Xenogeneic equine stem cells activate anti-tumor adaptive immunity in a 4T1-based intraductal mouse model for triple-negative breast cancer: proof-of-principle.

Triple-negative breast cancer (TNBC) remains difficult to treat, especially due to ineffective immune responses. Current treatments mainly aim at a cytotoxic effect, whereas (stem) cell therapies are being investigated for their immune stimulatory capacities to initiate the anti-tumor immunity. Here, a thoroughly characterized, homogenous and non-tumorigenic mixture of equine mesenchymal stem cells (eMSCs) harvested from horse peripheral blood as innovative xenogeneic immunomodulators were tested in a 4T1-based intraductal mouse model for TNBC. The eMSCs significantly reduced 4T1 progression upon systemic injection, with induction of inflammatory mediators and T-cell influx in primary tumors, already after a single dose. These xenogeneic anti-cancer effects were not restricted to MSCs as systemic treatment with alternative equine epithelial stem cells (eEpSCs) mimicked the reported disease reduction. Mechanistically, effective eMSC treatment did not rely on the spleen as systemic entrapment site, whereas CD4+ and CD8α+ T-cell infiltration and activation were critical. These results show that eMSCs and potentially also other equine stem cell types can be a valuable TNBC treatment strategy for further (pre)clinical evaluation.

Regional cerebral blood flow in dogs with congenital extrahepatic portosystemic shunts before surgery and six months after successful closure.

Previous studies both in humans and dogs with chronic liver diseases have shown that regional cerebral brain flow (rCBF) is altered. The current study aimed to assess abnormalities in rCBF in dogs with congenital extrahepatic portosystemic shunts (cEHPSS), both at diagnosis and after successful surgical attenuation. Furthermore, the influence of age at diagnosis, severity of hepatic encephalopathy (HE) and type of cEHPSS on rCBF were explored as a base for future research. Single photon emission computed tomography (SPECT) with 99mtechnetium-hexamethylpropylene amine oxime tracer was performed before surgical attenuation and six months postoperatively. Twenty-four dogs with cEHPSS had SPECT at time of diagnosis and 13 dogs with a confirmed closed cEHPSS had a second SPECT six months postoperatively. At diagnosis, dogs with cEHPSS had an altered rCBF distribution compared to healthy dogs. This altered rCBF distribution seemed to be most apparent in dogs ≥ one year and in dogs with overt HE at diagnosis. Six months postoperatively, only the rCBF distribution in the subcortical region decreased compared to pre-operatively. In conclusion, all dogs with cEHPSS had altered rCBF which did not seem to normalize completely six months after successful surgical attenuation. Dogs diagnosed at an older age seemed to have more distinct abnormalities in rCBF compared to younger dogs.

Repeated specific canine pancreatic lipase measurements do not identify multiple acquired portosystemic shunts in dogs after extrahepatic portosystemic shunt attenuation.

BACKGROUND: In dogs with portal hypertension (PH), spec cPL is suggested to be increased despite normal pancreatic histology. After attenuation of congenital extrahepatic portosystemic shunts (cEHPSS), multiple acquired portosystemic shunt (MAPSS) can develop as consequence of sustained PH. Presence of MAPSS affects future therapeutic options and prognosis. OBJECTIVE: Evaluate if spec cPL concentrations increase postoperatively in dogs that develop MAPSS and can thus serve as an indicator of PH. ANIMALS: Twenty-four dogs with cEHPSS. METHODS: Dogs classified according to surgical outcome after cEHPSS attenuation (8 with MAPSS [group M], 9 with closed cEHPSS [group C] and 7 with patent blood flow through the original cEHPSS, without evidence of MAPSS [group P]). Spec cPL was measured in preoperative samples (T0), 4 days (T1) and 1 (T2) and 3- to 6-months (T3) after surgery. RESULTS: Spec cPL was within reference interval (<200 µg/L) at all timepoints except at T1. At T1, 2 dogs in group M (321 and >2000 µg/L) and also 1 in group C (688 µg/L) and 1 in group P (839 µg/L) had increased spec cPL concentrations. No differences in spec cPL concentrations between groups or changes over time were identified. CONCLUSIONS AND CLINICAL IMPORTANCE: Spec cPL is not consistently increased in dogs that develop MAPSS after cEHPSS attenuation and has no potential as a biomarker for the identification of MAPSS after cEHPSS attenuation.

Dogs with congenital extrahepatic portosystemic shunts that have persistent shunting after surgery have a higher prevalence of urolithiasis.

