Degradation of citrate promotes copper co-precipitation within aluminium-(hydr)oxides in calcareous soils

In this study, we provide experimental evidences that in calcareous soils microbial degradation/decomposition of citrate can promote Al-(hydr)oxide precipitation concurrently decreasing copper (Cu) solubility by a coprecipitation process. Citrate is an organic acid anion commonly released by roots to increase nutrient availability or to limit Al toxicity. However, under specific environmental conditions (i.e. high microbial activity of Al-citrate-degrading bacteria, alkaline pH), this organic acid may become ineffective in mobilizing Cu for the plant acquisition process. To demonstrate this, a calcareous soil and an artificial soil system have been treated with citrate solutions; then, changes in Al and Cu solubility and the formation of Cu-containing Al-(hydr)oxides were monitored. Both in experiments with the artificial soil and in those where the soil was inoculated with microbial strains, the formation of Cu-Al coprecipitates not only occurred but was also concurrent with the decrease of Cu and Al solubility. The role of bacteria in metal-citrate complex degradation has been assessed, and the 16S rDNA of bacteria related with these processes has been sequenced for genus identification. Bacteria belonging to Pseudomonas, Sphingomonas, Bradyrhizobium and Sphingopixis have been identified as possible candidates to degrade Al- and Cu-citrate complexes thus triggering the metal precipitation phenomena.     

Nucleated erythrocytes in blood smears of dogs undergoing chemotherapy

The frequency of normoblastemia in dogs receiving chemotherapy is unknown. To provide this information, we calculated the percentage and number of nucleated erythrocytes (nRBCs) in blood of dogs treated for lymphoma (n = 284), mast cell tumour (n = 40) or carcinoma (n = 46). Relative normoblastemia (>1 or >5%) and absolute normoblastemia (>0.1 or >0.4 × 10³ µL^?1) were found after administration of vincristine (49.3, 20.5, 42.5, 19.2%, respectively), carboplatin (37.0, 2.2, 34.8, 13.0%), cyclophosphamide (30.8, 7.7, 23.1, 7.7%), doxorubicin (25.0, 8.3, 21.7, 6.7%), vinblastine and prednisone (25.0; 5.0; 22.5; 7.5%). Absolute normoblastemia was very severe (>1.0 × 10³ nRBC µL^?1) after administration of vincristine (9.6%), doxorubicin (3.3%), vinblastine and prednisone (2.5%). Absolute normoblastemia negatively correlated with RBC counts (P < 0.001) and positively (P < 0.001) with reticulocyte and WBC counts, but correlation coefficients were low (?0.19, 0.37, 0.15). Vincristine, doxorubicin or vinblastine and prednisone may induce severe normoblastemia. This may increase WBC counts and mask neutropenia associated with chemotherapy.     

Immunological role of the endosymbionts of Dirofilaria immitis: the Wolbachia surface protein activates canine neutrophils with production of IL-8

Filarial nematodes, including Dirofilaria immitis and D. repens, harbour intracellular bacteria belonging to the genus Wolbachia. These bacteria have been implicated in the pathogenesis of filarial diseases, possibly through their endotoxins. Recent studies have shown that a major surface protein of Wolbachia (WSP) induces a specific IgG response in hosts infected by D. immitis. WSP from the Wolbachia of D. immitis was produced in recombinant form. The purified protein was used in stimulation assays on canine neutrophils. The assays performed using a modified Boyden chamber showed that WSP stimulates neutrophil chemokinesis. In addition, RT-PCR revealed increased production of chemokine IL-8 by cells incubated with this protein. Neutrophils have been shown to play a major role in the pathogenesis of river blindness, and to accumulate in the nodules of onchocerciasis patients. In dogs infected by D. immitis, neutrophils accumulate in kidneys and in the wall of pulmonary arteries. As shown by our studies, Wolbachia could contribute to these inflammatory phenomena through its surface protein WSP, independently from its endotoxin component.     

Non-specific immunity and ketone bodies. I: In vitro studies on chemotaxis and phagocytosis in ovine neutrophils

