pancreatic tumors and 1 metastatic case. The morphological distinctive feature of metastatic nodules was the presence of polygonal or spindle cells with pleiomorphic nuclei and high mitotic count exhibiting a diffuse, infiltrative growth pattern. We found a strong expression of galectin-3 in all SPTs, whereas, interestingly, it was lower in metastatic nodules. Conversely, no galectin-3 expression was found in normal pancreatic endocrine cells or in neuroendocrine tumors. We suggest therefore that galectin-3 is a useful marker to distinguish SPT from neuroendocrine tumor, and also indicator of behavior because its low expression is associated with metastatic spreading. Moreover, the presence of galectin-3 in both SPT and pancreatic ducts rises the hypothesis of a posible ductal origin of these tumors. Specific antibodies for anti-ERalpha and anti-ERbeta demonstrated a strong expression of ERbeta whereas ERalpha was not detected. In conclusion, the present study brings the first evidence of the involvement of galectin-3 in SPT but also brought up clues which allowed to reconcile previously conflicting results on the presence of ER.

Intravenous amiodarone treatment in horses with chronic atrial fibrillation

Six horses without underlying cardiac disease were presented because of atrial fibrillation of between 5 and 12 months duration. These horses received an intravenous amiodarone treatment of 5mg/kg/h for 1 h followed by 0.83mg/kg/h for 23h and subsequently 1.9mg/kg/h for 30h. During treatment, clinical signs were monitored and a surface ECG and an intra-atrial electrogram were recorded. Infusion was discontinued when sinus rhythm or side effects occurred. Four horses successfully cardioverted, of which one showed symptoms of hind limb weakness and weight shifting. Two horses did not cardiovert and showed similar side effects. In all horses, side effects disappeared within 6h after termination of treatment. Cardiac side effects, such as pro-arrhythmia, were not seen in any of the horses. Total bilirubin slightly increased in three horses and normalised within four days. It was concluded that amiodarone has the potential to treat naturally occurring chronic atrial fibrillation in horses, although further research is needed to refine the infusion protocol.

A TNF receptor loop peptide mimic blocks RANK ligand-induced signaling, bone resorption, and bone loss

Activating receptor activator of NF-kappaB (RANK) and TNF receptor (TNFR) promote osteoclast differentiation. A critical ligand contact site on the TNFR is partly conserved in RANK. Surface plasmon resonance studies showed that a peptide (WP9QY) that mimics this TNFR contact site and inhibits TNF-alpha-induced activity bound to RANK ligand (RANKL). Changing a single residue predicted to play an important role in the interaction reduced the binding significantly. WP9QY, but not the altered control peptide, inhibited the RANKL-induced activation of RANK-dependent signaling in RAW 264.7 cells but had no effect on M-CSF-induced activation of some of the same signaling events. WP9QY but not the control peptide also prevented RANKL-induced bone resorption and osteoclastogenesis, even when TNFRs were absent or blocked. In vivo, where both RANKL and TNF-alpha promote osteoclastogenesis, osteoclast activity, and bone loss, WP9QY prevented the increased osteoclastogenesis and bone loss induced in mice by ovariectomy or low dietary calcium, in the latter case in both wild-type and TNFR double-knockout mice. These results suggest that a peptide that mimics a TNFR ligand contact site blocks bone resorption by interfering with recruitment and activation of osteoclasts by both RANKL and TNF.

Determination of amiodarone and desethylamiodarone in horse plasma and urine by high-performance liquid chromatography combined with UV detection and electrospray ionization mass spectrometry