OBJECTIVE: To report the presence of urolithiasis in dogs long-term after gradual attenuation of congenital extrahepatic portosystemic shunts (cEHPSS). ANIMALS: 25 client-owned dogs that underwent gradual attenuation of a cEHPSS, of which 19 had a closed cEHPSS and 6 developed multiple acquired portosystemic shunts (MAPSS) following surgery. PROCEDURES: A retrospective study with prospective follow-up was performed. Dogs that underwent cEHPSS surgery and had their postoperative cEHPSS status determined by transsplenic portal scintigraphy or CT angiography 3 months postoperatively were prospectively contacted and invited for a long-term follow-up visit (a minimum of 6 months postoperatively). Retrospective data were collected, and during the prospective follow-up visit a thorough history, blood tests and urinalysis, and ultrasonography of the urinary tract were performed to assess the presence of urinary signs and urolithiasis. RESULTS: Of 25 included dogs, 1 of 19 (5%) dogs with closed cEHPSS and 4 of 6 (67%) dogs with MAPSS had urolithiasis at long-term follow-up. Three (50%) dogs with MAPSS developed new uroliths. Long-term, dogs with closed cEHPSS that initially presented with and without urolithiasis had significantly less urolithiasis compared to dogs with MAPSS (P = .013 and P = .010, respectively). In the 4 dogs with closed cEHPSS that initially presented with nephrolithiasis, nephroliths became smaller or were no longer visible at the long-term follow-up visit. CLINICAL RELEVANCE: Dogs that developed MAPSS following cEHPSS surgery are at greater risk of urolithiasis compared to those with closed cEHPSS. Furthermore, ammonium urate uroliths might dissolve if portosystemic shunting ceases to exist.

Reference interval, longitudinal variability and reliability of activated clotting time in healthy dogs using a point-of-care analyser.

BACKGROUND: Activated clotting times (ACTs) are used to screen for coagulopathies and monitor heparin therapy. OBJECTIVES: To determine a reference interval (RI) for ACT in dogs using a point-of-care analyser, to quantify intra-subject within- and between-day variability, to quantify analyser reliability and inter-analyser agreement and to study the influence of a delay in measurement. METHODS: Forty-two healthy dogs were included. Measurements were performed on fresh venous blood using the i-STAT 1 analyser. The RI was determined using the Robust method. Intra-subject within-day variability and between-day variability were quantified between baseline and 2 h (n = 8) or 48 h (n = 10) later. Analyser reliability and inter-analyser agreement were studied by duplicate measurements (n = 8) on identical analysers. The influence of measurement delay was studied before and after a delay of one analytical run (n = 6). RESULTS: Mean, lower and upper reference limits for ACT were 92.9 ± 9.1, 74.4 and 111.2 s, respectively. Coefficients of variation of intra-subject within- and between-day variability were 8.1% and 10.4%, respectively, resulting in a significant between-day measurement difference. Analyser reliability assessed by the intraclass correlation coefficient and coefficient of variation were 0.87% and 3.3%, respectively. Significantly lower ACT values were observed after a measurement delay compared to direct analysis. CONCLUSIONS: Our study provides an RI for ACT in healthy dogs using the i-STAT 1 and suggests low intra-subject within- and between-day variability. Analyser reliability and inter-analyser agreement were good; however, analysis delay and between-day differences could significantly influence ACT results.

Ultrasound-guided core needle biopsy in dogs with thyroid carcinoma.

Currently, a histological diagnosis of highly vascularized canine (c) thyroid carcinoma (TC) is primarily obtained following excisional biopsy (EB) through thyroidectomy. Non-EBs are contraindicated in unresectable invasive cTCs due to their highly vascularized nature, which subsequently, lack histological diagnosis. We hypothesised ultrasound-guided core needle biopsy (UGCNB) to be a safe biopsy technique to obtain an accurate histological diagnosis in unresectable TCs. Nine client-owned dogs with suspected naturally occurring TC, presented for surgical excision, were included. First, a UGCNB was taken from the cervical tumour, followed by EB. Haemorrhage following UGCNB was evaluated preoperatively and once the tumour was surgically exposed by visual inspection and ultrasonography. Histological analysis, including cell organisation, tumour capsular and vascular invasion, and immunohistochemistry were performed and compared between both biopsy specimens (i.e., UGCNB and EB) of the same dog. Pre- and peroperative visual inspection revealed minor, localised haemorrhage, subsequent to the UGCNB, in 7/9 dogs. Histology of the EBs confirmed TC in 8/9 dogs and was inconclusive in 1/9 dogs. Histology of the UGCNBs revealed neoplastic thyroid tissue in 7/9 UGCNBs and was inconclusive in 1/9 UGCNBs. The remaining UGCNB contained no mass related tissue and was, therefore, excluded. Histological parameters (i.e., cell organisation, tumour capsular and vascular invasion) were not concordant between 6/8 included UGCNBs and their respective EB. Immunolabelling for thyroglobulin and calcitonin was concordant between all eight included UGCNBs and their respective EB. The remaining evaluated immunohistochemical markers (i.e., cyclooxygenase-2 [COX-2], P-glycoprotein and vascular endothelial growth factor [VEGF]) were concordant between the included UGCNBs and the EBs in 6/8 dogs. To conclude, UGCNBs can be safely obtained in suspected cTCs and enable a reliable diagnosis of the thyroid origin, thyroid cell origin and potential therapeutic markers such as COX-2, P-glycoprotein and VEGF. Subsequently, UGCNB enables clinicians to establish an individually tailored treatment plan in dogs with unresectable TC.

