Symbiotic properties of Methylobacterium nodulans ORS 2060T: A classic process for an atypical symbiont     

Adeline Renier  Philippe Jourand  Sylvie Rapior  Véréna Poinsot  Abdoulaye Sy  Bernard Dreyfus  Lionel Moulin 《Soil biology & biochemistry》2008,40(6):1404-1412

Some legume species of the Crotalaria genus are specifically nodulated by methylotrophic bacteria belonging to the Methylobacterium nodulans species. The feature of this symbiotic bacterium is its ability to oxidize methanol, a property based on the presence of a methanol dehydrogenase enzyme. Despite a good knowledge of this property and its implication in symbiosis, the molecular dialogue between M. nodulans and crotalaria podocarpa leading to symbiosis is largely unknown, except the presence of a nodA nodulation gene in the genome of M. nodulans ORS 2060. To investigate if M. nodulans ORS 2060 produces Nod factors, molecules considered as the major bacteria-to-plant signals essential for the establishment of rhizobia–legume symbiosis, we identified and sequenced a nodDABCUIJHQ cluster from a genomic library of ORS 2060. Phylogenetic analyses of nod genes revealed that M. nodulans ORS 2060 form a branch together with Burkholderia tuberum STM678 and a strain of Methylobacterium sp. (4-46) isolated from Lotononis, and distinct from all the other rhizobia. To analyse the regulation of ORS 2060 nod genes, we constructed a nodA–LacZ promoter fusion to monitor the nod gene expression with various flavonoids. The flavone apigenin was found to be the strongest inducer of nod gene expression in M. nodulans ORS 2060. This latter flavonoid was used to induce ORS 2060, and Nod factors were purified by high-performance liquid chromatography (HPLC) and further characterized by mass spectrometry. One major Nod factor structure was identified as a pentamer of chitin substituted by C18:1 or C16:0 acyl chains on the non-reducing end and 6-O-sulphated on the other end, suggesting a classic symbiotic dialogue between M. nodulans and C. podocarpa.  相似文献   

Larval instars determination for the European Grapevine Moth (Lepidoptera: Tortricidae) based on the frequency distribution of head-capsule widths     

Lionel Delbac  Patrice Lecharpentier  Denis Thiery 《Crop Protection》2010

Morphological measurements such as head-capsule (HC) width can be very useful and accessible tools that may be employed for classifying Lepidopteran larval instars according to stage of life history. The availability of such measures is crucial in the management of larval pests, because their control relies upon making accurate assessment of the life history stage at which larvae has reached in various environmental conditions. Such forecasts are then used in order to estimate the timing of emergence for future adult populations. Previous studies investigated the use of head-capsule widths from field larvae of European Grapevine Moth (EGVM), Lobesia botrana Den. and Schiff., to describe the distributions of the five instars during three generations of the insect. The observations were performed in 1998 and 2002 in a vineyard near Bordeaux. The results presented here increase the scope of earlier methods by providing statistical confidence. Our method was calibrated on a large number of individuals (N = 552) issued from our insect culture and uses a nonlinear least-squares parameter estimation to describe the distribution of each larval instar inside each generation. The model was tested on a wild larval population (n = 3007) occurring in our experimental vineyard during two complete years. The instar class ranges and boundaries were characterized with the associated probabilities of misclassification. A final classification statistical model is developed for each instar and each generation. From this study, we conclude that larval HC sizes increase statistically according to the generation of the year, and thus is influenced by grape phenology.  相似文献   

Phytoanticipins from banana (<Emphasis Type="Italic">Musa acuminata</Emphasis> cv. Grande Naine) plants,with antifungal activity against <Emphasis Type="Italic">Mycosphaerella fijiensis</Emphasis>, the causal agent of black Sigatoka     

Carlos A. Cruz-Cruz  Gerardo Ramírez-Tec  Karlina García-Sosa  Fabiola Escalante-Erosa  Lionel Hill  Anne E. Osbourn  Luis M. Peña-Rodríguez 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(4):459-463

The previously detected antifungal activity against Mycosphaerella fijiensis of aqueous infusions of healthy banana (Musa acuminata cv. Grande Naine) leaves, suggested the production of phytoprotectants by the plant. The bioassay-guided VLC-purification of the lyophilized infusion of the leaves of 4-month old healthy banana (M. acuminata cv. Grande Naine) plants, resulted in the purification of a phytoanticipin with strong antifungal activity against M. fijiensis Morelet, the causal agent of black Sigatoka, the most destructive and devastating disease of bananas and plantains in the world. The LC-MS analysis of the purified phytoanticipin suggests a steroidal saponin structure with four sugar units attached to the C-3 position of a diosgenin-like aglycone. This represents the first report of phytoanticipins occurring in M. acuminata.  相似文献   

Lymphocytic Thyroiditis in the Dog   总被引：1，自引：0，他引：1  

Lionel E.  Mawdesley-Thomas 《The Journal of small animal practice》1968,9(11):539-550