A rapid method for the quantification of amiodarone and desethylamiodarone in animal plasma using high-performance liquid chromatography combined with UV detection (HPLC-UV) is presented. The sample preparation includes a simple deproteinisation step with acetonitrile. In addition, a sensitive method for the quantification of amiodarone and desethylamiodarone in horse plasma and urine using high-performance liquid chromatography combined with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) is described. The sample preparation includes a solid-phase extraction (SPE) with a SCX column. Tamoxifen is used as an internal standard for both chromatographic methods. Chromatographic separation is achieved on an ODS Hypersil column using isocratic elution with 0.01% diethylamine and acetonitrile as mobile phase for the HPLC-UV method and with 0.1% formic acid and acetonitrile as mobile phase for the LC-MS/MS method. For the HPLC-UV method, good linearity was observed in the range 0-5 microg ml(-1), and in the range 0-1 microg ml(-1) for the LC-MS/MS method. The limit of quantification (LOQ) was set at 50 and 5 ng ml(-1) for the HPLC-UV method and the LC-MS/MS method, respectively. For the UV method, the limit of detection (LOD) was 15 and 10 ng ml(-1) for amiodarone and desethylamiodarone, respectively. The LODs of the LC-MS/MS method in plasma were much lower, i.e. 0.10 and 0.04 ng ml(-1) for amiodarone and desethylamiodarone, respectively. The LODs obtained for the urine samples were 0.16 and 0.09 ng ml(-1) for amiodarone and desethylamiodarone, respectively. The methods were shown to be of use in horses. The rapid HPLC-UV method was used for therapeutic drug monitoring after amiodarone treatment, while the LC-MS/MS method showed its applicability for single dose pharmacokinetic studies.

Horses on pasture may be affected by equine motor neuron disease

REASONS FOR PERFORMING STUDY

Equine motor neuron disease (EMND) was diagnosed in 3 horses maintained on lush, grass-based pasture. This contrasted with North American studies which identified limited or no access to green herbage as an important risk factor for EMND.

HYPOTHESIS

Grazing horses that have an apparently adequate intake of pasture herbage to meet normal equine vitamin E requirements can develop EMND.

METHODS

Owners of 32 European horses diagnosed with EMND completed a questionnaire regarding intrinsic, managemental, nutritional and environmental factors that could potentially be risk factors for EMND, and also regarding clinical signs, treatments and case outcome. Plasma/serum vitamin E data for these horses were supplied by the veterinarians. No control population was studied.

RESULTS

Thirteen of 32 horses (termed the 'grazing' group) had part- or full-time access to grass-based pasture at the onset of EMND (median duration at pasture 12 h/day, range 3-24 h). Five of these horses were at pasture for at least 235 h/day at the onset of EMND, 2 of which were at pasture for at least 23.5 h/day throughout the year. Despite grazing, all these horses had a low vitamin E status. The remaining 19 horses resembled those cases reported from North America, in that they had no or limited access to pasture.

CONCLUSIONS AND POTENTIAL RELEVANCE

A diagnosis of EMND should not be discounted on the basis that a horse has access, even full-time, to lush grass-based pasture. Inadequate vitamin E intake was probably not the sole cause of either the EMND or the low vitamin E status in the grazing horses; the latter was probably the result of abnormal bioavailability or excessive utilisation of vitamin E.

Role of transcranial magnetic stimulation in differentiating motor nervous tract disorders from other causes of recumbency in four horses and one donkey

Transcranial magnetic stimulation and measurement of the magnetic motor-evoked potentials (MMEPs) in the thoracic and pelvic limbs of four recumbent horses and one recumbent donkey were used to assess the integrity of the descending motor pathways, in order to confirm or exclude a descending motor tract lesion as the cause of the recumbency. In two of the animals abnormal MMEPs were recorded; in one of the horses a lesion along the cervical spinal cord due to a fracture of the fifth cervical vertebra was diagnosed and confirmed by radiography and postmortem examination; in another horse, damage to the peripheral nerves of the left forelimb was diagnosed and confirmed postmortem when a large abscess was found to have been compressing the peripheral nerves at the level of the last cervical vertebra. In the three other animals, normal MMEPs were recorded, and laminitis, rhabdomyolysis and physitis were diagnosed as the causes of the recumbency.

Use of plasma ionized calcium levels and Ca2+ substitution response patterns as prognostic parameters for ileus and survival in colic horses

OBJECTIVE

Hypocalcaemia is a common finding in horses with enterocolitis and severe gastrointestinal disorders. The aims of this study were to investigate in colic horses 1)the parameters related to hypocalcaemia, 2)the influence of hypocalcaemia on outcome and 3)the possible beneficial effect of Ca2+ substitution.

