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In the field of bioethics, scientific articles have already been published, and have highlighted relatively pluralist reflections concerning the creation and use of organoids. This plurality, rather than simply reflecting the complexity of the subject, may also be a consequence of the multiple theoretical and practical frameworks applied. Moreover, the creation and use of organoids in biomedical research and healthcare is probably in its infancy. This phenomenon is likely to increase in amplitude. Bioethics may be able to provide it with an effective and pertinent moral meaning, provided that a veritable metabioethical reflection is developed in parallel, that is, a reflection on bioethics itself, to provide scientists and clinicians with the best possible assistance in their everyday practice.

Ear cleaning is a therapeutic component in the management of otitis externa in dogs. The objectives of this study were to evaluate the in vivo efficacy and safety of a new ear cleanser, Sonotix® against EpiOtic® Advanced for the management of canine otitis externa. Eighteen clients owned dogs with a diagnosis of erythemato-ceruminous or purulent otitis externa were prospectively included and randomized to two treatment group: EpiOtic® Advanced and Sonotix®. Cytology and video-otoscopic examination (erythema, amount of cerumen and thickness and surface of ear canal covered by cerumen) of all affected ears were done at D0, both before (T0) and 30 minutes (T0 + 30 min) after ear cleaning. Then an ear medication was applied (Aurizon®, Vetoquinol). Owners were instructed to clean affected ears daily and apply the ear medication 30 minutes later for 5 days (D1-D5). Dogs were seen again at D6 for cytology and video-otoscopic examination. At T0, no significant differences were found between both ear cleansers groups regarding macroscopic and microscopic scorings. At T0 + 30 min and D6 cytological and video-otoscopic scores were significantly decreased (Wilcoxon test; p ® was statistically superior to Epiotic® as evidenced by the median global scores of video-otoscopic examination at T0 + 30 min (Mann Whitney Test, p ® seems to be more effective in removing cerumen than EpiOtic® Advanced.

In this study, the blood concentrations of enrofloxacin administered transdermally to 3 different reptilian species, Python regius , Acrantophis dumerili , and Boa constrictor imperator , at 50mg/kg was determined. The formulation used was a transdermal commercial vehicle, Pentravan cream, a hydrophilic base emulsion that uses the liposomal technique to penetrate the skin. The enrofloxacin was incorporated at 5wt% in the Pentravan cream, and the plasma concentrations of enrofloxacin and its metabolite ciprofloxacin were measured using high-performance liquid chromatography. The results showed that the detected amounts of enrofloxacin and ciprofloxacin (0.33 and P. regius and B. constrictor , while ciprofloxacin was detected only in A. dumerili . Although the values were unquantifiable, this study confirms the absorption of enrofloxacin. Therefore, these findings suggests that enrofloxacin may be a candidate for treatment using the transdermal route in certain reptile species.

Canine atopic dermatitis (cAD) is a major teaching point as its diagnosis and treatment are difficult. During 11 weeks, 140 dogs and students (third, fourth, and fifth years) were recruited and paired. One of the four lists of diagnostic criteria was randomly attributed to each student. Concordance results, calculated with Cohen's kappa, ranged from slight (κ=0.07) to moderate (κ=0.53). Favrot's diagnostic criteria received the best results. It has been observed that results are improved with clinical experience. We observed that students often forgot that Favrot's criteria apply only to pruritic dogs and that the fulfillment of the criteria allows only a suspicion, not a diagnosis, of cAD. Primary pruritus and corticosteroid-responsive pruritus were often misunderstood.

A female checkered giant cross rabbit ( Oryctolagus cuniculus ) was presented with skin lesions on the perineal region. The cutaneous lesions extended 2cm from the vulva and perineal glands. They were moist and erythematous, with abundant greasy yellowish scabs. Skin scrapings from the lesions were mounted in Amman's chloral-lactophenol on microscope slides and examined at ×10 and ×40 magnification. Numerous mites were observed and identified as Psoroptes cuniculi , a common causal agent of otitis externa in rabbits. The rabbit was treated successfully with ivermectin. This case of psoroptic mange is atypical owing to the perineal location, apparent absence of auricular lesions, and the lack of contagion despite close contact with several other rabbits.

