Extranodal γδ-T-cell lymphoma in a dog with leishmaniasis

Abstract: An 8-year-old intact male mongrel dog with alopecia and weight loss was referred to the Veterinary Faculty of Naples. The dog had pale mucous membranes, enlarged prescapular lymph nodes, and splenomegaly. Laboratory abnormalities included anemia, thrombocytopenia, and hyperglobulinemia. Bone marrow aspirate smears contained numerous Leishmania amastigotes and an immunofluorescent antibody titer was strongly positive (1:1280) for leishmaniasis. The dog was treated with a combination of meglumine antimoniate and allopurinol for 60 days and showed clinical improvement. Two months after the end of treatment the dog was again referred because of relapse of leishmaniasis and the presence of a firm subcutaneous mass on the medial right thigh. Based on cytologic examination of fine needle aspirates of the mass, a diagnosis of large-cell lymphoma was made. Flow cytometry of tumor cells revealed γδ-T-cell lymphoma with a CD5+, CD3+, TCRγδ+, CD4−, CD8−, CD45RA+ immunophenotype. Using nested PCR, amastigotes were not detected in the neoplastic tissue. An association between leishmaniasis and hematopoietic tumors has been described rarely. γδ-T cells may be involved in the host response to this parasite, and prolonged antigenic stimulation and chronic immunosuppression (typical of leishmaniasis) play a crucial role in the etiopathogenesis of T-cell lymphoma.     

Serovar-specific prevalence and risk factors for leptospirosis among dogs: 90 cases (1997-2002)

OBJECTIVE: To estimate serovar-specific prevalence of leptospirosis by use of veterinary teaching hospital and laboratory submission data; describe annual and seasonal patterns of leptospirosis; and identify risk factors for age, sex, and breed. DESIGN: Retrospective study. ANIMALS: 90 dogs with leptospirosis. PROCEDURES: Hospital records of dogs examined at Purdue University Veterinary Teaching Hospital with a diagnosis of leptospirosis and laboratory records of dogs from which sera were tested for antibodies against Leptospira spp at Purdue University Animal Disease Diagnostic Laboratory from 1997 through 2002 were reviewed. The likely infecting Leptospira serovar was identified. Seasonal and annual prevalences were calculated by use of hospital population at risk (hospital cases) or serologic testing submissions (diagnostic laboratory cases). Age-, sex-, and breed-specific risk factors for hospital cases were estimated by odds ratios. RESULTS: Of the 39 hospitalized dogs identified, 34 had been serologically tested, and 22 of those were infected with Leptospira kirschneri serovar grippotyphosa. Of the 51 diagnostic laboratory cases, 59% had a reciprocal titer > or = 800 against serovar grippotyphosa. Diagnostic laboratory cases were more common in summer, whereas hospital cases of leptospirosis were more common in fall. Male dogs were at significantly greater risk of leptospirosis than female dogs; and dogs 4 to 6.9 years old were at significantly greater risk than dogs < 1 year old. CONCLUSIONS AND CLINICAL RELEVANCE: L kirschneri serovar grippotyphosa infection was associated with most cases of leptospirosis in dogs. Use of an effective vaccine that includes this serovar is advisable for dogs at risk of leptospirosis.     

Occurrence, isolation and biological activity of phytotoxic metabolites produced in vitro by Sphaeropsis sapinea, pathogenic fungus of Pinus radiata

Sphaeropsis sapinea was repeatedly isolated in Sardinia from symptomatic samples of the upper part of declining pine (Pinus radiata) plants. Observed symptoms mainly consisted of foliage chlorosis, drying of needles and cankers on branches. The S. sapinea strains were shown to produce phytotoxic metabolites in culture filtrates. Three metabolites were isolated for the first time from this fungus and identified by their spectroscopic and optical properties as R-(−)-mellein, (3R,4R)-4-hydroxymellein and (3R,4S)-4-hydroxymellein. When assayed for phytotoxic and antifungal activities on host and non-host plants and on some phytopathogenic fungi, the R-(−)-mellein showed significant activity, while the other two 3,4-dihydroisocoumarins showed only a synergic activity in both tests.     

Pharmacokinetics and efficacy of intravenous and extradural tramadol in dogs

Tramadol is a synthetic opioid agonist used extensively in human and, to a lesser extent, veterinary medicine throughout the world. The clinical efficacy and pharmacokinetic profile of intravenous (IV) and extradural (ED) tramadol (2 mg/kg) and its o-desmethyl metabolite were studied in dogs undergoing tibial plateau levelling osteotomy (TPLO). Intra-operative cardiorespiratory variables were monitored and post-operative pain was assessed using the short form of the Glasgow Composite Pain Scale. A rapid (<5 min) and effective production of o-desmethyl tramadol was recorded. The pharmacokinetic profile was similar for tramadol and its metabolite irrespective of the route of administration. ED tramadol provided sufficient intra- and post-operative analgesia without significant clinical side-effects, but the post-operative analgesia was comparable to that following IV administration and the ED route could therefore not be considered a practical alternative to the IV route.     