DESIGN

Randomized controlled trial.

SETTING

Intensive care unit.

PATIENTS

One hundred forty-four horses that were admitted with an acute abdomen during a 1.5 year period were enrolled and daily evaluated for clinical criteria and whole blood ionized Ca2+ levels. Colic horses with hypocalcaemia were randomly assigned to receive Ca2+.

INTERVENTIONS

Analysis of heparinised whole blood samples. Horses that were assigned to be treated received 400 mEq Ca2+ diluted in 10L of Ringer's lactate solution every 24 h until low reference range limits were obtained or until death.

MEASUREMENTS AND MAIN RESULTS

88% of all colic patients showed blood ionized Ca2+ levels below the reference range at the time of admission. Multivariable analysis revealed that the presence of reflux, signs of endotoxaemia, increased Packed Cell Volume (PCV), alkalinization of pH and the interaction PCV/pH all predispose colic horses to low ionized Ca2+ levels at the time of admission. The Odds for developing ileus during hospitalization are +/- 11.94 times larger for horses in the "very low" calcaemia interval, in comparison with normocalcaemic horses. The Odds for fatal outcome are respectively +/- 9.82 and 8.33 times larger for horses in the "very low" and "low" calcaemia interval. Ca2+ substitution increased the probability of survival, provided that Ca2+ levels could be normalized. The lack of an upward calcaemia response, despite repetitive Ca2+ substitutions, can be guarded as a poor ominous sign.

CONCLUSIONS

Hypocalcaemia in colic horses is of prognostic relevance both with regard to survival as to the probability of development of ileus during hospitalization. This study shows the importance of routine measurement of ionized calcium levels in colic horses. Moreover, correction of hypocalcaemia seems to improve clinical outcome.

Transient complete atrioventricular block following transvenous electrical cardioversion of atrial fibrillation in a horse

Transvenous electrical cardioversion was attempted in a horse with drug refractory atrial fibrillation. A temporary pacing catheter and two defibrillation catheters were inserted transvenously into the right ventricular apex, the right atrium and the pulmonary artery, respectively. Under general anaesthesia 100, 200, 300 and 360 J monophasic shocks were delivered between both defibrillation catheters but sinus rhythm could not be restored. Immediately after the 200, 300 and 360 J shock, transient third-degree atrioventricular block occurred for a period of, respectively, 15, 40 and 55 s. These periods of profound bradycardia were corrected by temporary right ventricular pacing until spontaneous conduction resumed. It is concluded that temporary right ventricular pacing should be available during electrical cardioversion of atrial fibrillation in horses.

Bile duct carcinoid tumors: an uncommon disease but with a good prognosis?

Carcinoid tumors of the biliary tract are exceedingly uncommon. We report 3 cases of primary carcinoid tumors of the biliary tract, which are compared to the reported patients in the literature and to the patients' data with other types of biliary malignancies in our experience.

SETTING

Retrospective analysis in a single academic institution. From a consecutive series of 79 resected tumors of the biliary tract between 1979 and 2002, 3 patients were found to suffer from primary carcinoid tumors (3.8%). There were 2 males and one female patient, with a mean age of 56 years old (range: 46-73), younger than other malignant biliary cancer cases. Clinical presentation included obstructive jaundice in 2 patients. There were no signs of diarrhea or carcinoid syndrome. Location of the tumor included the extrahepatic bile duct in all patients. Two of these patients had a polypoid tumor obstructing the bile duct. The disease was localized in 2 patients, but with liver metastases in the remaining patient. Final diagnosis was achieved on final pathological examination in 2 patients, but preoperative endoscopic biopsies allowed correct diagnosis of nature and tumor staging by octreotide scintigraphy in one patient. Radical resection was achieved in 2 patients with long-term cure at 8.5 and 9.5 years, respectively. A high-risk patient with a small residual liver metastasis after resection is still alive and disease-free under LAR Octreotide SC administration at 17 months postoperatively. The median survival time for patients suffering from carcinoid tumors was 102 months while it was 33 months for patients suffering from cholangiocarcinomas in our experience. Carcinoid tumors of the biliary tract are exceedingly rare. Preoperative diagnosis is uncommon but possible by endoscopic biopsies. Radical resection seems to be associated with a longer survival than classical cholangiocarcinoma.