An 11-year-old, spayed female domestic shorthair cat was presented for a right flank wound. On clinical examination, a single non-painful skin tear lesion with irregular edges was detected. During the examination, star-shaped cigarette paper-like skin lesions appeared spontaneously. An abdominal mass was also palpated. Feline skin fragility syndrome (FSFS) was suspected and a multicentric lymphoma was diagnosed by fine needle aspiration. The cat’s condition declined and it died spontaneously. Post-mortem examination confirmed the diagnosis of lymphoma. Neoplastic lymphocytes were not observed in the skin. Histological analysis of the skin was consistent with the morphological aspects of FSFS. A possible direct link between the two conditions remains a matter of speculation, but this case report provides the first description of FSFS associated with multicentric follicular lymphoma. Thus, multicentric follicular lymphoma should be considered as a differential diagnosis in cats presenting with FSFS.

Assessment of ocular discomfort caused by veterinary care products is less legitimately regulated than that caused by human care products. The Slug Mucosal Irritation (SMI) assay was adapted to evaluate canine hygiene shampoos to predict ocular discomfort. Experiments were performed using four commercial canine shampoos, a baby care product, and two controls (ArtTear® and BAC1%). Groups of 3 slugs were tested with 5% dilution of the 7 test substances. The negative control (ArtTear®) was the best tolerated. The baby care product Mixa bebe as well as Douxo Entretien Demelant and Phlox Shampooing Entretien were classified to cause mild ocular discomfort. Together with the positive control (BAC 1%), Shampooing Physiologique Virbac and Physiovet Shampooing were considered to cause severe ocular discomfort. Different intensities of ocular discomfort were measured for veterinary care products. The SMI model was considered as a reproducible and adaptable evaluation method for screening veterinary care products causing ocular discomfort.

Hypersensitivity dermatitides (HD) are often suspected in cats. Cats with HD are reported to present with one or more of the following patterns: miliary dermatitis, eosinophilic dermatitis, self-induced symmetrical alopecia or head and/or neck excoriations. Previous reports on feline HD included small numbers of animals, took place in geographically restricted areas or did not compare these conditions with other causes of pruritus. The goal of the present study was to analyse 72 parameters covering signalment, clinical, laboratory and treatment characteristics from a large group of pruritic cats from different geographical areas. Of the 502 cats, the following diagnoses were made: flea HD (29% of cases), food HD (12%) nonflea/nonfood HD (20%) and other diseases in which pruritus was a feature (24%). Cats with signs consistent with a HD but which did not complete a food trial were not analysed further (15% of cases). Most cats with nonflea HD exhibited signs compatible with one or more of the four typical lesional patterns, but none of these patterns was found to be pathognomonic for any specific diagnosis. Food HD and nonflea/nonfood HD were found to be clinically undistinguishable. Young adult, purebred and female cats appeared predisposed to nonflea/nonfood HD. As many diagnoses presented with similar lesional patterns, a thorough clinical work-up is required for establishment of a specific diagnosis.

