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1.
J Vet Intern Med ; 38(2): 971-979, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38348783

RESUMEN

BACKGROUND: Hypertriglyceridemia (HTG) is prevalent in Miniature Schnauzers, predisposing them to life-threatening diseases. Varied responses to management strategies suggest the possibility of multiple subtypes. HYPOTHESIS/OBJECTIVE: To identify and characterize HTG subtypes in Miniature Schnauzers through cluster analysis of lipoprotein profiles. We hypothesize that multiple phenotypes of primary HTG exist in this breed. ANIMALS: Twenty Miniature Schnauzers with normal serum triglyceride concentration (NTG), 25 with primary HTG, and 5 with secondary HTG. METHODS: Cross-sectional study using archived samples. Lipoprotein profiles, generated using continuous lipoprotein density profiling, were clustered with hierarchical cluster analysis. Clinical data (age, sex, body condition score, and dietary fat content) was compared between clusters. RESULTS: Six clusters were identified. Dogs with primary HTG were dispersed among 4 clusters. One cluster showed the highest intensities for triglyceride-rich lipoprotein (TRL) and low-density lipoprotein (LDL) fractions and also included 4 dogs with secondary HTG. Two clusters had moderately high TRL fraction intensities and low-to-intermediate LDL intensities. The fourth cluster had high LDL but variable TRL fraction intensities with equal numbers of NTG and mild HTG dogs. The final 2 clusters comprised only NTG dogs with low TRL intensities and low-to-intermediate LDL intensities. The clusters did not appear to be driven by differences in the clinical data. CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this study support a spectrum of lipoprotein phenotypes within Miniature Schnauzers that cannot be predicted by triglyceride concentration alone. Lipoprotein profiling might be useful to determine if subtypes have different origins, clinical consequences, and response to treatment.


Asunto(s)
Enfermedades de los Perros , Hiperlipidemias , Hipertrigliceridemia , Perros , Animales , Estudios Transversales , Hipertrigliceridemia/veterinaria , Hiperlipidemias/veterinaria , Lipoproteínas , Triglicéridos , Análisis por Conglomerados
2.
Vet Clin Pathol ; 52(2): 243-251, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37127847

RESUMEN

BACKGROUND: There are few reports in dogs that have evaluated the utility of semi-quantitative scoring of bone marrow iron stores in conjunction with reticulocyte hemoglobin (CHr) to identify iron-restricted erythropoiesis due to absolute iron deficiency or iron sequestration. OBJECTIVES: An established system for scoring iron stores in human bone marrow samples was applied to dogs. The objectives were to evaluate interobserver agreement (Κω ), determine marrow iron scores in dogs without detectable hematologic abnormalities, and assess combined interpretation of iron scores and CHr to evaluate for iron-restricted erythropoiesis. METHODS: Four blinded observers independently scored iron in 139 Prussian blue-stained canine marrow samples from 0 (none) to 6 (very heavy), including healthy controls (n = 12), clinically ill dogs with (n = 100) and without (n = 16) detectable hematologic abnormalities, and dogs with experimental nutritional iron deficiency (n = 11). Additional medical record data were available for 118 dogs to evaluate for other evidence of iron deficiency (abnormal CHr, RBC indices, serum iron variables, external blood loss, or nutritional deficiencies). RESULTS: Mean Κω was 0.69 (substantial agreement) for all samples but was 0.44 (moderate agreement) for samples with iron scores <3, indicating distinguishing scores 0-2 may not be reliable. Dogs without detectable hematologic abnormalities had scores from 3-5. Dogs with scores <3 and decreased CHr often had more indicators of iron deficiency vs dogs only having low iron scores or low CHr. CONCLUSIONS: Evaluation of dogs with marrow iron score <3 for external blood loss or nutritional deficiencies is likely clinically worthwhile, particularly if there is also decreased CHr.