The in vitro effects of the ketone bodies beta-OH-butyrate (2.4 or 4.8 mmol/l) and acetoacetate (2.4 or 4.8 mmol/l) on the uptake of latex particles (1.09 microns) and chemotaxis were investigated in ovine neutrophils. Because the acetoacetate used was a lithium salt, the effect of 2.4 or 4.8 mmol/l lithium chloride was also tested. Neutrophils from eight non-lactating, non-pregnant ewes were studied. The uptake of latex particles, as measured by a spectrophotometric method, showed wide individual variation. The phagocytotic activity was unaffected by 2.4 mmol/l ketone bodies and LiCl, but it was significantly inhibited by 4.8 mmol/l beta-OH-butyrate and activated by 4.8 mmol/l LiCl. The latter result could be masking an inhibitory effect of acetoacetate. Chemotactic movements of neutrophils, as evaluated in a modified Boyden chamber using homologous zymosan-activated serum (ZAS) as a chemoattractant, were slightly but significantly reduced by a 2.4 mmolar concentration of the ketone bodies, administered singly or simultaneously, and by LiCl. We conclude therefore that the inhibitory effect of lithium-acetoacetate could be due to its lithium component. The 4.8 mmol/l dose of acetoacetate and beta-OH butyrate significantly decreased chemotaxis only when both compounds were added simultaneously. No effect of 4.8 mmol/l LiCl was observed. These results suggest that ketone bodies, in particular beta-OH butyrate, could directly influence particle uptake and chemotaxis in neutrophils. Although other factors could decrease the efficiency of the immune system in ketotic ruminants, the effects of the ketone bodies on neutrophils functions may explain the high frequency of infectious disease during 'ketotic syndrome'. The immunomodulatory effect of lithium needs to be evaluated further and it should be considered when testing lithium compounds.     

Serum alpha1-acid glycoprotein (AGP) concentration in non-symptomatic cats with feline coronavirus (FCoV) infection

Previous studies have demonstrated that the concentration of alpha1-acid glycoprotein (AGP) transiently increases in asymptomatic cats infected with feline coronavirus (FCoV). In order to establish whether these fluctuations depend on the FCoV status, the serum concentration of AGP and anti-FCoV antibody titres and/or faecal shedding of FCoVs in clinically healthy cats from catteries with different levels of prevalence of FCoV infection were monitored over time. Serum AGP concentrations fluctuated over time in clinically healthy cats from the cattery with the highest prevalence of feline infectious peritonitis (FIP) and significantly increased just before an outbreak of FIP. Further studies are required to clarify whether the observed increase of AGP concentration is a consequence of the increased viral burden or a protective response against mutated viral strains. Nevertheless, the results of the present study suggest that AGP might be useful in monitoring FCoV-host interactions in FCoV-endemic catteries.     

Changes in Serum and Urine SAA Concentrations and Qualitative and Quantitative Proteinuria in Abyssinian Cats with Familial Amyloidosis: A Five‐year Longitudinal Study (2009–2014)

Background

Diagnosis of familial amyloidosis (FA) in Abyssinian cats usually is made on postmortem examination.

Hypothesis/Objectives

Sequential analysis of serum SAA (sSAA), urinary SAA (uSAA), urinary protein:creatinine (UPC) ratio, or sodium‐dodecylsulfate agarose gel electrophoresis (SDS‐AGE) may facilitate early identification of cats with FA.

Animals

Twenty‐three Abyssinian cats belonging to cattery A or B (low and high prevalence of FA, respectively).

Methods

Prospective longitudinal study using 109 blood and 100 urine samples collected over 4‐year period every 4 months, if possible, or more frequently in case of illness. Cats that died during study were necropsied. Health status of live cats was checked 5 years after enrollment. Serum amyloid A (sSAA) and urinary SAA (uSAA) were measured using ELISA kit. The UPC ratio and SDS‐AGE also was performed.

Results

Familial amyloidosis was not identified in cattery A, whereas 7/14 cats from cattery B had FA. Serum amyloid A concentrations were not significantly different between cats in catteries A and B or between cats with or without FA, despite frequent peaks in cats from cattery B. Conversely, uSAA was significantly higher in cattery B, especially in the terminal phases of FA. Proteinuria occasionally was found in cats from both catteries, especially in those with FA. Urine protein electrophoresis identified mixed proteinuria only in cats with FA.

Conclusions and Clinical Importance

Serum amyloid A and UPC ratio are not helpful for early identification of Abyssinian cats with FA. Conversely, increases in uSAA with or without mixed proteinuria may be found before onset of clinical signs in cats with FA.     

Multivariate Survival Analysis of Histological Parameters and Clinical Presentation in Canine Cutaneous Mast Cell Tumours

The Patnaik histological grade is a good method for the prediction of long-term mast cell tumour behaviour but it is influenced by subjective inter-observer variations and intratumoral heterogeneity. The present study evaluated each of the histopathological parameters used to formulate Patnaik’s grade in terms of prognosis and tested whether they have a different prognostic sensitivity, thereby disclosing which could be considered more useful in the prediction of tumour recurrence and patient survival. Clinical presentation (single or multiple tumours) was also considered as possible prognostic factor. The results demonstrated that individual histological criteria together with multiple presentation may be of value in predicting the outcome of mast cell tumours. Among these, invasiveness (β1.85; standard error 1.15) and the number of mitotic figures (β3.01; standard error 1.18) showed high prognostic significance (Cox proportional hazard regression for censored data ; chi-squared = 15.52, degree of freedom = 6, p = 0.016) and could serve as reliable prognostic indicators avoiding more subjective parameters such as cellular differentiation, nuclear morphology and tumoural pattern. R. Preziosi Deceased