Modulation of human lymphocyte proliferation by salivary gland extracts of ixodid ticks (Acari: Ixodidae): effect of feeding stage and sex

Ixodid ticks remain attached to their hosts for several days to weeks. During this extended feeding process new proteins involved in the modulation of host immune responses are expressed in tick salivary glands. In our study a stimulatory or inhibitory effect of salivary gland extracts (SGE) of unfed and partially fed female Ixodes ricinus (Linnaeus, 1758), female and male Amblyomma variegatum (Fabricius, 1794) and Rhipicephalus appendiculatus Neumann, 1901 ticks on human lymphocyte proliferation induced by Concanavalin A (ConA) and phytohaemagglutinin (PHA), respectively, was investigated. SGE of all female ticks examined suppressed proliferation of ConA-induced lymphocytes; highly significant suppression was observed in the presence of unfed I. ricinus and 9-day fed A. variegatum SGE. SGE of partially fed A. variegatum and I. ricinus females suppressed PHA responses of lymphocytes. Lymphocytes showed reduced PHA and ConA responses in the presence of SGE of unfed and 2-day fed R. appendiculatus females, while SGE of 6-day fed females enhanced PHA responses, but reduced their ConA responses; generally SGE of 2-day fed females displayed the strongest inhibition. Amblyomma variegatum male SGE slightly enhanced PHA, but significantly reduced ConA responses of lymphocytes and their inhibitory effect increased during feeding. SGE of unfed and 2-day fed R. appendiculatus males enhanced PHA and ConA responses and those of 6-day fed males suppressed lymphocyte proliferation. The results suggest that (i) species- and sex-specific differences exist in the effects of tick salivary gland antigens on human lymphocyte proliferation and (ii) effect of SGE on human lymphocyte responses to mitogens varies depending on the tick feeding status.     

Ultraviolet spectrophotometric determination of the purity of technical pyrazon

A method for the analysis of technical samples of the herbicide pyrazon is described. A double-beam recording spectrophotometer with digital data recording accessory was used in the analysis of the multicomponent mixtures. The absorbances were measured in the u.v. region between 346 and 282 nm. Two alternative u.v. spectrophotometric methods are presented which allow the determination of all three components in technical products of pyrazon without any preliminary separation.     

Invasive and quarantine pests in forests in Slovakia1

Biological invasions of insects, plants, and fungal pest species often cause substantial disturbance to forest ecosystems and as well as severe socioeconomic impacts. Central Europe acts as a ‘bridge’ between Western and Eastern Europe both ecologically and as an important transit corridor for people. Human activity, including the movement of material goods, increases the risk of invasions. Some species introduced in the past have been established, becoming common and causing serious problems (such as Dreyfusia nordmannianae or Hyphantria cunea). The status, importance and spatial distribution in Slovakia of seven different forest pests recently introduced into Slovak forest ecosystems (Cameraria ohridella, Coleotechnites piceaella, Cryphonectria parasitica, Dothistroma septospora, Ips duplicatus, Parectopa robiniella, Phyllonorycter robiniellus) as well as two others not yet recorded in Slovakia (Anoplophora glabripennis, Phytophthora spp.) is discussed.     

Persistenz und Wirksamkeit von Bacillus thuringiensis — Präparaten in Freilandversuchen

The field persistence and efficacy of Bacillus thuringiensis formulations The persistence of spores ofBacillus thuringiensis (commercial formulation Dipel and Bathurin) on oak leaves under different climatic condition in field trials was determined. The killing activity of these preparations against wintermothOperophthera brumata and green oak tortrix Tortrix viridana was parallely tested. Within the first week after the application of bacterial preparations the viable spore count on leaves was reduced of two up to three orders. The efficacy of bacterial preparations depends, however, on the environmental temperature occurring within the first week after the application. The adequate temperature is the primary deciding for the feeding activity of caterpillars and for the virulence of the preparations. For aerial application doses of 0.5 to 1.0 kg of the preparation in 50 100 l of water per one ha were sufficient. In the contrary, Dipel WP in oil suspension was unsufficient for aerial application because of mechanical blocking of the nozzles. The optimal time for the procedure was the first week of May in our climatic conditions.      