Abstract— —A 0.4 per cent incidence of lymphocytic thyroiditis was seen in 4,500 dogs examined. The haematological and biochemical investigations failed to reveal any results of diagnostic significance. The histological features were reminiscent of a human Hashimoto's disease. Whilst the condition was similar to that seen in man, several significant differences were noted. A genetically linked auto-immune aetiology was considered the most likely.
Résumé— —La morbidité de la thyroïdite lymphocytaire constatée au cours de l'examen de 4.500 chiens atteignait 0,4 pour cent. Les examens hématologiques et biochimiques n'ont donné aucun résultat d'intérêt diagnostique. Les caractéristiques histologiques constatées évoquaient la maladie de Hashimoto chez I'homme. L'état des chiens étudiés ressemblait en principe à la maladie rencontrée chez I'homme, mais plusieurs différences ont été nottés. Il y a lieu de croire à une auto-immunitéà corrélation génétique.
Zusammenfassung— —Bei 4500 untersuchten Hunden wurde lymphocytische Thyreoiditis mit einer Häufigkeit von 0,4% beobachtet. Die hämatologischen und biochemischen Untersuchungen lieferten keine Ergebnisse von diagnostischer Bedeutung. Die histologischen Besonderheiten erinner-ten an die Hashimotosche Krankheit des Menschen. Obwohl der Zustand dem beim Menschen auftretenden glich, wurden doch mehrere Unterschiede bemerkt. Eine genetisch bedingte autoimmune Ätiologie wurde für am wahrscheinlichsten gehalten.  相似文献   

Mycobacterium szulgai infection in a captive population of African clawed frogs (Xenopus tropicalis).     

Norin Chai  Lionel Deforges  Wladimir Sougakoff  Chantal Truffot-Pernot  Amaury De Luze  Barbara Demeneix  Marie Clément  Marie Claude Bomsel 《Journal of zoo and wildlife medicine》2006,37(1):55-58

A colony of captive Xenopus tropicalis became infected with Mycobacterium szulgai. Clinical signs, when observed, were lethargy, weight loss, and emaciation. Visceral granulomas were common findings at laparoscopy and necropsy. The diagnosis of mycobacteriosis was based on histologic appearance and Ziehl-Neelsen staining of tissues. The identification of M. szulgai organisms was based on comparison of the 16S rRNA gene sequence with several GenBank databases. There have been no reports of this mycobacterial species as the causative agent of naturally occurring disease in amphibians.  相似文献   

Transmission of bovine viral diarrhea virus to adult goats from persistently infected cattle.   总被引：1，自引：0，他引：1  

Charles C Broaddus  G Reed Holyoak  Lionel Dawson  D L Step  Rebecca A Funk  Sanjay Kapil 《Journal of veterinary diagnostic investigation》2007,19(5):545-548

The transmission of bovine viral diarrhea virus (BVDV) from persistently infected (PI) heifers to adult seronegative goats was examined in this study. Ten seronegative adult goats were exposed to 4 PI heifers. None of the goats developed any clinical signs but all goats seroconverted by 42 days after exposure to the PI cattle. Results indicate that goats are susceptible to BVDV infection when housed with PI cattle.  相似文献   

Ocular surface physiology and aqueous tear secretion in cats of diverse cephalic conformations     

Jelena Oksa-Minaļto  David J. Maggs  Jekaterina Akimova  Aija Ilgaža  Lionel Sebbag 《Veterinary ophthalmology》2023,26(Z1):109-118

Objective

To describe normative ocular surface and aqueous tear testing data for cats of various cephalic conformation.

Animals studied

Fifty-three healthy adult cats (11 British Shorthair, 11 Burmese, 10 Devon Rex, 10 Scottish Fold, and 11 Sphynx).

Procedures

Blink rate, corneal tactile sensation (CTS), and Schirmer tear test with or without topical anesthesia (STT-1, STT-2) and with nasolacrimal stimulation (NL-STT1, NL-STT2) were assessed. Palpebral fissure length (PFL) and skull morphology were measured, and cephalic index (CI) and craniofacial ratio (CFR) calculated.

Results

Mean ± SD test results were as follows: blink rate (5.0 ± 2.3 blinks/min), CTS (3.2 ± 0.7 cm), STT-1 (11.2 ± 4.3 mm/min), STT-2 (6.7 ± 3.6 mm/min), NL-STT1 (13.4 ± 5.7 mm/min), NL-STT2 (13.5 ± 5.2 mm/min), and PFL (2.0 ± 0.2 cm). Corneal sensitivity did not differ significantly among breeds (p = .152) but was negatively correlated with body weight (r = −.32, p = .019). STT-1 significantly differed among breeds (p < .001) and was lowest in Sphynx cats (8.7 ± 4.3 mm/min). A positive correlation was detected between STT-1 values at 30 and 60 s (r = .98; p < .001). The nasolacrimal reflex significantly increased STT in anesthetized and unanesthetized eyes (approximately +100% and +20%, respectively; p ≤ .002). STT-1 tended to be higher in intact versus neutered cats (p = .062). Age did not impact any test result (p ≥ .085).