Hereditary skeletal muscle diseases in the horse. A review

Since riders nowadays are expecting the highest level of performance from their horses, muscular disorders therefore represent a major problem for the equine athlete. A lot of research has been done to identify muscular disorders and their etiopathogenesis. Both acquired and inherited forms of muscle diseases have been described. In this review only the latter forms will be mentioned. Major signs of all muscle disorders are muscular stiffness, cramping or pain, muscular fasciculations, muscular atrophy and exercise intolerance. Muscle biopsies can help to identify the cause of rhabdomyolysis or muscular atrophy. However, especially in hereditary muscular diseases, a lot of questions are still to be answered. Increasing knowledge of the etiopathogenesis and newer diagnostic tests may lead to a more accurate diagnosis of the individual diseases in future.

Urolithiasis in finishing pigs

Urolithiasis in sows and neonatal pigs is well-known, but information on its occurrence and impact in finishing pigs is sparse. This study reports three outbreaks of urolithiasis in finishing pigs. In one herd, no symptoms were observed, whereas in the other herds the presence of calculi caused obstruction of the urinary tract resulting in death. Using infra-red spectroscopy, the predominant mineral-type found in the uroliths was calcium carbonate (calcite). Only small amounts of calcium oxalate (< 1%) could be detected. A high urinary pH, small abnormalities in the mineral composition of the feed and insufficient drinking water were the most important risk factors identified. To prevent urolithiasis, it is important to ensure adequate water intake, to provide a balanced mineral diet, and to avoid urinary tract infections.

Evaluation of a novel 308-nm monochromatic excimer light delivery system in dermatology: a pilot study in different chronic localized dermatoses

BACKGROUND

Recently, units have been developed that are capable of delivering large fluences of narrowband ultraviolet (UV) B selectively to cutaneous lesions within a reasonable time.

OBJECTIVES

To analyse the efficacy of a novel nonlaser 308-nm monochromatic excimer light (MEL) delivery system in various dermatoses usually treated by narrowband UVB phototherapy.

METHODS

Fifty-four patients with chronic and resistant localized dermatoses were enrolled in a prospective study: 17 with palmoplantar pustular psoriasis, seven with plaque-type psoriasis, four with nail psoriasis, eight with chronic atopic dermatitis of the hands, 10 with chronic nonatopic dermatitis of the hands and eight with alopecia areata. The 308-nm xenon chloride MEL delivery system (Excilite; DEKA, Florence, Italy) was used to produce an average incident dose rate of 50 mW cm(-2) at a tube-to-skin distance of 15 cm and with a maximum irradiating area of 512 cm2. The initial dose was based on multiples of a predetermined minimal erythema dose (MED), and subsequent doses were based on the response to treatment. Treatments were scheduled weekly for a maximum of 10 weeks. Clinical responses were evaluated using photographic documentation and (except for alopecia areata) clinical score.

RESULTS

The MED ranged from 250 to 350 mJ cm(-2) (mean +/- SD 318.2 +/- 28.4). MEL at 308 nm was the most effective for palmoplantar pustular psoriasis with a mean improvement of 79% after a mean of 5.3 treatments and a mean dose of 11.8 MED per treatment. Plaque-type psoriasis was significantly less sensitive to treatment and nail psoriasis demonstrated no benefit from treatment. Chronic palmar atopic dermatitis was cleared in two patients and the mean improvement was 54% as compared with 46% in patients with chronic nonatopic dermatitis of the hands. Four complete regrowths among the eight patients with alopecia were observed after a mean of 5.1 treatments. The percentages of improvement had significantly decreased at the 6-month visit, and only four patients (24%) with palmoplantar pustular psoriasis still demonstrated a significant improvement. Common side-effects included intense erythema and, more rarely, blisters, but these were well tolerated.

CONCLUSIONS

Our preliminary results confirm the efficacy of this novel 308-nm MEL delivery system, which appears to be effective and safe for palmoplantar pustular psoriasis. To a lesser extent, plaque-type psoriasis, chronic atopic and nonatopic dermatitis of the hands and alopecia may also benefit from this treatment.

