Histological and Immunological Description of the Leishmanin Skin Test in Ibizan Hounds.

The leishmanin skin test (LST), a delayed-type hypersensitivity (DTH) reaction to Leishmania infantum, can specifically identify dogs that have made a cell-mediated immune response to L. infantum infection. The Ibizan hound appears to be more resistant to L. infantum infection than other breeds of dog. The aim of this study was to describe the histological and immunohistochemical changes induced by the LST in Ibizan hounds living in an area highly endemic for leishmaniosis. The majority of dogs were apparently healthy, lacked serum antibody to L. infantum and blood parasitaemia, but had marked specific interferon gamma production after in-vitro blood stimulation with L. infantum. Leishmanin (3 × 108 killed promastigotes of L. infantum/ml) was injected intradermally and biopsy samples were obtained from a positive reaction at 72 h from nine Ibizan hounds. A moderate to intense, perivascular to interstitial dermatitis and panniculitis characterized the inflammatory response at the injection site. In addition, three samples had diffuse inflammation in the deep dermis and panniculus. Oedema and necrosis were present in the deep dermis and panniculus. Congestion and haemorrhage were observed in five biopsies. T lymphocytes (CD3+) and large mononuclear cells (lysozyme-) were the most prevalent cells. CD3+ cells were significantly more numerous than CD20+ B cells and lysozyme+ cells. B cells were sparsely distributed, especially in the deep dermis and panniculus. Rare neutrophils and macrophages (lysozyme+) were observed with few eosinophils. Toll-like receptor (TLR)-2 protein was expressed in large mononuclear cells mainly located in the superficial dermis. Leishmania immunohistochemistry was negative and quantitative polymerase chain reaction was positive in all cases. The intradermal injection of killed L. infantum promastigotes in Ibizan hounds causes similar histological and immunohistochemical findings to those described for human subjects and are indicative of a DTH response. Moreover, TLR2 protein is expressed in inflammatory cells similar to findings in clinically affected skin biopsy samples.

Canine Leishmaniasis Progression is Associated with Vitamin D Deficiency.

The relationship between vitamin D deficiency and the risk of suffering from a plethora of health disorders, ranging from autoimmune processes to infectious diseases has been widely described. Nonetheless, the potential role of vitamin D in visceral leishmaniasis remains uncharacterized. In the Mediterranean basin, where the dog is leishmania's main peri-domestic reservoir, control measures against the canine disease have shown beneficial effects on the incidence of human leishmaniasis. In this study, we measured the vitamin D levels in serum samples from a cohort of 68 healthy and disease dogs from a highly endemic area and we have also studied the relationship of these levels with parasitological and immunological parameters. The sick dogs presented significantly lower (P < 0.001) vitamin D levels (19.6 ng/mL) than their non-infected (31.8 ng/mL) and the asymptomatic counterparts (29.6 ng/mL). In addition, vitamin D deficiency correlated with several parameters linked to leishmaniasis progression. However, there was no correlation between vitamin D levels and the Leishmania-specific cellular immune response. Moreover, both the leishmanin skin test and the IFN-γ levels displayed negative correlations with serological, parasitological and clinical signs. Further studies to determine the functional role of vitamin D on the progression and control of canine leishmaniasis are needed.

Diagnostic efficacy of SonoVue, a second generation contrast agent, in the assessment of extracranial carotid or peripheral arteries using colour and spectral Doppler ultrasound: a multicentre study.

The purpose of this study was to demonstrate the improvement in diagnostic quality and diagnostic accuracy of SonoVue microbubble contrast-enhanced ultrasound (CE-US) versus unenhanced ultrasound imaging during the investigation of extracranial carotid or peripheral arteries. 82 patients with suspected extracranial carotid or peripheral arterial disease received four SonoVue doses (0.3 ml, 0.6 ml, 1.2 ml and 2.4 ml) with Doppler ultrasound performed before and following each dose. Diagnostic quality of the CE-US examinations was evaluated off-site for duration of clinically useful contrast enhancement, artefact effects and percentage of examinations converted from non-diagnostic to diagnostic. Accuracy, sensitivity and specificity were assessed as agreement of CE-US diagnosis evaluated by an independent panel of experts with reference standard modality. The median duration of clinically useful signal enhancement significantly increased with increasing SonoVue doses (p< or =0.002). At the dose of 2.4 ml of SonoVue, diagnostic quality evaluated as number of inconclusive examinations significantly improved, falling from 40.7% at baseline down to 5.1%. Furthermore, SonoVue significantly (p<0.01) increased the accuracy, sensitivity and specificity of assessment of disease compared with baseline ultrasound. SonoVue increases the diagnostic quality of Doppler images and improves the accuracy of both spectral and colour Doppler examinations of extracranial carotid or peripheral arterial disease.