Comparison of urethral length and orifice diameter in cats undergoing transpelvic or subpubic urethrostomy for perineal urethrostomy revision (cadaveric study).

OBJECTIVES: Stenosis is a postoperative complication reported in 12-17% of male cats that undergo perineal urethrostomy (PU). This study compared two different revision techniques for failed perineal urethrostomies. The first objective was to evaluate the feasibility of performing a transpelvic urethrostomy (TPU) after a previous, correctly performed PU in male cats. The second objective was to determine the residual urethral length, orifice diameter, and the position of the orifice relative to the pubic brim and anus after PU, TPU and subpubic urethrostomy (SPU). METHODS: Twenty male cat cadavers were randomly divided into two groups: TPU and SPU. In group TPU, PU was followed by TPU; in group SPU, PU was followed by SPU. After each procedure, the urethral orifice cross-section size was estimated by inserting the largest possible urinary catheter without resistance. Residual urethral length was measured both on contrast radiographs and after anatomical dissection. RESULTS: In all cats, TPU could be performed following a technically correct PU. The TPU resulted in a 1.5-times longer residual urethral length than SPU, based on contrast radiographs (P = 0.001) and confirmed by anatomical dissection (P <0.001). Relative to the initial urethral length, PU, TPU and SPU resulted in a reduction of 24%, 36% and 56%, respectively. The urethral orifice diameter after TPU did not differ from SPU (P = 1.000), and it was not statistically significantly different between TPU and PU (P = 0.317) or between SPU and PU (P = 0.655). The urethral orifice was located further away from the pubis (P <0.001) and closer to the anus (P <0.001) after TPU than after SPU. CONCLUSIONS AND RELEVANCE: Both TPU and SPU are possible revision surgeries following PU. As TPU preserves a significantly longer urethral length and requires less tissue dissection, the risk of urinary tract infections, urinary dermatitis and urinary incontinence might be less following TPU than SPU.

Intraoral approach for zygomatic sialoadenectomy in dogs: An anatomical study and three clinical cases.

OBJECTIVE: To describe an intraoral approach (IOA) for zygomatic sialadenectomy in dogs and to compare this surgical approach to a modified lateral orbitotomy approach (LOA). STUDY DESIGN: Cadaveric study and short case series. SAMPLE POPULATION: Ten canine cadavers and three dogs with clinical disease. METHODS: Bilateral zygomatic sialoadenectomies were performed in six mesocephalic, two brachycephalic and two dolichocephalic cadavers, randomly assigned to IOA on one side and LOA on the contralateral side. Duration of surgery, ease of surgical stage scores (rated on 5-point Likert scale) and completeness of gland removal were recorded. Additionally, IOA was performed in three dogs with zygomatic salivary gland (ZSG) disease. RESULTS: Removal of the ZSG was complete in 8/10 and 10/10 dogs using the IOA and LOA, respectively. Surgery was faster with IOA (42.0 min; 33.5-49.6 min) than LOA (65.7 min; 54.9-76.4 min, p = .005). Ease of removal did not differ between approaches (p = .091). Diseased ZSGs were successfully removed in three dogs without intra- or short-term postoperative complications. CONCLUSIONS: The intraoral approach described here was technically equally challenging but faster than the LOA. Its clinical use led to an uneventful surgery with excellent short-term outcome in three dogs. CLINICAL RELEVANCE: The IOA provides an alternative approach for zygomatic sialoadenectomy in dogs with ZSG disease.

Shear wave elastography measurements in dogs treated surgically for congenital extrahepatic portosystemic shunts.

Assessing the postoperative surgical success of congenital extrahepatic portosystemic shunt (EHPSS) attenuation can be challenging and involve invasive imaging methods. Elastography is an ultrasound technique that allows qualitative and quantitative estimation of tissue stiffness and has extensively been used in people with liver disease. In recent years, increased interest in this technique has developed in veterinary medicine due to its non-invasive nature, availability, and low cost. The objective of this study was to compare liver stiffness values between dogs with closed EHPSS and those with multiple acquired portosystemic shunts (MAPSS) after gradual surgical attenuation and to assess whether shear wave elastography could be used to determine EHPSS closure. As a secondary objective, measurements obtained from both intercostal and subxiphoidal views were compared. Mean values for the average, median, and maximum two-dimensional shear wave velocities (2D SWV) for the closed EHPSS were 2.88 +/-0.11 m/s; 2.83 +/-0.11 m/s; and 3.75 +/-0.16 m/s, respectively. In the MAPSS dogs, mean values for the average, median, and maximum 2D SWV were 2.77 +/- 0.17 m/s; 2.71 +/- 0.17 m/s; and 3.66 +/-0.24 m/s, respectively. No significant differences in 2D SWV were present between dogs with closed EHPSS and those with MAPSS (P = 0.33; P = 0.33; P = 0.42, respectively). When assessing potential differences between intercostal and subxiphoidal 2D SWV measurements, no effect was observed for the average and median 2D SWV (P = 0.06; P = 0.07, respectively). Yet, a significant difference was identified for the maximum 2D SWV between intercostal 4.00 +/-0.20 m/s and subxiphoidal 3.41 +/-0.17 m/s measurements (P = 0.02). The relevance of this finding is uncertain as many other studies about liver elastography only report mean and not maximum values.