Animal reservoirs and primary hosts of Bartonella Bartonella are hemotropic bacteria that infect numerous wild and domestic mammals, and some are directly responsible for zoonotic infections. There are 27 currently known species or subspecies of Bartonella. Wild and domestic animals represent a large reservoir for Bartonellae, but man is the unique reservoir for two species. Reservoirs are characterized by a long-lasting bacteremia, sometimes with recurrences. Cats have long been considered as an asymptomatic reservoir of Bartonella, but direct and indirect (serological) evidence indicate that they too can be affected by Bartonella infection. Dogs are considered as accidental hosts for Bartonella, and clinical features in this species are very similar to those seen in man. The most frequent signs reported in dogs and man include endocarditis, ocular, neurologic, articular, renal, and even skin disorders, as well as systemic manifestations. Endocarditis has also been described in cattle. In reservoir species, the main vectors of Bartonella are hematophagous arthropods, such as cat flea (Ctenocephalides felis), ticks (genus Ixodes), or the louse-fly (Hippoboscidae). Blood culture, serology and PCR are used for the diagnosis of Bartonella infection in reservoir hosts. As no vaccines are available, prevention in carnivores relies mostly on appropriate tick and flea control. The outcome of the treatment of these infections remains uncertain and does not result in complete bacterial eradication., Les Bartonella sont des bactéries hémotropes infectant de nombreux mammifères domestiques ou sauvages, et plusieurs d’entre elles sont directement incriminées comme agents de zoonoses. On connaît actuellement 27 espèces ou sous-espèces de Bartonella. Les animaux domestiques et sauvages représentent un réservoir important des Bartonella, mais l’homme est l’unique réservoir pour deux d’entre elles. L’état de réservoir se caractérise par une bactériémie au long cours, éventuellement accompagnée de récurrence(s). Le chat a longtemps été considéré comme un hôte réservoir n’exprimant pas de symptômes, mais des preuves directes et indirectes (sérologiques) indiquent que cette espèce peut aussi être affectée par Bartonella. Le chien est plutôt considéré comme un hôte accidentel, avec un tableau clinique se rapprochant de celui de l’homme. Les symptômes les plus courants chez ces deux espèces sont ceux d’endocardites, d’atteintes oculaires, neurologiques, articulaires ou rénales, voire cutanées, associées à des manifestations générales. Des endocardites sont aussi décrites chez les bovins. Au sein des réservoirs, la transmission se fait principalement par l’intermédiaire d’arthropodes hématophages, comme la puce du chat (Ctenocephalides felis), les tiques (du genre Ixodes) ou les mouches piqueuses (Hippoboscidae). Le diagnostic de ces infections chez les animaux réservoirs s’appuie sur l’hémoculture, la sérologie et la recherche de l’ADN (par PCR) à partir de différents prélèvements. Puisqu’il n’existe pas de vaccins, la prévention de l’infection chez les carnivores consiste essentiellement à lutter contre les acariens grâce à des traitements adaptés. Le traitement de ces infections chez les animaux reste aléatoire et ne permet pas une éradication définitive de la bactérie., Boulouis Henri-Jean, Marignac Geneviève, Haddad Nadia, Maillard Renaud, Chomel Bruno. Les animaux réservoirs et victimes des Bartonella. In: Bulletin de l'Académie Vétérinaire de France tome 161 n°3, 2008. pp. 211-220.

Resume Les Bartonella sont des bacteries hemotropes infectant de nombreux mammiferes dont l'homme. Les animaux domestiques et sauvages constituent un important reservoir de bartonelles et au moins 25 especes sont actuellement decrites dont plusieurs sont directement incriminees comme agents de zoonoses. La transmission des bacteries au sein des reservoirs est assuree par des arthropodes hematophages. La transmission s'effectue par voie directe (griffades, morsures,...) du reservoir animal a l'homme. Trois maladies principales sont decrites chez l'homme : maladie de Carrion (B. bacilliformis), fievre des tranchees (B. quintana) et maladie des griffes du chat (B. henselae). Un certain nombre de pathologies isolees est associe a des infections par d'autres especes de Bartonella, mais celles-ci sont moins frequentes. Les endocardites constituent les atteintes les plus graves. Le diagnostic de ces infections recourt a la serologie, l'histologie, l'hemoculture et la recherche de l'ADN bacterien a partir de differents prelevements. L'antibiotherapie, necessaire dans les cas graves, utilise des informations obtenues par quelques etudes d'antibiosensibilite. La prevention de l'infection consiste essentiellement a lutter contre les acariens grâce a des traitements adaptes, puisqu'il n'existe pas de vaccin.

Summary Objective of the study Shampoo therapy is often recommended for the control of Malassezia overgrowth in dogs. The aim of this study was to evaluate the in vivo activity of a 2% climbazole shampoo against Malassezia pachydermatis yeasts in naturally infected dogs. Animals Eleven research colony Beagles were used. Materials and methods The dogs were distributed randomly into two groups: group A (n = 6) and group B (n = 5). Group A dogs were washed with a 2% climbazole shampoo, while group B dogs were treated with a physiological shampoo base. The shampoos were applied once weekly for two weeks. The population size of Malassezia yeasts on skin was determined by fungal culture through modified Dixon's medium contact plates pressed on left concave pinna, axillae, groins, perianal area before and after shampoo application. Samples collected were compared by Wilcoxon rank sum test. Results Samples collected after 2% climbazole shampoo application showed a significant and rapid reduction of Malassezia population sizes. One hour after the first climbazole shampoo application, Malassezia reduction was already statistically significant and 15 days after the second climbazole shampoo, Malassezia population sizes were still significantly decreased. No significant reduction of Malassezia population sizes was observed in group B dogs. Conclusion The application of a 2% climbazole shampoo significantly reduced Malassezia population sizes on the skin of naturally infected dogs. Application of 2% climbazole shampoo may be useful for the control of Malassezia overgrowth and it may be also proposed as prevention when recurrences are frequent.