Endoscopic ultrasound guided fine needle aspiration in biliary and pancreatic diseases: pitfalls and performances

Endoscopic ultrasound guided fine needle aspiration (EUSFNA) has become the most accurate modality for characterization of pancreatic cystic and solid lesions, for differential diagnosis of indeterminate pancreatic masses and for locoregional staging of pancreatic and extrahepatic biliary tumours. EUS-FNA should also be performed in distant lymph nodes, ascites, liver, adrenal and mediastinal metastatic locations. Experienced groups reach a sensitivity over 85% with a 90-100% specificity, a positive predictive value of 98-100%, a negative predictive value of 44-80%, and an accuracy of 75-84% in evaluation of pancreatic masses. Morbidity rate (acute pancreatitis, infection, haemorrhage, perforation) is very low being around 1-2% and risk of peritoneal seeding was shown to be significantly lower than percutaneous CT guided FNA. The performance of this technique is dependent on the endoscopist and cytopathologist experience, the location, size and consistency of the tumour and the number of passes in the lesion. The type of echoendoscope or needle used does not influence the results, whereas it remains debated if presence of the cytopathologist on site might improve FNA performances. These last years, a new liquid-based cytology technique has been developed to process the specimen. Different methods exist to prepare this type of material and all these techniques improve EUS-FNA performance by decreasing the number of inadequate specimens and by increasing the possibility to obtain cell blocks allowing for ancillary techniques such as immunohistochemistry and molecular biology.

Transcranial magnetic stimulation: normal values of magnetic motor evoked potentials in 84 normal horses and influence of height, weight, age and sex

REASONS FOR PERFORMING STUDY

Cervical spinal cord dysfunction is a common problem in equine medicine and the currently available tests give no objective information about the functionality of the nervous tracts. Therefore, transcranial magnetic stimulation (TMS) was performed in 84 healthy horses of different height in order to have an objective measure for the integrity of the descending motor tracts in normal horses.

OBJECTIVES

To obtain reference values for onset latency and peak-to-peak amplitude of magnetic motor evoked potentials (MMEPs) and to evaluate the possible effect of height, age and gender on the neurophysiological measures.

METHODS

All horses were sedated and stimulated transcranially by using a magnetic coil placed on the forehead. The stimulator triggered the sweep of an electromyogram machine that recorded MMEPs bilaterally from needle electrodes in the extensor carpi radialis and cranial tibial muscles. In that way, it was possible to measure latency between stimulus and onset of response.

RESULTS

A significant difference was found between recordings made in the fore- and hindlimbs; MMEPs recorded in the front legs had a shorter onset latency and higher peak-to-peak amplitude. Mean +/- s.d. normal values for onset latency of 19.32 +/- 2.50 and 30.54 +/- 5.28 msecs and peak-to-peak amplitude values of 9.54 +/- 3.73 and 6.62 +/- 3.62 mV were obtained for extensor carpi radialis and cranial tibial muscles, respectively. The left-to-right difference in onset latency and peak-to-peak amplitude was not significant. In the same horse, differences up to 0.82 and 1.53 msecs for the extensor carpi radialis and cranial tibial muscles, respectively, lie within the 95% confidence limit and are considered normal. In contrast to onset latency, peak-to-peak amplitude showed a very large intra- and interindividual variability, even in the same muscle. To reduce the variability and predict normal values of new individual cases, influence of height, weight, age and sex on the MMEPs were determined. No significant effects of sex were observed on onset latency and peak-to-peak amplitude. The age of the horse had only a small but significant effect on peak-to-peak amplitude, with larger responses in older horses. Height at the withers and weight of the horse, parameters that strongly correlate with the size of the horse, had an important significant influence on onset latency but not on peak-to-peak amplitude. The age of the horse and height at the withers were used to predict peak-to-peak amplitude and onset latency, respectively, in normal horses.

CONCLUSIONS AND POTENTIAL RELEVANCE

TMS is an excellent addition to the few tools we have for noninvasive imaging of the equine nervous system. Magnetically evoked potentials are highly reproducible and recent advances suggest that the applications of TMS in horses will continue to grow rapidly.