B-Mode and Contrast-Enhanced Ultrasonography Aspects of Benign and Malignant Superficial Neoplasms in Dogs: A Preliminary Study.

Contrast-enhanced ultrasonography (CEUS) is considered a promising technique for differentiation of benign and malignant tumors in humans. However, few studies have assessed superficial neoplasms in dogs by means of CEUS. The aim of this study was to identify ultrasonographic criteria evaluated by B-mode ultrasound (US) and CEUS that may be used to distinguish benign and malignant superficial neoplasms in dogs. A total of 63 superficial neoplasms from 59 dogs were evaluated using B-mode US and CEUS prior to histopathologic examination. Qualitative and quantitative parameters were compared between benign and malignant neoplasms by Fischer's exact test or fixed effects model. With B-mode US, a significant difference was found for border definition, echogenicity and echotexture. With CEUS, a significant difference was found for the enhancement pattern at wash-in and the wash-out area under the curve at the center of the neoplasm. Malignant neoplasms had on average a lower regional blood volume during the wash-out phase compared to benign neoplasms. Despite these significant differences, there was a considerable overlap in B-mode and CEUS parameters between benign and malignant neoplasms. In conclusion, B-mode US and CEUS might contribute to malignancy prediction; however, based on individual ultrasonographic parameters, they seem unable to replace cytology or histopathology.

Comparison of serum tryptase as a diagnostic oncological marker in canine versus human mast cell neoplasms.

Canine mast cell tumors (MCTs) are a promising translational model for human mast cell neoplasms with striking similarities such as the Darier's sign and mutations in the KIT gene. Whereas mast cell neoplasms are rare in humans, MCTs are the most frequent malignant neoplasms of the skin in dogs. In human systemic mastocytosis, serum tryptase is an important diagnostic criterion. Surprisingly, serum tryptase levels were not yet investigated in dogs with MCTs. Therefore, the aim of this study was to investigate whether serum tryptase levels in dogs with cutaneous MCTs were elevated compared to those of a non-MCT control group. As a secondary aim, it was investigated whether surgical manipulation caused an increase in serum tryptase in canine MCT patients. A total of 48 serum samples were collected from dogs with different grades of cutaneous MCTs (n = 24) and non-MCT controls (n = 24). In dogs with cutaneous MCTs, blood was collected prior to and within 1 h after surgery. Serum tryptase levels were measured using a commercially available canine-specific ELISA kit. No significant difference in serum tryptase levels was found between cutaneous MCT patients and non-MCT controls, nor in these levels before versus after surgery. Our findings in canine cutaneous MCTs are in accordance with human cutaneous mastocytosis, where serum tryptase levels tend to remain within the normal range. However, despite various similarities between aggressive mast cell tumors in dogs and humans, serum tryptase cannot be considered a diagnostic biomarker in dogs with cutaneous MCTs as part of a comparative oncologic strategy.

Evaluation of different blood tests in dogs with extrahepatic portosystemic shunts to assess shunt closure after surgical treatment.

OBJECTIVE: To determine the sensitivity and specificity of different individual and combined blood tests to assess extrahepatic portosystemic shunt (EHPSS) closure after gradual attenuation of EHPSS in dogs. STUDY DESIGN: Clinical prospective study. ANIMALS: Twenty client-owned dogs with EHPSS. METHODS: Fasting ammonia (FA), preprandial, postprandial, and paired serum bile acids (SBA), the lidocaine/monoethylglycylxylidide (L/MEGX) test, and serum hyaluronic acid (SHA) were performed at diagnosis, and 1, 3, and 6 months postoperatively. Transsplenic portal scintigraphy was performed to determine EHPSS closure 3 months postoperatively. Their sensitivity and specificity in determining shunt closure postoperatively were calculated. RESULTS: When assessing a single blood parameter, FA had the highest specificity (100%), whereas SHA and MEGX measured 15 min after lidocaine administration (T15) had the highest sensitivity (96.9% and 96.2%, respectively) for determining shunt closure postoperatively. The most promising blood test combinations were SHA (sensitivity 96.9%, specificity 81.8%), combined with the L/MEGX test (MEGX at T15: sensitivity 100%, specificity 72.4%) or the L/MEGX test (MEGX at T15) combined with either FA (sensitivity 100%, specificity 82.8%) or postprandial SBA (sensitivity 100%, specificity 81.5%). CONCLUSION: Both SHA and the L/MEGX test were sensitive tests for determining shunt closure after gradual attenuation of EHPSS. Test performances could even be improved by combining these tests with each other or with traditional tests such as FA or postprandial SBA. CLINICAL SIGNIFICANCE: Although SHA and the L/MEGX test are sensitive blood tests for determining EHPSS closure, especially when combined with traditional blood tests, imaging is still needed to confirm EHPSS closure.