Onset of atopic dermatitis and occurrence of related skin lesions are influenced by various environmental factors in humans, and companion animals. Several studies have demonstrated an association between passive smoking and the development of atopic dermatitis in children. This association has never been investigated in the dog to our knowledge. We enrolled 161 dogs seen at dermatology and vaccination consultations over a six-month period for this study. Dog owners were asked to complete a questionnaire, to evaluate the exposure of the dog to tobacco smoke. The atopic or non-atopic status of the dog was assessed on the basis of Favrot's criteria (history, clinical examination and cutaneous cytology for Malassezia). Analysis of the data for the 161 dogs enrolled revealed a significant association between high levels of passive exposure to tobacco smoke (cigarette consumption divided by the area of the home) and the presence of atopic dermatitis in the dogs (OR, 4.38; 95% CI, 1.10-17.44; p=0.03; NNH (number needed to harm) 3, 95% CI 2-52). The prevalence of atopic dermatitis showed a slight, but non-significant association with breed predisposition. Dogs with high levels of exposure to tobacco smoke may have a higher risk of atopic dermatitis than non-exposed dogs.

Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD.

This study investigated the efficacy and safety of masitinib, a selective tyrosine kinase inhibitor capable of downregulating mast cell functions, for treatment of canine atopic dermatitis (CAD). Dogs with confirmed CAD received masitinib at 12.5 mg/kg/day (n = 202) or control (n = 104) for 12 weeks. A reduction in CAD Extent and Severity Index (CADESI-02) score of ≥ 50% at week 12 was observed in 61% of masitinib-treated dogs versus 35% of control dogs (P0.001), according to the modified intent-to-treat population. For dogs resistant to ciclosporin and/or corticosteroids (60% of the study population), CADESI-02 response rates were 60 versus 31%, respectively (P = 0.004). The mean reduction in pruritus score of severely pruritic dogs was 46 versus 29%, respectively (P = 0.045). Furthermore, 65% of owners with severely pruritic dogs assessed masitinib efficacy as good/excellent versus 35% control (P = 0.05). Overall, 63% of investigators assessed masitinib efficacy as good/excellent versus 35% control (P0.001). Premature discontinuations from the modified intent-to-treat population (28.2% masitinib versus 26.0% control) were mainly due to adverse events (13.4 versus 4.8%, respectively) or lack of efficacy (12.4 versus 18.3%, respectively). In total, 13.2% dogs presented with severe adverse events (16.0% masitinib versus 7.7% control). Masitinib showed a risk of reversible protein loss, although regular surveillance of blood albumin and proteinuria allowed for discontinuation of treatment while the dog was still clinically asymptomatic. Masitinib proved to be an effective and mostly well-tolerated treatment of CAD, including severe and refractory cases, with medically manageable adverse effects.

Hypersensitivity dermatitides (HD) are often suspected in cats. Cats with HD are reported to present with one or more of the following patterns: miliary dermatitis, eosinophilic dermatitis, self-induced symmetrical alopecia or head and/or neck excoriations. Previous reports on feline HD included small numbers of animals, took place in geographically restricted areas or did not compare these conditions with other causes of pruritus. The goal of the present study was to analyse 72 parameters covering signalment, clinical, laboratory and treatment characteristics from a large group of pruritic cats from different geographical areas. Of the 502 cats, the following diagnoses were made: flea HD (29% of cases), food HD (12%) nonflea/nonfood HD (20%) and other diseases in which pruritus was a feature (24%). Cats with signs consistent with a HD but which did not complete a food trial were not analysed further (15% of cases). Most cats with nonflea HD exhibited signs compatible with one or more of the four typical lesional patterns, but none of these patterns was found to be pathognomonic for any specific diagnosis. Food HD and nonflea/nonfood HD were found to be clinically undistinguishable. Young adult, purebred and female cats appeared predisposed to nonflea/nonfood HD. As many diagnoses presented with similar lesional patterns, a thorough clinical work-up is required for establishment of a specific diagnosis.