Influence of a lipase inhibitor on gastric sensitivity and accommodation to an orally ingested meal

BACKGROUND

Intraduodenal administration of lipids, through lipid digestion and release of cholecystokinin (CCK), induces viscero-visceral reflexes that affect gastric tone and sensitivity. It is unclear whether the same mechanisms control gastric function after an orally ingested meal.

AIM

To evaluate the effect of orlistat, a selective lipase inhibitor, on gastric response to an orally administered meal.

METHODS

Eighteen healthy volunteers participated in this study. They were treated for 5 days with orlistat (120 mg) or placebo t.d.s. in a double-blind randomized crossover design. During treatment, all subjects underwent a gastric barostat study, measurement of plasma CCK levels and a satiety drinking test.

RESULTS

Although CCK plasma levels were significantly decreased, pre-treatment with orlistat failed to affect gastric compliance (72 +/- 6 mL/mm Hg and 64 +/- 6 mL/mm Hg, NS), gastric sensitivity (discomfort threshold 12.2 +/- 0.6 mm Hg vs. 10.9 +/- 0.6 mm Hg above minimal distending pressure, NS) or gastric accommodation (172 +/- 41 mL vs. 206 +/- 49 mL, NS) to an orally ingested meal. Furthermore, orlistat pre-treatment had no significant effect on the amount of calories ingested during a satiety drinking test (1329 +/- 88 kcal vs. 1217 +/- 115 kcal, NS).

CONCLUSION

Administration of a lipase inhibitor does not affect gastric compliance, sensitivity to distension and accommodation to an orally ingested meal, and does not influence meal-induced satiety.

Treatment and follow-up of clinical cyathostominosis in horses

The results of the treatment with moxidectin or ivermectin of 20 horses with clinical cyathostominosis were studied during a 3-week observation period. Both treatments were effective in completely eliminating larvae from the faeces within 1 or 2 weeks, but no significant improvement in body weight or clinical parameters could be demonstrated over the observation period. The poor short time results of the treatment support the need for an adequate prevention of cyathostominosis in horses.

Ultrasound-guided biopsy as a diagnostic aid in three horses with a cranial mediastinal lymphosarcoma

An ultrasound examination of the thorax of three horses which were performing poorly or had mild signs of colic showed that they had a cranial mediastinal mass and a pleural effusion. A cytological examination of the pleural fluid showed that it did not contain neoplastic cells. A histological examination of an ultrasound-guided core biopsy of the cranial mediastinal mass showed that in each of the three horses it was a lymphosarcoma.

Requirements for specific binding of low affinity inhibitor fragments to the SH2 domain of (pp60)Src are identical to those for high affinity binding of full length inhibitors

Results from a novel approach which uses protein crystallography for the screening of a low affinity inhibitor fragment library are analyzed by comparing the X-ray structures with bound fragments to the structures with the corresponding full length inhibitors. The screen for new phospho-tyrosine mimics binding to the SH2 domain of (pp60)src was initiated because of the limited cell penetration of phosphates. Fragments in our library typically had between 6 and 30 atoms and included compounds which had either millimolar activity in a Biacore assay or were suggested by the ab initio design program LUDI but had no measurable affinity. All identified fragments were located in the phospho-tyrosine pocket. The most promising fragments were successfully used to replace the phospho-tyrosine and resulted in novel nonpeptidic high affinity inhibitors. The significant diversity of successful fragments is reflected in the high flexibility of the phospho-tyrosine pocket. Comparison of the X-ray structures shows that the presence of the H-bond acceptors and not their relative position within the pharmacophore are essential for fragment binding and/or high affinity binding of full length inhibitors. The X-ray data show that the fragments are recognized by forming a complex H-bond network within the phospho-tyrosine pocket of SH2. No fragment structure was found in which this H-bond network was incomplete, and any uncompensated H-bond within the H-bond network leads to a significant decrease in the affinity of full length inhibitors. No correlation between affinity and fragment binding was found for these polar fragments and hence affinity-based screening would have overlooked some interesting starting points for inhibitor design. In contrast, we were unable to identify electron density for hydrophobic fragments, confirming that hydrophobic interactions are important for inhibitor affinity but of minor importance for ligand recognition. Our results suggest that a screening approach using protein crystallography is particularly useful to identify universal fragments for the conserved hydrophilic recognition sites found in target families such as SH2 domains, phosphatases, kinases, proteases, and esterases.