Comparison of diet, lactulose, and metronidazole combinations in the control of pre-surgical clinical signs in dogs with congenital extrahepatic portosystemic shunts.

BACKGROUND: Hepatic supportive diet (HSD), lactulose, and antimicrobials are medical treatments for dogs with congenital extrahepatic portosystemic shunts (cEHPSS). The relative contribution of these treatment components is currently unknown. OBJECTIVES: To determine which treatment combinations are most efficacious in pre-surgical control of clinical signs of cEHPSS in dogs. ANIMALS: Thirty-six dogs with untreated cEHPSS. METHODS: Three-arm randomized clinical trial. At inclusion (T0), dogs were divided into 3 groups: HSD (n = 12), HSD + lactulose (n = 12), or HSD + metronidazole (n = 12) and received the randomized treatment for 4 weeks (T1) followed by combined treatment of HSD + lactulose + metronidazole for 2 weeks or until cEHPSS attenuation (T2). Clinical score as well as fasting ammonia (FA) and C-reactive protein (CRP) concentrations were compared among groups and time points. RESULTS: Thirty-four dogs were evaluated. Thirty-four dogs reached T1 and 29 dogs T2. At T1, clinical scores decreased in the HSD + lactulose (n = 11; P = .001), but not in the HSD (n = 8; P = .96) and HSD + metronidazole (n = 10; P = .06) groups. Adding metronidazole to HSD + lactulose (n = 11) did not result in further clinical score improvement (T2; P = 1.000). Moderate and weak correlation between clinical score and FA and clinical score and CRP was present (ρ = .35, P < .001; ρ = .27, P = .01, respectively) with FA decreasing over time on medical treatment (P = .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Combined HSD + lactulose seems sufficient for pre-surgical cEHPSS stabilization unlike sole HSD or HSD + metronidazole. Medical treatment of cEHPSS clinical signs decreases FA.

Total lipid concentration of hairs increases after successful attenuation of extrahepatic portosystemic shunts in dogs.

BACKGROUND: Skin and coat quality can reflect nutritional deficiencies in humans and dogs with liver diseases. HYPOTHESIS/OBJECTIVES: Determine skin and coat quality based on a scoring protocol and skin biopsies in dogs with an extrahepatic portosystemic shunt (EHPSS), and determine total lipid concentrations in hairs of dogs at time of surgery and 3 months after successful shunt closure. ANIMALS: Ten client-owned dogs that underwent successful gradual attenuation of EHPSS, as defined by transsplenic portal scintigraphy, were included. MATERIALS AND METHODS: A prospective cohort study was performed. All dogs underwent gradual attenuation of the EHPSS. Skin and coat scoring was performed at diagnosis, surgery, and 1 and 3 months postoperatively. Hair was plucked from the lumbar region for total lipid analysis and an 8 mm punch skin biopsy was taken at time of surgery and 3 months postoperatively, when the dogs underwent transsplenic portal scintigraphy to determine EHPSS closure. RESULTS: No significant differences were observed in skin and coat scoring over time. Total lipid concentrations of hairs increased significantly from surgery to 3 months postoperatively [30 µg/mg hair (13-56 µg/mg hair) to 47 µg/mg hair (25-63 µg/mg hair); p = 0.005]. Skin biopsies showed the presence of significantly more scales 3 months postoperatively (p = 0.018). CONCLUSIONS AND CLINICAL RELEVANCE: A significant increase in total lipid concentrations in hairs suggests that successful surgical attenuation of EHPSS improves either intestinal absorption of lipids, fat metabolism in the liver, or a combination of both.

Contexte - La qualité de la peau et du pelage peut refléter des carences nutritionnelles chez les humains et les chiens atteints de maladies du foie. Hypothèse/Objectifs - Déterminer la qualité de la peau et du pelage sur la base d'un protocole de notation et de biopsies cutanées chez les chiens avec un shunt portosystémique extrahépatique (EHPSS), et déterminer les concentrations totales de lipides dans les poils des chiens au moment de la chirurgie et trois mois après la fermeture réussie du shunt. Animaux - Dix chiens appartenant à des clients qui ont subi une atténuation progressive réussie de l'EHPSS, telle que définie par la scintigraphie portale trans-splénique, ont été inclus. Matériels et méthodes - Une étude de cohorte prospective a été réalisée. Tous les chiens ont subi une atténuation progressive de l'EHPSS. Une notation de la peau et du pelage a été réalisée au moment du diagnostic, de la chirurgie et un et trois mois après l'opération. Les cheveux ont été prélevés dans la région lombaire pour une analyse des lipides totaux et une biopsie cutanée à l'emporte-pièce de 8 mm a été effectuée au moment de la chirurgie et trois mois après l'opération, lorsque les chiens ont subi une scintigraphie portale trans-splénique pour déterminer la fermeture de l'EHPSS. Résultats - Aucune différence significative n'a été observée dans la notation de la peau et du pelage au fil du temps. Les concentrations totales de lipides dans les poils ont augmenté de manière significative entre la chirurgie et trois mois après l'opération [30 µg/mg de poils (13-56 µg/mg de poils) à 47 µg/mg de poils (25-63 µg/mg de poils) ; P = 0,005]. Les biopsies cutanées ont montré la présence de significativement plus d'écailles trois mois après l'opération (P = 0,018). Conclusions et pertinence clinique - Une augmentation significative des concentrations totales de lipides dans les cheveux suggère qu'une atténuation chirurgicale réussie de l'EHPSS améliore soit l'absorption intestinale des lipides, soit le métabolisme des graisses dans le foie, soit une combinaison des deux.

