Removal of sialoliths using the intraoral approach in 15 horses.

This study describes the use of an intraoral approach for sialolith removal in horses. All horses resumed their previous activity after surgery. Sialoliths were composed mainly of calcium carbonate, containing a nidus of plant material. The removal of sialoliths via an intraoral approach results in a high success rate with minimal complications.

Enlèvement des sialolithes en utilisant une approche intraorale chez 15 chevaux. Cette étude décrit l'utilisation d'une approche intra-orale pour l'enlèvement des sialolithes chez les chevaux. Tous les chevaux ont repris leurs activités antérieures après la chirurgie. Les sialolithes étaient principalement composés de carbonate de calcium contenant un nidus de matériau végétal. L'enlèvement des sialolithes par une approche intra-orale se traduit par un taux de succès élevé avec un minimum de complications.(Traduit par Isabelle Vallières).

Elemental Content of Calcium Oxalate Stones from a Canine Model of Urinary Stone Disease.

One of the most common types of urinary stones formed in humans and some other mammals is composed of calcium oxalate in ordered hydrated crystals. Many studies have reported a range of metals other than calcium in human stones, but few have looked at stones from animal models such as the dog. Therefore, we determined the elemental profile of canine calcium oxalate urinary stones and compared it to reported values from human stones. The content of 19 elements spanning 7-orders of magnitude was quantified in calcium oxalate stones from 53 dogs. The elemental profile of the canine stones was highly overlapping with human stones, indicating similar inorganic composition. Correlation and cluster analysis was then performed on the elemental profile from canine stones to evaluate associations between the elements and test for potential subgrouping based on elemental content. No correlations were observed with the most abundant metal calcium. However, magnesium and sulfur content correlated with the mineral hydration form, while phosphorous and zinc content correlated with the neuter status of the dog. Inter-elemental correlation analysis indicated strong associations between barium, phosphorous, and zinc content. Additionally, cluster analysis revealed subgroups within the stones that were also based primarily on barium, phosphorous, and zinc. These data support the use of the dog as a model to study the effects of trace metal homeostasis in urinary stone disease.

Mineral composition of urinary calculi from potbellied pigs with urolithiasis: 50 cases (1982-2012).

OBJECTIVE: To determine the mineral composition and anatomic location of urinary calculi and to investigate sex and reproductive status as predisposing factors for development of urolithiasis in potbellied pigs. DESIGN: Retrospective case series SAMPLES: Urinary calculi from 50 purebred and crossbred potbellied pigs. PROCEDURES: Laboratory records for urinary calculi of potbellied pigs submitted to the University of California-Davis Stone Laboratory from 1982 through 2012 were reviewed. Mineral composition of calculi was determined by polarized light microscopy, infrared spectroscopy, and, in some cases, x-ray diffractometry. RESULTS: Of the 48 urinary calculi analyzed by infrared spectroscopy, 21 (44%) were composed primarily of amorphous magnesium calcium phosphate; another 9 (19%) were primarily composed of calcium phosphate in the form of apatite. Of 50 urinary calculi, 22 (44%), 14 (28%), 10 (20%), 3 (6%), and 1 (2%) were removed from the urinary bladder only, urethra, both urinary bladder and urethra, urine, and renal pelvis, respectively. Sex of 6 potbellied pigs was not recorded. For 44 urinary calculi, 41 (93%) were from males (11 sexually intact males and 30 castrated) and 3 (7%) were from females (2 sexually intact females and 1 spayed). Among males, 73% (30/41) of submissions were from castrated males. CONCLUSIONS AND CLINICAL RELEVANCE: In contrast to results from studies in commercial pigs, the most common composition of urinary calculi identified in purebred and crossbred potbellied pigs was amorphous magnesium calcium phosphate. Potential predisposing factors for urolithiasis in potbellied pigs may be similar to those for urolithiasis in commercial pigs. These include diet, urinary tract infections, and sex. Thus, prevention of urolithiasis should target these potential predisposing factors.

Calcinosis cutis in dogs: histopathological and clinical analysis of 46 cases.

BACKGROUND: Calcinosis cutis is well recognized in dogs with endogenous hyperglucocorticism and iatrogenic hyperglucocorticism, but the pathogenesis is still unclear. OBJECTIVES: The objectives of the study were to identify possible correlations between histopathological patterns of dermal mineralization in skin biopsies and underlying causes for calcinosis cutis in dogs, as well as to determine breed predilection and age of onset for dogs within a hospital population. In addition, mineral analysis was performed on four biopsy samples. ANIMALS: Forty-six dogs with histopathologically confirmed calcinosis cutis were evaluated. METHODS: Medical records and histological sections of dogs with calcinosis cutis diagnosed by histopathology over a 21 year period were reviewed. Infrared spectrometry was used to identify the mineral in the paraffin blocks. Exact chi-squared test was used to identify breed predispositions, while a Mann-Whitney U-test was used to identify age correlations. RESULTS: Labrador retrievers, Rottweilers, boxers and Staffordshire terriers were the breeds most commonly affected in this study. Most dogs had either an exogenous or an endogenous source of corticosteroids, with the exception of five dogs with renal insufficiency. In the majority of cases, mineralization was found throughout the entire dermis. The average age of onset of calcinosis cutis for dogs with endogenous hyperglucocorticism was older than that of dogs with iatrogenic hyperglucocorticism. Using infrared spectrometry, apatite crystals were found to be the source of mineral. CONCLUSIONS AND CLINICAL IMPORTANCE: There was no observable difference in the histopathological pattern of calcinosis cutis from dogs with endogenous hyperglucocorticism versus iatrogenic hyperglucocorticism. While glucocorticoid therapy appears to predispose dogs to developing calcinosis cutis, it remains unclear whether there is a specific dose or combination of factors that initiates the mineral deposition. Furthermore, the mineral deposition in dogs with calcinosis cutis was found to be apatite.