Use of capecitabine to prevent acute renal allograft rejection in dog erythrocyte antigen-mismatched mongrel dogs

OBJECTIVE: To assess efficacy and toxicity of a capecitabine (CAP)-based regimen for preventing rejection of renal allografts in dog erythrocyte antigen (DEA)-mismatched mongrel dogs. STUDY DESIGN: Prospective, pilot study. ANIMALS: Eight healthy, unrelated, DEA mismatched, adult mongrel dogs. METHODS: All dogs received CAP, starting at 50 mg/m2 PO b.i.d. 4 days preoperatively, increasing to 200 mg/m2 PO b.i.d. by the day of surgery. All dogs received cyclosporine-A (CsA) and prednisolone starting 2 days preoperatively. Standard heterotopic renal transplantation with native nephrectomy was performed. After 90 days, surviving dogs were euthanatized and histopathologic examination was performed. RESULTS: Two of 8 dogs developed acute neurotoxicity leading to death or euthanasia within 5 days of surgery. For the 6 remaining dogs, there were no statistically significant changes in complete blood count or serum biochemical values. No opportunistic infections developed during the study period. Five of 6 dogs had no to minimal evidence of graft rejection. Two of 6 dogs developed superficial and pigmentary keratitis. Significant histopathologic findings in all dogs included mild lymphoplasmacytic gastroenteritis, steroid hepatopathy, and corneal epithelial thinning. One dog had moderate interstitial nephritis and pyelitis. CONCLUSIONS: In this experimental model, a CAP-CsA-prednisolone immunosuppressive regimen was effective in preventing rejection of allografts in DEA-mismatched dogs. Severe, unpredictable neurotoxicity and variable ocular toxicity significantly limit clinical applications at this time. CLINICAL RELEVANCE: A CAP-CsA-prednisolone protocol is an effective, oral immunosuppressive regimen for prevention of allograft rejection in DEA-mismatched mongrel dogs. For clinical application, identification of patients susceptible to toxic side effects would be necessary.     

Clinical application of recombinant human bone morphogenetic protein-2 in 4 dogs

OBJECTIVE: To describe outcome in dogs with insufficient bone healing treated with recombinant human bone morphogenetic protein-2 (rhBMP-2). STUDY DESIGN: Retrospective study. ANIMALS: Four dogs clinically affected with delayed union or nonunion bone healing. METHODS: Medical records were reviewed for signalment, clinical problem, treatment, and outcome. RESULTS: Four dogs that had delayed- or nonunion of bone fracture, osteotomy, or arthrodesis were treated with either minimally invasive, fluoroscopically guided, percutaneous administration or direct surgical application of rhBMP-2. Doses used ranged from 0.2 to 1.6 mg of rhBMP-2. In 3 dogs, a calcium phosphate matrix (CPM) carrier was used whereas in 1 dog commercially prepared rhBMP-2 impregnated in an absorbable collagen sponge (INFUSE Bone Graft) was used. This latter dog had osteomyelitis associated with implant infection before rhBMP-2 administration. Rapid radiographic union was noted in all dogs with excellent long-term outcome. Adverse effects were minimal and included transient worsening of lameness after percutaneous administration of rhBMP-2 in 2 dogs. CONCLUSIONS: rhBMP-2 stimulated rapid bone formation at delayed- or nonunion sites resulting in radiographic bone union with minimal adverse effects and excellent long-term outcome in 4 dogs. CLINICAL RELEVANCE: Direct intraoperative administration or fluoroscopically guided, minimally invasive delivery of rhBMP-2 may be an effective treatment modality for bone delayed- or nonunions and could potentially be used to stimulate new bone production in a variety of orthopedic surgical conditions in dogs.     

Density profile and morphology of viscoelastic thermal compressed wood

The viscoelastic thermal compression (VTC) of low-density hybrid poplar (Populus deltoides × Populus trichocarpa) from fast growing trees was performed in order to produce specimens with three different degrees of densification (63, 98, and 132%). The morphology and density profile of the VTC specimens were studied. Three different methods for the preparation of specimens for microscopy were used in order to find a technique that makes it possible to examine the VTC wood microscopically in the completely deformed state. It was found that the abrasive surface preparation of oil-embedded blocks was the most promising technique. Microscopic observation revealed that the deformations in the VTC wood were mostly the result of the viscous buckling of cell walls without fracture. The volume of the void areas in the specimens decreased with the degree of densification. The results showed that the density profile of the VTC wood varied with the degree of densification as a consequence of different temperature and moisture gradients formed before and during wood compression. The density profile is also visible on the cross-section of the VTC specimens.     

Antioxidant activity of Catalpa bignonioides

Antioxidant activity of methanolic extracts from inflorescence rachises, corollas, calyxes, leaves, valves of capsules and hypertrophied placenta of Catalpa bignonioides by 1,1-diphenyl-2-picrylhydrazyl reduction (DPPH) and tyrosine nitration inhibition induced by peroxynitrite was tested.