Conclusions

Normative data described here serve as a baseline for future studies assessing ocular surface disease in multiple feline breeds. Unlike dogs, brachycephalic cats did not have lower CTS or STT-1 than non-brachycephalic cats.  相似文献   

Standard and modified glabellar flap for medial canthus reconstruction following mass removal in three dogs and two cats     

Havi Sarfaty  Raaya Ezra-Elia  Nili Kahane  Shai Sandalon  Yifat Segev  Lionel Sebbag 《Veterinary ophthalmology》2023,26(2):121-127

Purpose

To describe the surgical technique and clinical outcomes of the glabellar flap and its modification for the reconstruction of the medial canthus following resection of tumors in three dogs and two cats.

Methods

Three dogs (7-, 7-, and 12.5-year-old mixed breeds) and two cats (10- and 14-year-old Domestic shorthair) presented with a 7–13 mm tumor affecting the eyelid and/or conjunctiva in the medial canthal region. Following en bloc mass excision, an inverted V-shaped skin incision was made in the glabellar region (i.e., the area between the eyebrows in humans). The apex of the inverted V-shaped flap was rotated in three cases, whereas a horizontal sliding movement was performed in the other two cases to better cover the surgical wound. The surgical flap was then trimmed to fit the surgical wound and sutured in place in two layers (subcutaneous and cutaneous).

Results

Tumors were diagnosed as mast cell tumors (n = 3), amelanotic conjunctival melanoma (n = 1), and apocrine ductal adenoma (n = 1). No recurrence was noted in a follow-up time of 146 ± 84 days. Satisfactory cosmetic outcome with normal eyelids closure was achieved in all cases. Mild trichiasis was present in all patients and mild epiphora was noted in 2/5 patients, but there were no associated clinical signs such as discomfort or keratitis.

Conclusions

The glabellar flap was easy to perform and provided a good outcome in terms of cosmetic, eyelid function, and corneal health. Postoperative complications from trichiasis appear to be minimized by the presence of the third eyelid in this region.  相似文献   

An eye on the Shih Tzu dog: Ophthalmic examination findings and ocular surface diagnostics     

Lionel Sebbag  Ana Paula S. M. Silva  Álex P. B. Santos  Ana Cláudia S. Raposo  Arianne P. Oriá 《Veterinary ophthalmology》2023,26(Z1):59-71

Objective

To characterize the ocular surface parameters and determine the prevalence of ocular pathology in Shih Tzu dogs.

Animal Studied

Fifty Shih Tzu dogs (28 male, 22 female).

Procedures

Each dog underwent a complete ophthalmic examination (recording any pathology) and a series of diagnostics, allowing for a 10 min-interval between tests: intraocular pressure (IOP), blink rate, palpebral fissure length (PFL), corneal tactile sensation (CTS), Schirmer tear test and nasolacrimal reflex without (STT-1, NL-STT1) and with topical anesthesia (STT-2, NL-STT2), tear ferning, strip meniscometry test (SMT), tear film breakup time (TFBUT), and punctate fluorescein staining (PFS) of the cornea.

Results

Mean ± SD test values were as follows: IOP (17.9 ± 3.7 mmHg), blink rate (2.4 ± 1.4 blinks/min), PFL (23.8 ± 1.8 mm), CTS (1.8 ± 0.7 cm), STT-1 (22.0 ± 5.5 mm/min), NL-STT1 (24.2 ± 4.7 mm/min), STT-2 (16.9 ± 6.5 mm/min), NL-STT2 (18.5 ± 7.5 mm/min), SMT (7.5 ± 3.5 mm/5 s), TFBUT (5.3 ± 2.4 s), tear ferning (1.3 ± 0.7), and PFS (1.6 ± 0.6). PFL was significantly greater in male vs. female Shih Tzus (p< .001). Age was negatively correlated with TFBUT results (r = −0.31, p = .027). Lagophthalmos was observed in 82% eyes. Ocular surface pathology was common, including adnexal abnormalities (100% eyes with caruncular trichiasis and medial lower lid entropion) and corneal opacification (27% pigmentation, 20% fibrosis, 12% neovascularization).

Conclusions

Qualitative tear film deficiency (low TFBUT), along with several anatomical abnormalities that promote ocular irritation and reduce globe protection, together help explain the concerningly high prevalence of ocular surface disease in the Shih Tzu breed. Prophylactic measures (e.g., medial canthoplasty, topical lubrication) could be considered to improve ocular health in Shih Tzus.  相似文献   

Corneal hypoesthesia,aqueous tear deficiency,and neurotrophic keratopathy following micropulse transscleral cyclophotocoagulation in dogs     

Lionel Sebbag  Elizabeth E. Crabtree  John S. Sapienza  Kay Kim  Elena Rodriguez 《Veterinary ophthalmology》2020,23(1):171-180

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