Bacterial pathogens typically infect only a limited range of hosts; however, the genetic mechanisms governing host-specificity are poorly understood. The α-proteobacterial genus Bartonella comprises 21 species that cause host-specific intraerythrocytic bacteremia as hallmark of infection in their respective mammalian reservoirs, including the human-specific pathogens Bartonella quintana and Bartonella bacilliformis that cause trench fever and Oroya fever, respectively. Here, we have identified bacterial factors that mediate host-specific erythrocyte colonization in the mammalian reservoirs. Using mouse-specific Bartonella birtlesii, human-specific Bartonella quintana, cat-specific Bartonella henselae and rat-specific Bartonella tribocorum, we established in vitro adhesion and invasion assays with isolated erythrocytes that fully reproduce the host-specificity of erythrocyte infection as observed in vivo. By signature-tagged mutagenesis of B. birtlesii and mutant selection in a mouse infection model we identified mutants impaired in establishing intraerythrocytic bacteremia. Among 45 abacteremic mutants, five failed to adhere to and invade mouse erythrocytes in vitro. The corresponding genes encode components of the type IV secretion system (T4SS) Trw, demonstrating that this virulence factor laterally acquired by the Bartonella lineage is directly involved in adherence to erythrocytes. Strikingly, ectopic expression of Trw of rat-specific B. tribocorum in cat-specific B. henselae or human-specific B. quintana expanded their host range for erythrocyte infection to rat, demonstrating that Trw mediates host-specific erythrocyte infection. A molecular evolutionary analysis of the trw locus further indicated that the variable, surface-located TrwL and TrwJ might represent the T4SS components that determine host-specificity of erythrocyte parasitism. In conclusion, we show that the laterally acquired Trw T4SS diversified in the Bartonella lineage to facilitate host-restricted adhesion to erythrocytes in a wide range of mammals., Author Summary Pathogens are—as the result of adaptive evolution in their principal host(s)—typically limited in the range of hosts that they can infect successfully. However, infrequently such host-restricted pathogens may undergo a spontaneous host switch, which can lead to the evolution of pathogens with altered host specificity. Most human pathogens evolved this way, and animal-specific pathogens have thus to be considered as an important reservoir for the emergence of novel human pathogens. Despite host-specificity representing a common feature of pathogens, the underlying molecular mechanisms are largely unknown. In this study we have used bacterial pathogens of the genus Bartonella to identify bacterial factors involved in the determination of host specificity. The bartonellae represent an excellent model to study host-specificity as each species is adapted to cause an intracellular infection of erythrocytes exclusively in its respective reservoir host(s). Using a genetic approach in combination with erythrocyte infection models in vitro and in vivo we demonstrate that a surface-located bacterial nanomachine—a so-called type IV secretion system—determines host specificity of erythrocyte infection. Our work sheds light on the molecular basis of host specificity and establishes an experimental model for studying the evolutionary processes facilitating spontaneous host shifts.

As a model of persistent infection, various aspects of Bartonella birtlesii infection in laboratory mice, including some immunodeficient mice, are presented, particularly focusing on conditions mimicking natural infection. Bacteraemia was explored using different mice strains routes and inoculum doses (3.4–5 × 107 CFU/mouse). Mice became bacteraemic for 5 (C57Bl6/6) to 10 weeks (Balb/c, Swiss) with peaks ranging from 2 × 103 to 105 CFU/mL of blood. The ID route induced the most precocious bacteraemia (day 3) while the higher and longer bacteraemia in immunocompetent mice was obtained with SC when infecting Balb/c with approximately 103 CFU/mouse. As opposed to ID, SC and IV routes, bacteraemia was obtained with the oral and ocular routes only for high doses (107) and in 33–66% mice. It was significantly higher and longer in CD4−/− mice compared to CD8−/− and double KO mice at most time points. CD8−/− mice and the control group had near to superimposed kinetics. These results confirm the relevance of the present model.