Transcranial duplex imaging with a sulfurhexafluoride echocontrast agent: enhancement and diagnostic quality.

BACKGROUND AND PURPOSE: The authors investigate characteristics of ultrasound enhancement and diagnostic quality of a sulfurhexafluorides (SF6)-containing echocontrast agent (SonoVue) in cerebrovascular patients with insufficient temporal bone window by transcranial color-coded duplex (TCCD) sonography. METHODS: Thirty patients (mean age = 62.2 +/- 11.1 years) were enrolled. SF6 was administered intravenously in 4 different doses (0.3, 0.6, 1.2, and 2.4 mL). By videotape analysis, time to contrast appearance, duration of contrast enhancement, and duration of clinically useful signal enhancement were measured. Overall quality of ultrasound investigation was also assessed. RESULTS: Time to contrast appearance ranged from 11 to 74 seconds (mean = 26 seconds). For the 0.3, 0.6, 1.2, and 2.4 mL doses, average times to contrast appearance of 30 +/- 12 seconds, 28 +/- 10 seconds, 23 +/- 8 seconds, and 22 +/- 6 seconds were measured. Duration of TCCD signal enhancement was 438 +/- 169 seconds, 483 +/- 195 seconds, 713 +/- 299 seconds, and 788 +/- 344 seconds for the different doses. Clinically useful enhancement was 160 +/- 124 seconds, 200 +/- 157 seconds, 260 +/- 166 seconds, and 327 +/- 239 seconds. CONCLUSIONS: Administration of SonoVue led to a quality improvement in 21 patients. In TCCD, it optimizes visualization of the cerebral arteries in patients with inadequate bone window. A dose of at least 1.2 mL provides the best enhanced images.

Multi-centre clinical study evaluating the efficacy of SonoVue (BR1), a new ultrasound contrast agent in Doppler investigation of focal hepatic lesions.

OBJECTIVES: SonoVue is a new ultrasound contrast agent, which consists of stabilised microbubbles of a sulphur hexafluoride gas. The aim of the study was to assess its efficacy in the Doppler investigation of focal hepatic lesions. MATERIALS AND METHODS: Seventy patients with focal liver tumours were studied. Four doses (0.3, 0.6, 1.2 and 2.4 ml) of SonoVue were administered intravenously with at least 10 min delay between each injection. A complete colour/power and spectral Doppler imaging investigation of the lesions was performed at baseline pre-dosing and after each SonoVue injection. All examinations were recorded on SVHS videotapes. Baseline and post contrast videotapes were reviewed by the on-site (un-blinded) investigators and by two off-site blinded readers (a) to grade the global quality of the Doppler scans of the focal lesions vascularity and the normal parenchymal vessels (b) to measure the duration of clinically useful Doppler signal enhancement and (c) to determine the diagnostic accuracy and performance of the enhanced versus unenhanced scans using histopathology, tumour markers, CT and/or MR as the reference standard. RESULTS: A statistically significant improvement was observed at all four SonoVue doses in the off site assessment of global quality of the Doppler examination of tumoral and normal parenchymal vessels in comparison with the baseline (P < 0.05). The median duration of clinically useful enhancement was significantly increased with increasing doses (P < 0.001), ranging between 1.4-2.2 min for the lowest dose and 3.2-3.8 min for the highest dose for the off-site readers. On-site assessment of diagnostic accuracy showed a significant increase in the specificity of the Doppler diagnoses (P < 0.0016) with an increase in the positive and negative predictive values and in the likelihood ratio in differentiating between benign and malignant lesions. Off-site evaluation showed a significant increase in the accuracy of enhanced Doppler diagnosis in comparison with the baseline performance. CONCLUSION: The results suggest that SonoVue is effective in improving the display of tumoral vascularisation and may be useful in the characterisation of focal liver lesions.

Evaluation of the efficacy of two leishmanins in asymptomatic dogs.

There are few studies in dogs concerning leishmanin skin test. We evaluated and compared the efficacy of two leishmanin preparations for the detection of dog Leishmania cellular-mediated immunity. Clinically healthy dogs living in an endemic area were studied. A leishmanin preparation 1 (3 x 10(8) promastigotes/ml) was superior to a leishmanin preparation 2 (5 x 10(6) promastigotes/ml), measured as the percentage of positive reactions and the diameter of the induced induration. The leishmanin skin test is a valuable tool, although the results show that the degree of response, as it has been shown in human beings, depends on the preparation used.