Polyclonal versus monoclonal ELISA for the determination of fecal elastase 1: diagnostic value in cystic fibrosis and chronic pancreatic insufficiency

BACKGROUND

Several clinical studies have evaluated the diagnostic efficiency of fecal elastase 1 (FE1) determination using monoclonal antibodies (ScheBo-Tech, Wettenberg, Germany). We report the results of the comparison of this method with a polyclonal based assay (BioServ AG, Rostock, Germany).

METHODS

We collected single spot samples from two groups of patients. The group of adults included 13 healthy subjects (HS), 12 patients with non-pancreatic gastrointestinal disease (NPGD), 26 with chronic pancreatitis with presence of calcification (CCP) and 14 without calcification (NCP). The group of children included 17 cases of cystic fibrosis (CF) and 21 controls (CO). After a common extraction, both assays were performed as recommended by the manufacturers.

RESULTS

Both tests showed a statistically significant difference between patients with normal pancreatic function and patients with pancreatic disorders. Neither showed a significant difference between HS and NPGD.

CONCLUSIONS

Although a statistical difference was found between the two methods for the normal groups (HS and CO), both kits are suitable for the detection of severe pancreatic insufficiency either in adult patients or in children. However, caution should be taken in case of patients with liquid stool specimens.

Standardization of transcranial magnetic stimulation in the horse

The influence of coil position on the peak-to-peak amplitude and onset latency of transcranial magnetic motor evoked potentials (MMEPs) in the extensor carpi radialis and cranial tibial muscles of horses was evaluated. Seven different stimulating coil positions were obtained by constructing a frame on the forehead. Two stimulation intensities (80% and 100% of maximal stimulator output) and two different coil currents (clockwise and counter-clockwise) were tested. For both recording sites MMEPs with the shortest onset latency and the largest peak-to-peak amplitude were detected when the coil was placed in the median of the forehead. There was no significant difference between left and right side recordings. The direction of the current flow in the coil had no influence on the onset latency of the MMEPs.

Application of an alkyl-diol silica precolumn in a column-switching system for the determination of meloxicam in plasma

The group of LiChrospher alkyl-diol silica (ADS) phases that make part of the unique family of restricted-access materials, have been developed as special packings used in the liquid chromatographic integrated sample processing of biofluids. The advantage of these phases lies in the possibility of direct injection of untreated plasma. An on-line elimination of the protein matrix is achieved with a quantitative recovery together with an on-column enrichment. The present method describes a hand-operated on-line switching high-performance liquid chromatographic system for the determination of meloxicam. Spiked plasma samples were introduced on the ADS precolumn using a 0.05 M phosphate buffer, pH 6.0. After washing with the buffer the ADS column was backflushed with the mobile phase 0.05 M phosphate buffer-30% (v/v) acetonitrile (ACN)-25 mM t-butylamine (TBA) at a pH of 7.0, thus transferring the analyte to the analytical column LiChrocart 125-4 LiChrospher RP-8. The eluent was monitored by a UV-detector set at 364 nm. The developed column-switching method is fully applicable to plasma injections.

Transcranial magnetic stimulation: review of the technique, basic principles and applications

Transcranial magnetic stimulation is rapidly developing as a powerful, non-invasive tool for studying the descending motor tracts in humans. The applications of the test in animals are for the moment restricted to small animals. However, this non-invasive, sensitive and painless technique appears promising as a test of motor tract function in horses where the neurological examination is mainly restricted to clinical evaluation and some ancillary tests, such as radiography, cerebrospinal fluid analysis and electromyography. In this review, we want to discuss the history, basic principles, technique and applications of transcranial magnetic stimulation in humans and small animals and indicate the possibilities for its use in horses. Since the great portion of this review is based on human studies, it is worthwhile to mention that the reports being described are from humans unless otherwise specified.