Asunto(s)
Anemia Ferropénica , Enfermedades de los Perros , Deficiencias de Hierro , Desnutrición , Humanos , Perros , Animales , Hierro , Eritropoyesis , Médula Ósea , Anemia Ferropénica/diagnóstico , Anemia Ferropénica/veterinaria , Hemoglobinas/análisis , Deficiencias de Hierro/veterinaria , Reticulocitos/química , Desnutrición/veterinaria
3.
Toxicol Pathol ; 50(7): 883-885, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36200573

RESUMEN

The hematological impacts of a drug can affect erythropoiesis at the level of the bone marrow, or decrease the life span of the RBC (red blood cell). The most common and recognizable clinical manifestation of either type of drug-induced erythropoietic injury is a decrease in RBC mass, or what is clinically referred to as an anemia. A decrease in RBC production can generally be separated from increased destruction (hemolysis) by evaluation of the hemogram for evidence of regeneration. In most healthy mammalian species, hemolysis will result in a regenerative response characterized by an increase in circulating reticulocytes. Hemorrhage as an alternative cause of a regenerative anemia can generally be excluded by careful clinical evaluation of the animal. Subsequently, the investigation of a drug-induced regenerative anemia should involve a very thorough evaluation of RBC morphology for evidence of immune-mediated destruction, RBC oxidative injury, and fragmentation that can help to identify the underlying pathological mechanism(s) involved.


Asunto(s)
Anemia , Hemólisis , Animales , Eritrocitos/patología , Eritropoyesis , Anemia/inducido químicamente , Anemia/patología , Reticulocitos , Mamíferos
4.
Animals (Basel) ; 12(20)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36290132

RESUMEN

The clinical evaluation of lipid metabolism in equids is often limited to the measurement of total cholesterol and triglyceride concentrations. This provides a limited picture of metabolic state and general health, given the continuous exchange of lipid species between various lipoproteins. Major lipoprotein classes in equids include high-density lipoprotein (HDL), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), and chylomicrons (CM). Unlike large breed horses, donkeys are highly susceptible to hepatic lipidosis. Currently, serum triglyceride concentrations serve as a surrogate marker of hepatic lipid exportation. Both VLDL, indicative of hepatic exportation, and its metabolic end-product, LDL, are rich in triglycerides, and contribute to this value. Diagnostic assays that distinguish VLDL from LDL could be useful in better recognizing the hepatic pathology in donkeys. The compositional differences of lipoproteins across species limit the use of commercially available assays developed for the measurement of human lipoproteins in domestic animals. In this study, we evaluated a high-resolution polyacrylamide gel electrophoresis method (Lipoprint®) for separating major lipoprotein classes and sub-fractionating LDL and HDL based on particle size in a large group of donkeys, and compared the pattern to a representative set of horses. Donkeys proved an HDL-rich species, with HDL accounting for the bulk of all lipoproteins (average 78.45%, SD 6.6%, range 92.2-55%). VLDL accounted for a large portion of the total (average 21.6%, SD 6.6%, range 37.1-7.8%), with minimal amounts of LDL detected. The horses tested had higher proportions of VLDL as compared to donkeys (31.7% and 21.6%, respectively p = 0.00008). The later finding draws into question the purported relationship between VLDL, high triglycerides, and hepatic lipidosis, given the incidence of the disease in donkeys is far higher than in horses.

5.
J Vet Intern Med ; 36(3): 993-1004, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35420224

RESUMEN

BACKGROUND: Improved methodology to measure acute phase proteins and determination of lipoprotein particle-size distribution (PSD) could be clinically useful in dogs with systemic inflammatory processes. OBJECTIVES: Evaluate an immunoturbidometric assay for serum amyloid A (SAA) and lipoprotein PSD in dogs with sepsis, nonseptic systemic inflammation, and in healthy controls. Correlate dyslipidemic changes with SAA and C-reactive protein (CRP) concentrations. ANIMALS: Twenty-five dogs with sepsis, 15 dogs with nonseptic systemic inflammation, and 22 healthy controls. METHODS: Prospective, case-control study. Variables included SAA, CRP, and electrophoretic subfractionation of high- and low-density lipoproteins (HDL, LDL). Continuous variables were compared using ANOVA or Kruskal-Wallis tests with linear regression or Spearman's rank correlation used to assess relationships between variables. RESULTS: Median SAA and CRP concentrations were greater in dogs with sepsis (SAA 460 mg/L, interquartile range [IQR] 886 mg/L; CRP 133.2 mg/L, IQR 91.6 mg/L) and nonseptic inflammation (SAA 201 mg/L, IQR 436 mg/L; CRP 91.1 mg/L, IQR 88.6 mg/L) compared to healthy dogs (SAA 0.0 mg/L, IQR 0.0 mg/L; CRP 4.9 mg/L, IQR 0.0 mg/L) P < .0001. A cutoff of >677.5 mg/L SAA was 43.2% sensitive and 92.3% specific for sepsis. Low-density lipoprotein was higher in dogs with sepsis 29.6%, (mean, SD 14.6) compared to 14.4% (mean, SD 5.6) of all lipoproteins in healthy controls (P = .005). High-density lipoprotein was not associated with CRP but was negatively correlated with SAA (rs -0.47, P < .0001). Subfractions of LDL and HDL differed between groups (all P < .05). CONCLUSIONS AND CLINICAL IMPORTANCE: Measurement of SAA using the immunoturbidometric assay evaluated in this study and lipoprotein PSD in dogs with inflammation might help distinguish septic from nonseptic causes of inflammation.