SonoVue in transcranial Doppler investigations of the cerebral arteries.

BACKGROUND AND PURPOSE: The authors investigated the safety and diagnostic potential of a new ultrasound contrast agent (SonoVue) using transcranial color-coded duplex sonography (TCCS). METHODS: Forty patients were enrolled in a multicenter, open-label (on-site), blind (off-site), randomized, dose-ranging crossover study. SonoVue was administered as an intravenous bolus injection of 4 different dosages (0.3, 0.6, 1.2, and 2.4 mL). Efficacy was evaluated as (1) off-site assessment of global quality of the Doppler investigation (based on color or power Doppler images and spectral analysis) at baseline and following each dose of SonoVue according to a 4-point scale (from very poor to excellent imaging of blood flow) and (2) duration of clinically useful signal enhancement and color or power Doppler visualization of blood flow. Additional on-site efficacy assessments performed following each dose of SonoVue included confidence in diagnosis and global consequences of contrast enhancement on diagnosis. Safety evaluations included clinical laboratory tests, neurological examination, injection site tolerability, and incidence of adverse events and their relationship to the study agent. RESULTS: All doses of SonoVue significantly improved the global quality of Doppler examinations (P < .05). The median duration of clinically useful enhancement was dose related (P < .001) and ranged from 2 to 6 minutes at the highest dose. The administration of the contrast agent changed a nondiagnostic study to a diagnostic one in 66% of patients and increased the confidence in diagnosis in 74% of cases. No serious adverse events were recorded following SonoVue administration. The observed adverse reactions were all transient and mild in intensity. CONCLUSIONS: The results obtained from this multicenter study demonstrate that the administration of SonoVue to patients with ischemic cerebrovascular disease who undergo TCCS examination of cerebral vessels improves the visualization of intracranial arteries, providing a dose-dependent contrast enhancement and a clinically useful duration of signal enhancement related to the dose. During this multicenter study, SonoVue proved to be a safe and well-tolerated compound.

A new Doppler signal enhancing agent for flow assessment in breast lesions.

OBJECTIVE: To determine the diagnostic performance of SonoVue (Bracco) in the enhancement of Doppler signals in breast lesions and in the improvement of diagnostic accuracy. METHODS: This multicenter study included 220 patients undergoing investigations of parenchymal lesions, 40 of which had breast tumors. After a baseline Doppler examination, intravenous doses of 0.3, 0.6, 1.2 and 2.4 ml SonoVue were injected. Doppler signal quality before and after injection was compared. Off-site assessment of the global quality of Doppler signal and duration of clinical useful enhancement, as well as off-site and on-site evaluation of quality of color and spectral Doppler, were performed. On-site evaluation of diagnostic accuracy was also carried out. Safety assessments included monitoring of adverse events up to 24 h following the last injection of SonoVue. RESULTS: On-site evaluations: baseline Doppler was conclusive in only 4/21 carcinomas and in 2/17 benign lesions. Enhanced Doppler improved differential diagnosis in 20/21 carcinomas and in 9/12 benign lesions. Time to color enhancement was 0.55 min for the lowest and 0.35 min for the highest dose. The total duration of enhancement was 3.47 min for the lowest and 5.62 min for the highest dose, respectively. Off-site assessment: SonoVue improved the quality of Doppler blood flow information both in parenchymal and focal lesions. Statistically significant changes from baseline in global quality of Doppler investigations were observed at all four SonoVue doses (P<0.05). The duration of clinically useful signal enhancement increased with doses and a significant dose relationship was obtained (P<0.001). Mild adverse events were observed in two patients only. CONCLUSION: The results obtained from this study, following both off-site and on-site assessment, demonstrate that the administration of SonoVue to patients with focal breast lesions provides significant improvement over the baseline of Doppler signal quality and a clinically useful duration of signal enhancement, related to the dose. SonoVue was shown to be a safe and well-tolerated compound.

The Ibizian hound presents a predominantly cellular immune response against natural Leishmania infection.