Influence of detomidine and buprenorphine on motor-evoked potentials in horses

Horses need to be sedated before they are investigated by transcranial magnetic stimulation because of the mild discomfort induced by the evoked muscle contraction and the noise of stimulation. This paper describes the influence of a combination of detomidine (10 microg/kg bodyweight) and a low dose of buprenorphine (2.4 microg/kg) on the onset latency and peak-to-peak amplitude of magnetic motor-evoked potentials in normal horses. There were no significant differences between measurements of these parameters made before the horses were sedated and measurements made 10 and 30 minutes after the drugs were administered.

Percutaneous puncture technique for treating persistent retropharyngeal lymph node infections in seven horses

Between 1999 and 2001, seven horses with fever, dysphagia and a history of chronic upper respiratory tract infection lasting between three weeks and three months were examined. They had been treated unsuccessfully with a variety of antibiotics for three to four weeks. A deep abscess in a retropharyngeal lymph node was diagnosed in each case by clinical examination, endoscopy and echographic examination of the retropharyngeal region. The infected retropharyngeal lymph node of each horse was punctured with a spinal needle under ultrasound guidance. Pus was aspirated from four of the horses, and their abscesses were then rinsed with 0.9 per cent saline solution, and antibiotics (sodium ceftiofur or penicillin) were injected. In the other three horses the pus was too viscous to be aspirated, and the enlarged lymph node was opened along the tract of the needle and rinsed with chlorhexidine. All the horses were treated with penicillin for two weeks and in six of them the clinical signs gradually disappeared. The other horse continued to show fever and the penicillin treatment was continued for another 10 days, after which the signs gradually disappeared over a period of two months.

Persistent decreased plasma cholecystokinin levels in celiac patients under gluten-free diet: respective roles of histological changes and nutrient hydrolysis

Celiac disease is associated with impaired cholecystokinin (CCK) release. The mechanism by which CCK release is impaired is poorly understood and seems to be related to the mucosal atrophy or to decreased stimulation due to reduced intraduodenal nutrient hydrolysis. The aims of our study were to evaluate basal and postprandial CCK in celiac patients presenting with distinctive types of mucosal lesions (normal, infiltrative and atrophic), and to study the role of protein hydrolysis on CCK release. Plasma CCK was measured in 20 celiac patients (normal mucosa: n=6; infiltrative type: n=6; atrophic type=8) and 9 controls, before and after ingestion of a polymeric or a semi-elemental meal. Significant decreases in basal CCK plasma (B 0.6 [95% CI, 0.3-1.3] pmol/l; p<0.003) and postprandial CCK area under curve (AUC 34 [19-61] pmol/l x 120 min, p<0.0001) were observed in patients with an atrophic mucosa compared with treated patients (B 1.6 [1.0-2.4] pmol/l, AUC 267 [172-414] pmol/l x 120 min) or healthy volunteers (B 1.0 [0.7-1.4] pmol/l, AUC 186 [131-264] pmol/l x 120 min). A significant defective CCK release was also observed in patients with an infiltrative type: B 0.4 [0.2-0.7] pmol/l and AUC 56 [31-101] pmol/l x 120 min; p<0.0001. Administration of a semi-elemental diet did not correct the defective CCK release. In conclusion, the decreased CCK levels observed in celiac patients are not strictly related to the mucosal atrophy but rather to the lymphocytic infiltrate. Administration of a predigested meal did not correct the impaired CCK release. Some inhibitory mechanism could be involved in the CCK cell dysfunction observed in celiac patients presenting with lesser degrees of disease activity.

Implantation of a dual-chamber, rate-adaptive pacemaker in a horse with suspected sick sinus syndrome

A five-year-old gelding suffered syncope at the end of a period of exercise. A 24-hour electrocardiogram recording revealed intermittent pauses in the sinus rhythm of up to 10 seconds, indicating sinus node disease; the pauses occurred repeatedly, particularly after exercise. A dual-chamber, rate-adaptive pacemaker was successfully implanted, which prevented excessive postexercise bradycardia and syncope, and allowed the horse to return to work.