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To provide useful information based on the macropathology, histopathology and immunohistochemical investigation in the spleens of dogs with Babesia rossi infection. Control spleens were collected from four healthy dogs euthanized for welfare reasons. Nine dogs that died naturally because of a mono-infection with Babesia rossi were selected for the diseased group. One haematoxylin-and-eosin-stained section of splenic tissue from each of the infected and control dogs was examined under the light microscope. Immunohistochemical markers were applied to characterize different immunocyte populations. The application of analytic software enabled semi-quantitative comparison of leucocyte subpopulations. Routine splenic histopathology revealed diffuse intermingling of white and red pulp from infected dogs with a clear loss of distinction between these zones. Immunohistochemistry revealed an increase in the proportion of tissue resident and bone marrow origin macrophages in the infected spleens. Apart from a few remnant lymphocytes within the peri-arteriolar lymphatic sheaths and follicles, the majority of the immunocytes redistributed to the red pulp, supporting the observation of white and red pulp intermingling. The majority of our findings are in agreement with histomorphological descriptions of the spleen in a variety of noncanid mammalian hosts with lethal malaria or babesiosis.

A 4-month-old female entire Saint Bernard, a 10-month-old female spayed Great Dane and a 5-year-old male neutered Miniature Schnauzer cross poodle were presented with the primary complaint of chronic lameness. Subjectively, all three dogs were disproportionate dwarfs. Epiphysial dysgenesis was identified on survey radiographs in all three cases, along with varying degrees of secondary osteoarthrosis. Low serum thyroxine, in conjunction with low-to-normal thyroid stimulating hormone concentration, and the presence of epiphysial dysgenesis, served to confirm congenital hypothyroidism. Following commencement of synthetic thyroid hormone supplementation, resolution of clinical signs was noted within a 1-month period. Improvement in radiographic abnormalities was also seen over a 6-month period.

Aim To evaluate the effectiveness of chest physiotherapy (CPT), which provides slow and long expiratory flow and assisted cough techniques, in infants receiving outpatient care for acute wheezing episodes. Methods Forty-eight infants with moderate acute wheezing episodes were randomised to receive either salbutamol MDI with CPT (n = 25) or without CPT (n = 23). The clinical score and SpO2 levels were recorded, before and after treatment, in a blinded design. The primary outcome was discharge after the first hour of treatment: clinical score ≤5/12 and SpO2 ≥ 93%. Secondary outcomes were the number of admissions to hospital after the second hour, use of oral corticosteroid bursts and admissions to hospital on day seven. Results There were no differences between children with and without CPT in discharge rate (92% vs. 87%), clinical score (median [IQR]: 2.8 [2.2–3.3] vs. 3.4 [2.8–4.1]) and SpO2= (96.4 [95.7–97.1] vs. 96.0 [94.9–96.5]) after the first hour of treatment or in the number of hospital admissions after the second hour. No differences were observed at days seven and 28 following treatment. Conclusion There was no evidence of clinical benefits from these specific CPT techniques for infants receiving outpatient care for acute wheezing episodes.

Envenomation of domestic animals by snakes occurs frequently in certain geographic areas. However, reports describing clinical signs, clin- icopathologic abnormalities, therapeutic approaches, and outcomes are sparse. This review summarizes various snake families, venom types asso- ciated with harmful snakes, and the significant hematologic, hemostatic, and biochemical abnormalities associated with envenomation. Hematolog- ic abnormalities include RBC membrane abnormalities, hemolysis, hemo- concentration, leukogram changes, and platelet abnormalities, specifically thrombocytopenia. Coagulopathies associated with snake envenomation are well described in human medicine, and many studies have demon- strated properties of venoms that lead to both procoagulation and antico- agulation. As expected, similar abnormalities have been described in domestic animals. Biochemical abnormalities are associated with the effects of venom on tissues such as liver, skeletal and cardiac muscle, vas- cular endothelium, and kidney as well as effects on protein components and cholesterol. This comprehensive review of clinicopathologic abnor- malities associated with envenomation and their relationships to charac- terized venom constituents should be useful both in the diagnosis and management of envenomation and should serve as a foundation for future research in this field.