Introducción- la calidad de la piel y el pelaje puede reflejar deficiencias nutricionales en humanos y perros con enfermedades hepáticas. Hipótesis/Objetivos- determinar la calidad de la piel y el pelaje según un protocolo de valoración y en biopsias de piel en perros con shunt portosistémico extrahepática (EHPSS) y determinar las concentraciones totales de lípidos en el pelo de los perros en el momento de la cirugía y tres meses después del tratamiento exitoso del shunt. Animales- se incluyeron diez perros de propietarios particulares que se sometieron a una atenuación gradual exitosa de EHPSS, según se identificó mediante por gammagrafía portal transesplénica. Materiales y métodos - Se realizó un estudio de cohorte prospectivo. A todos los perros se les realizó una atenuación gradual del EHPSS. La valoración de la piel y el pelaje se realizó en el momento del diagnóstico, la cirugía y uno y tres meses después de la operación. Se arrancó el pelo de la región lumbar para el análisis de lípidos totales y se tomó una biopsia de piel con sacabocados (punch) de 8 mm en el momento de la cirugía y tres meses después de la operación, cuando los perros se sometieron a una gammagrafía portal transesplénica para determinar el cierre de EHPSS. Resultados- no se observaron diferencias significativas en la valoración de la piel y el pelaje a lo largo del tiempo. Las concentraciones de lípidos totales del pelo aumentó significativamente desde la cirugía hasta los tres meses posteriores a la operación [30 µg/mg de pelo (13-56 µg/mg de pelo) a 47 µg/mg de cabello (25-63 µg/mg de pelo); P = 0,005]. Las biopsias de piel mostraron la presencia de mayor cantidad de escamas de forma significativa tres meses después de la operación (P = 0,018). Conclusiones y relevancia clínica- un aumento significativo en las concentraciones de lípidos totales en el pelo sugiere que la atenuación quirúrgica exitosa de EHPSS mejora la absorción intestinal de lípidos, el metabolismo de las grasas en el hígado o una combinación de ambos.

Contexto - A qualidade da pele e dos pelos pode refletir deficiências nutricionais em humanos e cães com hepatopatias. Hipótese/Objetivos - Determinar a qualidade da pele e pelos baseada em um protocolo de escore e biópsias cutâneas em cães com shunt portossistêmico extra-hepático (EHPSS) e determinar as concentrações lipídicas totais nos pelos de cães no momento da cirurgia e três meses após o fechamento bem-sucedido do shunt. Animais - Foram incluídos dez cães de proprietários submetidos à atenuação gradual do EHPSS bem-sucedida, confirmada por cintilografia portal transesplênica. Materiais e métodos - Realizou-se um estudo de coorte prospectivo. Todos os cães foram submetidos à atenuação gradual do EHPSS. A classificação de pele e pelos em escores foi realizada no diagnóstico, cirurgia, e com um e três meses de pós-operatório. Os pelos foram arrancados da região lombar para análise lipídica total e uma biópsia com punch de 8mm foi coletada no momento da cirurgia e com três meses de pós-operatório, quando os cães foram submetidos à cintilografia portal transesplênica para determinar o fechamento do EHPSS. Resultados - Não foram observadas diferenças significativas nos escores de pele e pelos ao longo do tempo. As concentrações de lipídicas totais aumentaram significativamente da cirurgia aos três meses de pós-operatório [30 µg/mg de pelo (13-56 µg/mg pelo) para 47 µg/mg de pelo (25-63 µg/mg de pelo); P = 0,005]. As biópsias cutâneas revelaram a presença de significativamente mais escamas com três meses de pós-operatório (P = 0,018). Conclusões e relevância clínica - O aumento significativo de concentrações lipídicas totais nos pelos sugere que a atenuação cirúrgica de EHPSS bem-sucedida melhora tanto a absorção intestinal de lipídeos quanto o metabolismo de gordura no fígado, ou uma combinação dos dois.

Diagnostic value of liver function tests and ultrasonography in dogs with suspected congenital portosystemic shunts.