Antibacterial efficacy of polypyrrole in textile applications

This paper describes application and evaluation of polypyrrole as an antibacterial polymer. Polypyrrole was produced embedding two doping agents: chloride and dicyclohexyl sulfosuccinate ions. Stability of the antibacterial efficacy of polypyrrole deposited on cotton fabrics was assessed before and after three different kinds of washing (namely, laundering with anionic and non-ionic detergents and dry-cleaning). Polypyrrole showed excellent antibacterial properties (100 % of bacterial reduction) against Escherichia coli for both doping agents. Treated fabrics were further characterised by scanning electron microscopy, energy dispersive X-ray analysis and infrared spectroscopy. The antibacterial efficacy diminished after launderings with anionic and non-ionic detergents because of two different mechanisms: the neutralisation of positive charges under alkali conditions (dedoping), and a partial removal of polypyrrole by abrasion and surfactant action. After dry-cleaning, polypyrrole embedding chloride and dicyclohexyl sulfosuccinate ions still showed excellent antibacterial efficacy. Moreover, scanning electron microscopy investigations were used to intuitively explain the bactericidal mechanism of polypyrrole on Escherichia coli bacteria.     

Ultrastructural Observations and DNA Degradation Analysis of Pepper Leaves Undergoing a Hypersensitive Reaction to Xanthomonas campestris pv. Vesicatoria

Ultrastructural details of the hypersensitive reaction induced by infiltration with avirulent race 2 Xanthomonas campestris pv. vesicatoria in pepper Early Calwonder-10R leaves (incompatible interaction) are reported. Affected cells displayed plasmalemma undulations and disruption, lysis of the chloroplast membrane, degeneration of other organelles, general cytoplasm disorganisation and, often, protoplast shrinkage. The nuclei contained large masses of electron-dense material, apparently formed by chromatin aggregation. In many cases a single chromatin-like layer was deposited on the inner side of the nuclear envelope leaving a finely granular matrix in the centre of the nucleus; the nucleolus usually disappeared. The nuclear envelope was sometimes ruptured and the internal matrix leaked into the cytoplasm. The content of many affected cells eventually coagulated and became very electron-dense. The walls often collapsed. All these alterations were especially visible in spongy mesophyll cells at sites where bacteria occurred in the intercellular spaces. Although some of the nuclear and cytoplasmic alterations recall certain aspects of apoptotic cell death, molecular determinations did not reveal any DNA degradation in hypersensitively reacting tissues. The first cell alterations in leaves infected with the virulent bacterial race 1 (compatible interaction) were observed only 27h after inoculation, when the cytoplasm of some cells showed limited internal disorganisation and plasmolysis at sites where bacterial colonies developed.     

Pharmacokinetics of IV Ketorolac in Horses Undergoing Orchiectomy

Ketorolac (KET) is a nonsteroidal anti-inflammatory drug for human use, with a potent analgesic activity, that is used in the relief of moderate-to-severe postoperative pain. The pharmacokinetics of KET tromethamine was evaluated after single IV injection at 0.5 mg/kg body weight, after intubation and 10 minutes before surgery, to six Arabian colts undergoing orchiectomy. Intraoperative cardiorespiratory variables were monitored. Blood samples were collected for 36 hours, and serum samples were analyzed by high performance liquid chromotography with ultraviolet-visible detection. During surgery, all monitored physiological parameters were stable. Intermittent positive pressure ventilation, and normocapnia were maintained throughout the procedure in all animals. No adverse effects were observed. The kinetics of KET was described by a two-compartment models, and also a noncompartmental analysis was performed. The distribution and elimination half-lives were t_1/2λ1$t_{1/2{\lambda }_1}$ 0.06 ± 0.02 and t_1/2λ2$t_{1/2{\lambda }_2}$ 0.59 ± 0.21 hours, respectively. Body clearance and mean residence time were 339.99 ± 120.19 mL/h/kg and 0.49 ± 0.22 hours, respectively. The volume of distribution at steady state and volume of distribution based on the terminal phase were 218.83 ± 134.26 mL/kg and 522.5 ± 529.3 mL/kg, respectively. The serum protein binding was 75.8 ± 2.9%. The results indicate that KET at 0.5 mg/kg IV was very rapidly eliminated and thus was likely not effective in the postoperative period. However, further studies including a control group and at higher doses are suggested to investigate the KET kinetics and the analgesic efficacy in horse and define the most appropriate dosage scheme.