The genetic basis for the Ara-C resistance of CCRF-CEM Ara-C/8C leukemia cells was investigated. DNA sequencing revealed that these cells expressed an equilibrative nucleoside transporter 1 (ENT1) with a single missense mutation resulting in glycine to arginine replacement (G24R). To test the importance of this residue, additional G24 mutants were created and examined for [3H]-uridine and [3H]-Ara-C uptake. Both a G24E and G24A mutant showed reduced ENT1-dependent activity. An EGFP-tagged G24R ENT1 displayed plasma membrane localization even though it was unable to bind [3H]-NBMPR, an ENT1-specific inhibitor. These results define G24 as critical amino acid for ENT1 nucleoside uptake and suggest that mutations in TM1 may provide a mechanism for Ara-C resistance in CCRF-CEM Ara-C/8C cells.

Background: Despite treatment, many dogs still die of complications related to canine parvoviral (CPV) enteritis. Effective prognostication would be beneficial in managing this disease. Hypothesis: We hypothesize that the occurrence of leukocytopenias at admission and at 24 and 48 hours after admission, and changes in absolute leukocyte counts over time, could be used to predict outcome. Animals: Sixty-two puppies with confirmed CPV. Methods: A prospective study was performed. CBC was performed daily until discharge or death (in which case a postmortem examination was performed). Results: Of the nonsurvivors (10/62; 16%), 9 died because of complications of the disease and 1 was euthanized because of a poor prognosis. There was a statistical significant difference in the occurrence of leukocytopenias between groups at 24 and 48 hours postadmission. The survivors showed a significant increase over time in certain leukocyte types (specifically lymphocytes) compared with values at admission. The positive predictive value for survivors was high. Nonsurvivors had marked thymic and lymphoid atrophy and marked bone marrow hypocellularity. Conclusion: An accurate prognosis could be obtained at 24 hours after admission by evaluating the change in total leukocyte, band neutrophil, lymphocyte, monocyte, and eosinophil counts.

SUMMARY Bacillus Calmette-Guerin (BCG) infection of the spleen is a potent modifier of splenic function. Prior to malaria infection, we infected two mouse strains of differing susceptibility to Plasmodium chabaudi AS (C57BL/6 and A/J) with this mycobacterium. We then evaluated aspects of spleen cell composition, architecture and cytokine expression, and correlated these with the outcome. BCG preinfection resulted in protection of the A/J mice but paradoxically resulted in mortality of the C57BL/6 mice. The latter developed higher parasitaemias that peaked earlier than the A/J mice rendered resistant by BCG. BCG infection induced remarkable changes to splenic histology examined by H&E staining, but there were no consistent differences between mouse strains. C57BL/6 mice had higher absolute numbers of all immune cell phenotypes than did A/J mice, and higher macrophage and dendritic cell proportions. BCG-induced resistance in A/J mice was associated with an increased CD4 + expression of IFN- γ whilst induced death in C57BL/6 mice was associated with excessive IFN- γ expression. A moderate TH1 response in the A/J model may have been responsible for the improved survival, and an excessive TH1 response in the C57BL/6 model may have contributed to their death.

Peroxisome proliferator-activated receptors (PPARs) are key transcription factors in the control of lipid homeostasis and cell differentiation, but little is known about their function in oligodendrocytes, the major lipid-synthesizing cells in the central nervous system (CNS). Using the B12 oligodendrocyte-like cell line and rat spinal cord-derived oligodendrocytes, we evaluated the importance of PPARgamma in the maturation process of these cells. B12 cells express all PPAR isoforms (alpha, beta/delta, and gamma), as assessed by RT-PCR, Western-blot, and transactivation assays. B12 cells respond specifically to PPARgamma agonists by arresting cell proliferation and extending cell processes, events that are blocked by the PPARgamma antagonist GW9662. In addition, alkyl-dihydroxyacetone phosphate synthase (ADAPS), a key peroxisomal enzyme involved in the synthesis of myelin-rich lipid plasmalogens, is increased in PPARgamma agonist-treated B12 cells. In contrast with B12 cells, both immature and mature isolated spinal cord oligodendrocytes presented a high and similar expression level of ADAPS, as assessed by immunocytochemistry. However, as in B12 cells, isolated spinal cord oligodendrocytes were also found to respond specifically to PPARgamma agonists with a four-fold increase in the number of mature cells. Our data suggest a relevant role for PPARgamma in oligodendrocyte lipid metabolism and differentiation.