BACKGROUND: Diagnosing a congenital portosystemic shunt (cPSS) in dogs can be challenging. The current study aims to report diagnostic performance of fasting ammonia (FA), preprandial, postprandial and paired serum bile acids (SBA) and abdominal ultrasound (aUS) in dogs suspected of having a cPSS. METHODS: Medical records of dogs suspected of having a cPSS at initial presentation were retrospectively reviewed. RESULTS: In total, 192 dogs suspected of cPSS were included: a cPSS was confirmed in 147 dogs and excluded in 45 dogs. FA had the best combined sensitivity and specificity (77.4 and 93.3%, respectively) to diagnose cPSS. The sensitivity and negative predictive value were 100.0% for paired SBA, making paired SBA the best test to exclude cPSS in this population. Sensitivity and specificity of aUS were 80.8 and 90.0%, respectively. CONCLUSIONS: In dogs with clinical signs compatible with cPSS, elevated FA is suggestive of cPSS, whereas normal paired SBA makes the presence of a cPSS unlikely. Although aUS is a useful tool to diagnose cPSS, additional imaging is required to visualize cPSS in almost 20% of cases. Furthermore, the localisation of cPSS can be misdiagnosed, especially in case of extrahepatic cPSS that do not insert into the prehepatic vena cava.

Persistent hypercobalaminemia three months after successful gradual attenuation of extrahepatic shunts in dogs: a prospective cohort study.

BACKGROUND: Deficiencies in vitamin A and D and disorders in the vitamin B complex are often present in people with chronic liver diseases. So far, the serum concentrations of these vitamins have not yet been studied in dogs with congenital extrahepatic portosystemic shunts (EHPSS), who also have some degree of liver dysfunction. The objective was to assess serum vitamin concentrations in dogs with EHPSS from diagnosis to complete closure. A prospective cohort study was performed using ten client-owned dogs with EHPSS, closed after gradual surgical attenuation. Serum concentrations of vitamin A, 25-hydroxyvitamin D, folic acid, cobalamin and methylmalonic acid (MMA) were measured at diagnosis prior to institution of medical therapy, prior to surgery, and three months after gradual attenuation and complete closure of the EHPSS. RESULTS: At diagnosis, median serum concentrations of vitamin A, 25-hydroxyvitamin D and folic acid were 18.2 µg/dL (8.8 - 79.5 µg/dL), 51.8 ng/mL (19.4 - 109.0 ng/mL), and 8.1 µg/L (5.2 - 14.5 µg/L), respectively, which increased significantly postoperatively (88.3 µg/dL (51.6 - 182.2 µg/dL, P=0.005), 89.6 ng/mL (49.3 - >150.0 ng/mL, P =0.005), and 14.8 µg/L (11.5 - 17.7 µg/L, P <0.001), respectively). Median serum cobalamin concentrations were 735.5 ng/L (470 - 1388 ng/L) at diagnosis and did not significantly decrease postoperatively (P =0.122). Both at diagnosis and three months postoperatively 7/10 dogs had hypercobalaminemia. CONCLUSIONS: Serum concentrations of vitamin A, 25-hydroxyvitamin D and folic acid significantly increase after surgical attenuation. Nevertheless, persistent hypercobalaminemia is suggestive of ongoing liver dysfunction, despite successful surgery.

Shear wave elastography of lymph nodes in dogs with head and neck cancer: A pilot study.

Shear wave elastography (SWE) is a novel ultrasound imaging technique, used in human medicine to differentiate metastatic from non-metastatic lymph nodes (LNs) based on higher tissue stiffness. The objective of this pilot study was to evaluate whether canine metastatic LNs were stiffer compared to non-metastatic LNs. SWE of sentinel or regional LNs in dogs with head and neck cancer was performed. Ten elastograms of each LN were acquired. In each elastogram, mean, median, and maximum shear wave velocities (SWVs) were calculated in the most elastic region, the stiffest region, and the entire LN. The means of those SWVs for each region of each LN were subsequently calculated. Furthermore, a stepwise subsampling was performed to assess the effect of the number of acquired elastograms on the consistency of the classification of a LN as metastatic or not. Twenty-four LNs in 15 dogs with head and neck cancer were included, of which 10 LNs were metastatic. Metastatic medial retropharyngeal and mandibular LNs were successfully distinguished from non-metastatic LNs based on higher mean and median SWVs in the stiffest region and higher maximum SWVs in entire LNs. Furthermore, maximum SWVs in the stiffest region of mandibular LNs were higher in metastatic LNs compared to non-metastatic LNs. Downstream analyses demonstrated that at least eight elastograms were necessary to perform reliable analyses. This pilot trial demonstrated that SWE has potential to discriminate metastatic from non-metastatic LNs; however, LN status should be based on at least eight elastograms in future clinical trials.

Influence of age, sex, body condition score, rectal temperature, anatomical location and hair on skin pH in dogs.