Evaluation of culture techniques and bacterial cultures from uroliths.

The association between urolithiasis and growth of bacteria in the urine or urolith has not been recently evaluated in the past 15 years, and the effects of antimicrobial administration on urolith cultures have not been reported. As well, laboratory techniques for urolith cultures have not been critically evaluated. The objectives of the current study were to 1) report bacterial isolates from uroliths and their association with signalment, urolith composition, antimicrobial use, and urine cultures and 2) evaluate laboratory techniques for urolith cultures. For the first objective, a retrospective search of bacterial isolates cultured from uroliths submitted to the laboratory as well as the signalment, urine culture results, and antimicrobial use were recorded. For the second objective, 50 urolith pairs were cultured by washing each urolith either 1or 4 times and culturing the core. Five hundred twenty canine and 168 feline uroliths were reviewed. Struvite-containing uroliths had an increased prevalence of a positive culture compared to nonstruvite-containing uroliths (P < 0.0001, odds ratio [OR] = 5.4), as did uroliths from female dogs (P < 0.0001, OR = 2.9). No significant difference between culture results and previous antimicrobial administration was found (P = 0.41). Eighteen percent of cases with negative urine cultures had positive urolith cultures. There was no significant difference in core culture results whether the urolith was washed 1 or 4 times (P = 0.07). Urolith culture outcome was not always influenced by previous antimicrobial administration, and bacterial culture of a urolith may not yield the same results as those obtained from the urine. The modified protocol, which requires less time and expense for urolith cultures, may be an acceptable alternative.

Lidar characterization of crystalline silica generation and transport from a sand and gravel plant.

Light detection and ranging (Lidar) remote sensing two-dimensional vertical and horizontal scans collected downwind of a sand and gravel plant were used to evaluate the generation and transport of geologic fugitive dust emitted by quarry operations. The lidar data give unsurpassed spatial resolution of the emitted dust, but lack quantitative particulate matter (PM) mass concentration data. Estimates of the airborne PM10 and crystalline silica concentrations were determined using linear relationships between point monitor PM10 and quartz content data with the lidar backscatter signal collected from the point monitor location. Lidar vertical profiles at different distances downwind from the plant were used to quantify the PM10 and quartz horizontal fluxes at 2-m vertical resolution as well as off-site emission factors. Emission factors on the order of 65-110 kg of PM10 (10-30 kg quartz) per daily truck activity or 2-4 kg/t product shipped (0.5-1 kg quartz/t) were quantified for this facility. The lidar results identify numerous elevated plumes at heights >30 m and maximum plume heights of 100 m that cannot be practically sampled by conventional point sampler arrays. The PM10 and quartz mass flux was greatest at 10-25 m height and decreased with distance from the main operation. Measures of facility activity were useful for explaining differences in mass flux and emission rates between days. The study results highlight the capabilities of lidar remote sensing for determining the spatial distribution of fugitive dust emitted by area sources with intermittent and spatially diverse dust generation rates.

Airborne respirable silica near a sand and gravel facility in central California: XRD and elemental analysis to distinguish source and background quartz.

Despite the potential toxicity of respirable quartz to humans, little is known about the transport of airborne quartz from sources to receptors and how to distinguish anthropogenically generated quartz from natural background in a receptor sample. Airborne quartz emissions near a sand and gravel facility were determined using PM10 and PM2.5 filter samples collected at four downwind sites (D1: 22 m, D2: 62 m, D3: 259 m, and D4: 745 m from the facility) as well as one upwind site (U1: 1495 m) during summer sampling. X-ray diffraction was used to determine quartz concentration and elemental composition was analyzed using PIXE, XRF, PESA, and HIPS techniques. Elemental composition of the PM samples was used to determine the X-ray mass absorption coefficients that are essential for accurate quartz quantification by XRD. Elemental composition was found to be a useful tool to distinguish source and background crystalline silica. Both PM10 and PM2.5 samples collected at the D1, D2, and D3 sites contained more Si, Al, and Fe and less H, Na, and S, compared to those at the U1 site, whereas site D4 sample compositions were similar to those at the U1 site. A composite variable, SOIL/(H+Na+S), where SOIL = 2.20Al + 2.49Si + 1.63Ca + 1.94Ti + 2.42Fe, was used to distinguish source materials from background. Average dry season quartz concentrations in replicate PM10 samples were 4.6 +/- 0.9) microg m(-3) at U1, 60.6 (+/- 5.4) microg m(3) at D1, 62.4 (+/- 3.6) at D2, 32.6 (+/- 2.1) microg m(-3) at D3, and 9.41 (+/- 0.9) microg m(-3) at D4. The mass fraction of quartz was the highest at the D1 site and decreased with increasing distance from the facility. The mass of PM2.5 samples was too low to determine quartz concentrations. These results identify the facility as the main source of quartz and other silicate minerals downwind of the plant and that the air quality of the most remote sampling site, located approximately 750 m downwind, was still impacted by the facility's activity.