Peroxisome proliferator activated receptors (PPARs) are nuclear receptors that control important genes involved in lipid metabolism. Their role in nerve cells is uncertain, although anomalous myelination of the corpus callosum has been described in the PPARbeta-null mouse, and abnormalities of this tissue have been documented in fetal alcohol syndrome in humans. We report here that ethanol treatment of B12 oligodendrocyte-like cells induces a concentration- and time-dependent decrease in the mRNA and protein levels of PPARbeta, with no effect on PPARalpha or PPARgamma. The effect on PPARbeta is seen as an increase in mRNA degradation, as assessed by run-off assays, due to a significant decrease in PPARbeta mRNA half-life, with no observed changes in intracellular localization. Our results suggest a possible link between PPARbeta function and ethanol-induced abnormal myelination in oligodendrocytes.

Thirty-four dogs suffering from severe babesiosis caused by Babesia canis rossi were included in this study to evaluate acid-base imbalances with the quantitative clinical approach proposed by Stewart. All but 3 dogs were severely anemic (hematocrit

A case of chronic idiopathic intestinal pseudo-obstruction in an English bulldog is described. The dog was presented with chronic weight loss and vomiting. An intestinal obstruction was suspected based on clinical and radiological findings. A diagnosis of chronic idiopathic intestinal pseudo-obstruction was made on the basis of full thickness intestinal biopsies. The dog was refractory to any antiemetic therapy. Necropsy revealed marked atrophy and fibrosis of the tunica muscularis, together with a mononuclear cell infiltrate extending from the duodenum to the colon. This case was presented with clinical findings consistent with visceral myopathy in humans--namely, atony and dilatation of the whole gut--but the histological findings resembled sclerosis limited to the gastrointestinal tract.

Previous studies have shown that palmitoyl-carnitine is an anti-proliferative agent and a protein kinase C inhibitor. Two new palmitoyl-carnitine analogs were synthesized by replacing the ester bond with a metabolically more stable ether bond. An LD50 value in the nm range was found in anti-proliferative assays using HL-60 cells and was dependent on the alkyl-chain length. The inhibitory action of these water-soluble compounds on protein kinase C in vitro was greatly increased with respect to palmitoyl-carnitine and was dependent on the length of the alkyl chain. Its effect was mediated by an increase in the enzyme’s requirement for phosphatidylserine. Inhibition of the in situ phosphorylation of a physiological platelet protein kinase C substrate and of phorbol ester-induced differentiation of HL-60 cells was also observed. Finally, to test for isoenzyme selectivity, several human recombinant protein kinase C isoforms were used. Only the Ca2+-dependent classic protein kinase Cs (α, βΙ, βΙΙ and γ) were inhibited by these compounds, yet the activities of casein kinase I, Ca2+/calmodulin-dependent kinase and cAMP-dependent protein kinase were unaffected. Thus, these novel inhibitors appear to be both protein kinase C and isozyme selective. They may be useful in assessing the individual roles of protein kinase C isoforms in cell proliferation and tumor development and may be rational candidates for anti-neoplasic drug design.

The regulation of CNS lipid metabolism by nuclear receptors and their relation to cell differentiation remains undetermined. Since myelinating oligodendrocytes are the major lipid-synthesizing cells in the CNS, we characterized the effect of PPAR activation in a CNS derived cell line that expresses oligodendrocyte markers and compared these effects with oligodendrocyte primary cultures (90–95% pure). The rat glioma derived B12 cell line express the three major PPAR isoforms (PPAR α, β and γ) and present a large number of peroxisomes, indicating an important lipid metabolism. Treatment with ciprofibrate, a general PPAR activator and clinical hypolipidemic, induces proliferation arrest, process extension and a moderate rise in the expression of acyl-CoA oxidase, a specific marker of peroxisomal proliferation. Cell growth arrest by ciprofibrate is enhanced 100-fold by low concentrations of retinoic acid (0.01 μm), suggesting the involvement of the PPAR-retinoid acid receptor heterodimers. Since ciprofibrate possibly acts by modifying the concentration of endogenous PPAR ligands, we traced its effects to PPARγ by using isoform specific ligands: Troglitazone and 15-deoxy-prostaglandin J2, both of which induce growth arrest and process extension in B12 cells. These effects were corroborated on rat spinal cord derived oligodendrocytes primary cultures, where a significant rise in the number of mature oligodendrocytes is observed in response to PPARγ activators. These results show that PPARγ, a master gene in the differentiation of adipose tissue could be involved in the lipid metabolism of maturing oligodendrocytes.