BACKGROUND: Physiological skin pH levels are well-documented in human medicine, and assessment of variations may be important in assessing the efficacy of wound healing. By contrast, physiological skin pH levels in dogs are sparsely described. HYPOTHESIS/OBJECTIVES: To determine the pH of intact skin in healthy dogs and to study the influence of different physiological factors on the pH level of canine skin. ANIMALS: Seventy-seven client-owned dogs of various breeds, age and sex. METHODS AND MATERIALS: A prospective study was designed and the pH of intact skin was measured at the concave surface of both pinnae, and in both axillary and inguinal regions. For each location, the colour and density of the hairs also was recorded. Each dog's rectal body temperature and body condition scores also were determined. RESULTS: The skin pH in dogs <12 weeks of age was significantly lower (3.97-5.70) than in older dogs (4.40-8.18) (P < 0.001). In dogs >12 weeks of age, skin pH was significantly lower in the inguinal regions compared to the pinnae (P = 0.008), and female dogs had a significantly lower skin pH in the inguinal regions than male dogs (P = 0.043). Pinnae covered with light-coloured hair had a lower skin pH than those with dark-coloured hair (P = 0.04). No significant differences were found between dogs with different body condition scores, body temperatures or differences in hair density. CONCLUSIONS AND CLINICAL RELEVANCE: The pH of intact healthy skin is lower in puppies of <12 weeks of age. Regional differences of body location also were seen which were variably affected by hair colour and sex. A baseline assessment of skin pH in healthy dogs is important for future studies of disease and wound healing.

Plasma amino acid profiles in dogs with closed extrahepatic portosystemic shunts are only partially improved 3 months after successful gradual attenuation.

BACKGROUND: Dogs with portosystemic shunts have an altered blood amino acid profile, with an abnormal branched-chained amino acid (BCAA)-to-aromatic amino acid (AAA) ratio being the most common abnormality. Different liver diseases have distinctive amino acid profiles. OBJECTIVES: Determine the changes in plasma amino acid profiles in dogs with extrahepatic portosystemic shunts (EHPSS) from diagnosis to complete closure. ANIMALS: Ten client-owned dogs with EHPSS closed after surgical attenuation. METHODS: Prospective cohort study. Medical treatment was instituted in dogs diagnosed with EHPSS. At least 4 weeks later, gradual surgical attenuation was performed. Three months postoperatively, EHPSS closure was confirmed by transsplenic portal scintigraphy. Clinical signs were scored and blood was taken before institution of medical treatment, at time of surgery, and 3 months postoperatively. At the end of the study, the plasma amino acid profiles were analyzed in batch. RESULTS: The median BCAA-to-AAA ratio was extremely low (0.6) at time of diagnosis and remained low (0.5) at time of surgery, despite the fact that median neurological score significantly improved from 22 to 2 after starting medical treatment (P = .04). Three months after surgical attenuation, a significantly higher BCAA-to-AAA ratio (1.5) was observed (P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Medical treatment does not improve the BCAA-to-AAA ratio in dogs with EHPSS, despite substantial clinical improvement. Although the ratio significantly increased after EHPSS closure, it was still indicative of moderate to severe hepatic dysfunction in all dogs.

Cytosolic delivery of gadolinium via photoporation enables improved in vivo magnetic resonance imaging of cancer cells.

Longitudinal in vivo monitoring of transplanted cells is crucial to perform cancer research or to assess the treatment outcome of cell-based therapies. While several bio-imaging techniques can be used, magnetic resonance imaging (MRI) clearly stands out in terms of high spatial resolution and excellent soft-tissue contrast. However, MRI suffers from low sensitivity, requiring cells to be labeled with high concentrations of contrast agents. An interesting option is to label cells with clinically approved gadolinium chelates which generate a hyperintense MR signal. However, spontaneous uptake of the label via pinocytosis results in its endosomal sequestration, leading to quenching of the T1-weighted relaxation. To avoid this quenching effect, delivery of gadolinium chelates directly into the cytosol via electroporation or hypotonic cell swelling have been proposed. However, these methods are also accompanied by several drawbacks such as a high cytotoxicity, and changes in gene expression and phenotype. Here, we demonstrate that nanoparticle-sensitized laser induced photoporation forms an attractive alternative to efficiently deliver the contrast agent gadobutrol into the cytosol of both HeLa and SK-OV-3 IP1 cells. After intracellular delivery by photoporation the quenching effect is clearly avoided, leading to a strong increase in the hyperintense T1-weighted MR signal. Moreover, when compared to nucleofection as a state-of-the-art electroporation platform, photoporation has much less impact on cell viability, which is extremely important for reliable cell tracking studies. Additional experiments confirm that photoporation does not induce any change in the long-term viability or the migratory capacity of the cells. Finally, we show that gadolinium 'labeled' SK-OV-3 IP1 cells can be imaged in vivo by MRI with high soft-tissue contrast and spatial resolution, revealing indications of potential tumor invasion or angiogenesis.