The objective of this study was to develop a standard operating procedure for the analysis of skin wound healing using histomorphometrical measurements and mathematical data analyses. The mathematical model is derived from observations of normal cutaneous healing in the rabbit. It is designed to allow a simple scoring of the major steps of healing and remodelling. Full-thickness punch biopsies were performed on the skin of the back of New Zealand-white rabbits and healing was analyzed by histopathological examination after 2, 5, 9 and 14 days, using different staining techniques. Histomorphological measurements were also made. The thickness of the epidermis and neo-epidermis were compared. Several indices relative to wound severity and contraction were computed in an attempt to defi ne a global healing index. A remodelling index was calculated based on a colorimetric analysis with Mallory Trichrome staining and hair migration. The changes in indeks values seemed to correlate with the histopathological analysis. No material flaws appeared when this model was applied to the natural healing process. This model was developed for scoring and accurate comparative evaluation of the effects of various treatments, biomaterials or pharmacological preparations on soft tissue healing and remodelling in rabbits. Although the healing of cutaneous wounds in rabbits differs from that in humans, this model may still be relevant for screening new wound healing preparations., Cilj ovog istraživanja je razvijanje osnovne metode za analizu zaraštavanja kože služeći se histomorfometrijskim mjerenjima i matematičkom analizom podataka. Matematički je model nastao promatranjem fi ziološkoga zarastanja kože u kunića. Model je razvijen za jednostavno mjerenje osnovnih faza zarastanja i remodeliranja rane. Potpuna biopsija kože provedena je na leđnoj koži novozelandskih bijelih kunića te je analiza zarastanja promatrana histopatološki nakon drugoga, petoga, devetoga i četrnaestoga dana rabeći različite metode bojenja. Također su izvršena histomorfološka mjerenja. Uspoređene su vrijednosti debljine fi ziološkoga i novonastaloga epidermisa. Nekoliko indeksa povezanih sa zarastanjem i kontrakcijom kože pribrajani su s pokušajem utvrđivanja potpunoga indeksa zaraštavanja. Kolometrijska analiza s Mallory trichrome bojenjem korištena je za izračun remodelirajućega indeksa i promatranja migracije dlačnoga folikula. Promjene u vrijednosti indeksa mogu se povezati s histopatološkom analizom. Prirodni proces zarastanja promatran je bez utjecaja čimbenika koji mogu doprinijeti ishodu samoga zarastanja. Taj je model razvijen kako bi se moglo promatrati i uspoređivati različita liječenja, biomaterijali i farmakološki pripravci za zarastanje i remodeliranje mekoga tkiva u kunića. Unatoč razlici u zarastanju kože kunića i čovjeka, ovaj model može biti koristan za promatranje novih pripravaka za zaraštavanje rana.

Dissemination of Leishmania : a parasite sampled and picked up by the sandfly in the dermis of its vertebrate host. Study of an experimental model : Leishmania major and C57Bl/6 mouse. Parasites establish with their host a series of dynamic interactions, clinically visible or asymptomatic, on which depends their durability. Leishmania major is a protozoan parasite dependent on two hosts : (a) a hemophage and telmophage insect, the sandfly, and (b) a rodent. Following the inoculation, when and where do the Leishmania in their amastigote form migrate from the initial site ? In our laboratory, an infection model was developed based on current knowledge on hemophagia in telmophage sandflies. We prepared 1000 metacyclic promastigote Leishmania and inoculated them to C57Bl/6 mice via intradermal injections in the centre of the right pinna. This study, based on real-time/ quantitative PCR (qPCR) to quantify kinetoplastic DNA (kDNA), has shown that Leishmania were established in the centre of the inoculated pinna. On day 4 after the injection, we detected Leishmania kDNA in the periphery of that pinna and in the draining lymph node. The parasitic load grew regularly until day 28, then decreased between days 28 and 49. The maximum value recorded in the centre of the ear was 10,000 parasites on day 28, less in the periphery. The skin of the tail was the distant skin site where the detection of kinetoplastic kDNA was most consistent, starting on day 4. These results confirm the data on the kinetics of the parasitic load at the injection site. They also support the presence, within days after the inoculation, of a few parasites in asymptomatic distant cutaneous sites. The technique of qPCR to detect asymptomatic carriage has several applications both in Veterinary Medicine and in Public Health. The potential implications of these results on the parasite cycle are also emphasized., Qu’elles soient visibles cliniquement ou asymptomatiques, la pérennité des parasites est sous-tendue par les interactions dynamiques qu''ils établissent avec leurs hôtes. Leishmania major est un parasite protozoaire dépendant de deux autres organismes hôtes : (a) un insecte hématophage et telmophage, le phlébotome, (b) un rongeur. À partir de quand et où des leishmanies au stade amastigotes peuventelles émigrer du site initial où elles ont été inoculées ? Dans notre laboratoire, un modèle d’infection a été développé en tenant compte de ce qui est connu sur l''hématophagie par telmophagie des phlébotomes. 1000 leishmanies au stade promastigote métacyclique sont préparées et inoculées en face interne du pavillon auriculaire de souris C57Bl/ 6, par voie intradermique. Ce travail, fondé sur la quantification par PCR en temps réel (PCRq) de l’ADN kinétoplastique (ADNk), a permis de montrer que les leishmanies s’établissaient au centre de l’oreille (site de l’inoculation). Au quatrième jour après l''injection, nous avons détecté l’ADNk des leishmanies à la périphérie de cette même oreille et dans le ganglion drainant. La charge parasitaire dans le centre augmente régulièrement, jusqu’au jour 28, puis diminue entre les jours 28 et 49. Pour le centre de l’oreille, la valeur maximale a été ≈ 10 000 parasites au jour 28, elle est moindre pour le bord. La peau de la queue a été le site cutané distant où il a été possible le plus régulièrement de détecter de l’ADN kinétoplastique et ce, dès le quatrième jour. Outre la confirmation des données sur la cinétique de la charge parasitaire au site d’injection, nos résultats sont en faveur de l’existence, dans les jours qui suivent l’inoculation, de quelques parasites dans des sites cutanés asymptomatiques. Les applications de la PCRq dans le cadre du concept de portage asymptomatique concernent aussi bien la Médecine Vétérinaire que la Santé Publique. Les implications potentielles par rapport au cycle parasitaire sont soulignées., Marignac Geneviève, Lebastard Maï, Fall Ndeye Gamou, Nicolas Luc, Milon Geneviève. Exploration de la dissémination de Leishmania, un parasite délivré et prélevé par le phlébotome au niveau du derme de l'hôte Vertébré. In: Bulletin de l'Académie Vétérinaire de France tome 156 n°2, 2003. pp. 41-45.

Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD.

Parasites establish dynamic relationships with their hosts that allow their persistence. Leishmania spp. are unicellular parasites that have two hosts: a haematophageous insect, the sand fly, and a vertebrate. Both in animals and humans, absence of clinical lesions does not imply absence of infection. This phenomenon has major implications in epidemiology, preventive medicine, and pharmacology. Parasitic load determination in mammalian tissues or organs is currently performed by culture-based methods that are time consuming and require samples harbouring cultivable parasites. Recently, we developed a real-time PCR assay to quantify the parasitic burden of several Leishmania spp. based on detection of kinetoplastic DNA (kDNA). The efficacy of this real-time PCR assay was first evaluated in monitoring the fate of Leishmania major in C57Bl/6 mice following intradermal inoculation of the right ear pinna with low doses of infective metacyclics at 24 h, 96 h, and weekly for 7 weeks. Leishmania were established in the center of the inoculated pinna, to a lesser extent in the pinna border, and in the draining lymph node. The parasite was detected, but not quantified, in distant cutaneous sites (left ear pinna, thorax skin, tail base) and in the femoral bone marrow. Throughout the whole experiment, the parasite was detected in the glabrous tail base skin. We also investigated whether the parasites detected by our method were still viable or if we were also detecting DNA from dead parasites. Technical and biological constraints have been overcome by developing an in vitro model to monitor the persistence of Leishmania kDNA in cultured mouse macrophages after host leucocytes were exposed to L-leucine-methyl ester, a leishmanicidal molecule. The detection of kDNA by real-time PCR was correlated with the viability of the parasites in macrophages. These results show that laboratory mice (experimental host) or in vitro-grown mouse macrophages infected with Leishmania parasites can be considered useful systems in two areas. First, in pharmacology, preventive medicine and epidemiology, such a system would allow pharmacological evaluation of Leishmania-targeted drugs or vaccines to a broader extent than merely monitoring the reduction of the lesion or the prevention of lesion onset. A similar system could be developed in other animal species, particularly the dog, in order to detect asymptomatic carriage at the borders or in quarantines, or to investigate the real prevalence of Leishmania spp. The growing importance of Leishmania infantum-related disorders in humans makes such a method very interesting. A second use for this experimental system is the investigation of the prompt and renewed interactions that Leishmania parasites establish within their mammalian hosts. Establishment of a system to quantify the parasitic burden of Leishmania spp. is the perspective of this preliminary research. Recently published data show that the apparent lack of symptoms hides complex mechanisms involving very different factors such as keratinocytes, epidermal and dermal leucocytes, the extracellular matrix, and sand fly saliva. Funding: Institut Pasteur, Centre National de la Recherche Scientifique.

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