Veterinarians working in the Balearic Islands (Mallorca), an endemic region of canine leishmaniosis, have reported very few cases of leishmaniosis in Ibizian hounds while concurrently observing that dogs of other breeds had a high incidence of clinical canine leishmaniosis. To further investigate this observation, two populations of dogs from the Balearic Islands were examined for the presence of Leishmania-specific cellular immunity using a delayed type hypersensitivity test (DTH) to leishmanin and for the presence of Leishmania-specific humoral immunity using an ELISA. Fifty-six asymptomatic dogs, 31 Ibizian hounds and 25 dogs belonging to other breeds were examined. Seventy-seven percent of the dogs demonstrated a specific immune response against Leishmania, either humoral or cellular. This finding suggests that the infection rate (77%) was higher than previously considered. For Ibizian hounds 81% were DTH positive while only 48% of the other dogs were DTH positive. A statistical association between Ibizian hounds and positive DTH response was found. A specific humoral response was found in 48% of Ibizian hounds and in 56% of the other dogs. No statistical association relative to the Leishmania-specific IgG1 and IgG2 levels were found between the two groups. The Ibizian hound has been reported to be more resistant to Leishmania infection and we found that the Ibizian hound mounts a significant cellular response to infection. Thus, the Ibizian hound may be an interesting canine model for the investigation of protective anti-Leishmania immune response.

Human pharmacokinetics and safety evaluation of SonoVue, a new contrast agent for ultrasound imaging.

RATIONALE AND OBJECTIVES: To assess in humans the pharmacokinetics of SonoVue, a new echo contrast agent based on stabilized sulfur hexafluoride (SF6) microbubbles and to provide additional safety and tolerability information on the compound. METHODS: The blood kinetics and pulmonary elimination of SF6 after intravenous bolus injection of two dosage levels (0.03 and 0.3 mL/kg) of SonoVue were evaluated in 12 healthy subjects (7 men, 5 women). In addition, safety and tolerability were evaluated by monitoring vital signs, adverse effects, discomfort, and physical examination and laboratory parameters associated with the SonoVue injection. RESULTS: The blood kinetics of SF6 was not dose dependent. SF6 was rapidly removed from the blood by the pulmonary route, with 40% to 50% of the injected dose eliminated within the first minute after administration and 80% to 90% eliminated by 11 minutes after administration; the elimination was similar in men and women and independent of dose. Both dosages were well tolerated. No adverse effects were observed immediately or during the 24-hour follow-up period. CONCLUSIONS: SonoVue was shown to be rapidly removed from the blood. The route of SF6 elimination was by means of the lungs in the expired air. SonoVue appeared to be safe and well tolerated in healthy subjects.

Cold exposure induces different uncoupling-protein thermogenin masking/unmasking processes in brown adipose tissue depending on mitochondrial subtypes.

The effect of cold exposure on thermogenic parameters such as mitochondrial protein content, GDP-binding and uncoupling protein (UCP) levels in different mitochondrial fractions from rat brown adipose tissue has been investigated. Rats were exposed from 12 h to 5 days at 4 degrees C, and three mitochondrial fractions were isolated by differential centrifugation: the M1 fraction (1000 g), the M3 fraction (3000 g) and the M15 fraction (15,000 g). Cytochrome c oxidase activity as an index of mitochondrial mass showed an increase during cold exposure. During the first 24 h of cold exposure UCP was incorporated specifically into the M3 and M15 mitochondrial fractions, and thereafter UCP appeared in the heaviest M1 fraction. However, specific GDP binding was increased during the first 24 h in the same way in all subpopulations, and this increase continued up to 72 h of cold exposure. Results suggest that different molecular events are involved during acute and chronic adaptation to cold: during the first 24 h of cold acclimatization, thermogenic activity is increased by an unmasking process of the UCP binding sites in the M1 mitochondrial fraction as UCP levels were constant and GDP binding increased, but in the M3 and M15 fraction the increase in thermogenic activity was completely due to an increase in GDP binding induced by a specific incorporation of UCP targeted to these mitochondria. Thus thermogenic parameters change in a different way in the brown-fat mitochondrial subpopulations during cold acclimatization.

Complement activation on the nasal mucosal surface--a feature of the immediate allergic reaction in the nose.

Complement is a system of functionally linked serum proteins that interact to exert biologic effects in inflammatory and immunologic processes. As part of a larger study with a potential topical antiallergic drug, we measured C3a des Arg and C5a des Arg in 13 patients with seasonal allergic rhinitis and in five nonatopic controls after placebo treatment. After 1 week of placebo treatment, a nasal allergen challenge with increasing doses of pollens was performed in both allergic subjects and controls. A symptom score method was used, and in returned nasal lavage fluid, the activity of C3a des Arg and C5a des Arg was measured. We found that allergen challenge in the allergic subjects induced nasal symptoms concomitantly with increased levels of C3a des Arg and C5a des Arg (P < 0.05). No increases either in symptoms or in the very low base-line levels of C3a des Arg and C5a des Arg were observed in the nonallergic controls. We conclude that the activation of the complement cascade is one part of the vasculature exudative response during the immediate allergic reaction in the upper airways. Because of their biologic potency, these proteins may be an essential part of the exudative response which perpetuates the ongoing inflammatory reaction.

[Dimethindene maleate administered via intramuscular route in man: local and systemic tolerance]. / Maléate de dimétindène, administré par voie intramusculaire chez l'homme: tolérance locale et systémique.

Local and systemic tolerance of dimethindene maleate was studied in 10 healthy volunteers by the intramuscular route (4 mg in 4 ml solvent). Subjective perception of pain and other reported side effects were registered and objective signs at the injection site were assessed repeatedly. Hematologic and biochemical tests were performed before and after completion of the study. Two volunteers complained about local pain immediately and one hour after the injection. An other volunteer developed a small hematoma within 48 hours after injection. No other side effects or adverse reactions were noted. Good tolerance of dimethindene maleate after intramuscular application could thus be established.

Pharmacokinetic study of 14C-letosteine in man after oral intake and steady-state.

Based on previous animal and on preliminary human results a further human study was performed in order to confirm the relevant pharmacokinetic parameters and the lack of accumulation of letosteine after repeated administrations. Thus, six healthy male volunteers were given a single oral dose of 50 mg (100 microCi) 14C-letosteine in form of gelatine capsules. A treatment lasting 11 days to obtain a steady-state was started three days later with three similar daily oral doses of unlabelled letosteine. Then, one capsule of 14C-letosteine was administered again. The radioactivity of blood, plasma, urine and expired air was measured at regular intervals after both radioactive doses. Several pharmacokinetic parameters were calculated for the single oral intake and for the oral intake at steady state. The results show a good absorption rate of letosteine since about 90% of the dose was found in the urine. Elimination was biphasic, with half-lives of about 1 and 4 hours in blood and plasma. No striking differences were recorded between the single oral intake and the oral intake at steady state for the various parameters assessed: Cmax, Tmax, AUC, Aeurine and AeCO2. It was therefore concluded that repeated doses of letosteine did not influence the absorption, the distribution, the metabolism and the elimination processes.

[Study by radiolabelling of the residual time of a therapeutic gel in the nasal fossae]. / Etude par radiomarquage de la rémanence d'un gel thérapeutique dans les fosses nasales.

The residence times in the nose of the liquid and gel forms of the same therapeutic preparation were compared in 7 healthy subjects. A 50 microliters drop of the preparation, labelled with Tc99m, was placed down the head of the inferior turbinate, and the kinetics of its clearance from the site of deposition was monotired using a gamma camera, during 60 minutes for the liquid and 120 minutes for the gel. The average times for removal of 50% of the labelled material from the site of deposition were 10.3 minutes and 28.6 minutes for the liquid and gel forms respectively. The slower removal of the gel form is probably due to a mechanical effect, and seems to affect the whole nasal passage. The contact time between the preparation and the mucosa is increased in this galenic form and this should improve the efficiency of the preparation.

Pharmacokinetics of dimetindene after intravenous and oral administration to healthy volunteers.

The pharmacokinetics of dimetindene (dimethindene maleate, Fenistil, CAS 3614-69-5) were studied after its intravenous and oral administration to 8 healthy male volunteers. Serum concentrations were measured for 48 h using an enzyme-linked immunosorbent assay. Pharmacokinetic parameters (AUC, t1/2, CLs, Vd and F) were calculated using the clearance approach.

Effect of one month of lactitol treatment on calcium metabolism in man.

The chronic use of lactitol as a food additive or laxative might adversely affect calcium homeostasis. Its effect on calcium metabolism has been examined in an open cross-over study in 12 volunteers given 20-40 g lactitol per day for one month. Compared to a control period without lactitol, the disaccharide did not alter the urinary excretion of calcium, inorganic phosphate or hydroxyproline, nor did it alter the circulating levels of calcium, phosphate, alkaline phosphatase, parathormone and osteocalcin. Chronic treatment with lactitol in laxative doses had no measurable effect on calcium metabolism in man.

Lactitol: gastrointestinal absorption and effect on blood lactate in healthy volunteers and patients with cirrhosis.

The gastrointestinal absorption of lactitol has been studied in 6 healthy volunteers and 8 patients with cirrhosis. Following administration of lactitol 0.5 g/kg, no lactitol was found in serum. The urinary excretion of lactitol over 24 h ranged from 0.1 to 1.4% of the administered dose (0.46% in cirrhotics and 0.35% in healthy volunteers). Blood D- and L-lactate and plasma glucose did not increase following lactitol. The data indicate that lactitol was poorly absorbed from the gastrointestinal tract in healthy volunteers and patients with cirrhosis, and that the disaccharide did not disturb glucose or lactate homeostasis.