Asunto(s)
Enfermedades de los Perros , Sepsis , Proteínas de Fase Aguda , Reacción de Fase Aguda/veterinaria , Animales , Biomarcadores , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Perros , Inflamación/veterinaria , Lipoproteínas , Tamaño de la Partícula , Estudios Prospectivos , Sepsis/veterinaria , Proteína Amiloide A Sérica/metabolismo
6.
Vet Clin Pathol ; 51(1): 119-125, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35224766

RESUMEN

BACKGROUND: Reference intervals (RIs) for routine clinicopathologic data in sheep are sparse. The authors sought to establish hematologic and biochemical RIs from a varied ovine population to improve data interpretation for small ruminant veterinarians. OBJECTIVES: The goal of this study was to establish ovine CBC and biochemistry reference intervals by sampling 120 healthy adult sheep, both male and female, from a variety of breeds, located in the Northeastern United States. METHODS: One hundred and eighteen sheep were included in the CBC RI and 121 sheep were included in the biochemistry panel RI. RESULTS: RIs for 42 CBC and biochemistry analytes were established in accordance with the American Society for Veterinary Clinical Pathology and Clinical Laboratory Standards Institute guidelines. CONCLUSIONS: These RIs are provided to assist small ruminant veterinarians with the interpretation of CBC and biochemistry panel results in sheep.


Asunto(s)
Hematología , Animales , Recuento de Células Sanguíneas/veterinaria , Femenino , Masculino , New England , Estándares de Referencia , Valores de Referencia , Ovinos , Estados Unidos
7.
J Vet Intern Med ; 36(2): 464-472, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35166405

RESUMEN

BACKGROUND: Current diagnostic evaluation of transudative effusions rarely aids in identifying an underlying etiology. Lipoproteins in the fluid might reflect the site or nature of vessel involvement. OBJECTIVES: Improve the classification and diagnostic utility of pleural and peritoneal transudates in dogs and cats by investigating lipoprotein patterns in effusions. Compare these patterns with other peritonaeal and pleural fluid variables and underlying diseases. ANIMALS: Samples of transudates and serum from 18 cats and 37 dogs with transudative effusion (total nucleated cell count [TNCC] <5000 cells/µL) were analyzed. METHODS: Lipoprotein fractions, triglyceride, and cholesterol (CHO) concentrations were prospectively determined in paired fluid and serum samples. Standard fluid measurements were retrospectively collected. RESULTS: Two distinct fluid lipoprotein patterns were noted. Fluids rich in VLDL+IDL were associated with chronic kidney disease, acquired portosystemic shunts or protein-losing enteropathy (group I). Fluids rich in denser lipoproteins were associated with underlying heart disease, caudal vena cava syndrome or intracavitary neoplasia (group II). Group I and group II also had significant differences between fluid concentrations of CHO (x̄ = 8 vs 110 mg/dL) and TP (x̄ = 0.6 vs 3.8 g/dL), respectively. Five peritoneal transudates were triglyceride-rich (>100 mg/dL) and associated with pancreatitis. CONCLUSIONS AND CLINICAL IMPORTANCE: Protein-poor (TP <1.5 g/dL) and protein-rich (TP >2.5 g/dL) transudates were associated with distinct lipoprotein patterns and specific groups of disease. Effusions secondary to pancreatitis might be transudative and rich in triglycerides.


Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Derrame Pleural , Animales , Enfermedades de los Gatos/diagnóstico , Gatos , Enfermedades de los Perros/diagnóstico , Perros , Exudados y Transudados , Lipoproteínas , Derrame Pleural/veterinaria , Estudios Retrospectivos
8.
Vet Immunol Immunopathol ; 242: 110339, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34715602

RESUMEN

Complement-mediated intravascular hemolysis occurs in canine immune-mediated hemolytic anemia (IMHA). Complement inhibitors might enhance treatment of this disease. Dimers of acetylsalicylic acid such as 5,5'-methylenebis(2-acetoxybenzoic acid) (DAS) have been reported to inhibit complement. This study aimed to characterize the pharmacokinetics and safety profile of a single 3 mg/kg IV dose of DAS in 6 healthy mixed-breed dogs. Serum concentrations of DAS and its primary metabolites were measured by liquid chromatography-tandem mass spectrometry at baseline and at 5, 10 and 30 min, and 1, 2, 4, 6, 8, 12, 18 and 24 h post-administration. Additional blood samples were collected 7 and 14 days after drug administration. Complete blood counts, serum chemistry panels, C-reactive protein measurements, coagulation testing and cytokine analyses were used for safety monitoring. Following IV administration of 3 mg/kg DAS, the estimated mean maximum plasma concentration was 54,709 ng/mL. Pharmacokinetic modeling suggested that DAS was eliminated with a half-life value of 8.1 h, equivalent to a clearance of 6.93 L/hr kg and a volume of distribution of 56 mL/kg. Plasma concentrations of the metabolites were measured rapidly (within 15-60 min for M1 and M2 respectively). Overall, the relative exposure to M1 and M2 suggest significant biotransformation of DAS occurred, but DAS was the most abundant circulating species. No adverse clinical reactions were noted following DAS administration and safety studies suggested DAS caused no inflammatory response or coagulation disturbance. Further clinical evaluation of DAS is warranted.


Asunto(s)
Aspirina/análogos & derivados , Compuestos de Bencidrilo/farmacocinética , Animales , Aspirina/farmacocinética , Cromatografía Liquida/veterinaria , Perros , Infusiones Intravenosas/veterinaria , Cinética
9.
Vet Med (Auckl) ; 12: 177-185, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34168973

RESUMEN

Two 8-week-old Finnish Lapphund dogs presented with pain on manipulation, abnormal long bone conformation, retrognathism, and stunted growth compared to their litter mates. Multiple long bone fractures were evident on radiographs. Clinical pathology showed an atypically normal serum alkaline phosphatase activity for dogs this age. Due to poor quality of life, the dogs were humanely euthanized and subjected to a complete necropsy. On necropsy, all bones were soft and easily broken. Histologic examination revealed that the secondary spongiosa was diminished with abnormal bony trabeculae embedded in abundant loose vascular stroma. No Haversian canals were observed and the cortices contained abundant woven bone separated by fibrovascular tissue consistent with the diagnosis of osteogenesis imperfecta (OI). Inbreeding of the sire and female offspring led to a suspicion of recessive inheritance and the particular genetic collagen disorder remains to be identified in this breed.

10.
Vet Pathol ; 58(5): 809-828, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33769136

RESUMEN

Tumor grading is a method to quantify the putative clinical aggressiveness of a neoplasm based on specific histological features. A good grading system should be simple, easy to use, reproducible, and accurately segregate tumors into those with low versus high risk. The aim of this review is to summarize the histological and, when available, cytological grading systems applied in veterinary pathology, providing information regarding their prognostic impact, reproducibility, usefulness, and shortcomings. Most of the grading schemes used in veterinary medicine are developed for common tumor entities. Grading systems exist for soft tissue sarcoma, osteosarcoma, multilobular tumor of bone, mast cell tumor, lymphoma, mammary carcinoma, pulmonary carcinoma, urothelial carcinoma, renal cell carcinoma, prostatic carcinoma, and central nervous system tumors. The prognostic relevance of many grading schemes has been demonstrated, but for some tumor types the usefulness of grading remains controversial. Furthermore, validation studies are available only for a minority of the grading systems. Contrasting data on the prognostic power of some grading systems, lack of detailed instructions in the materials and methods in some studies, and lack of data on reproducibility and validation studies are discussed for the relevant grading systems. Awareness of the limitations of grading is necessary for pathologists and oncologists to use these systems appropriately and to drive initiatives for their improvement.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias Renales , Neoplasias de la Vejiga Urinaria , Animales , Carcinoma de Células Transicionales/veterinaria , Neoplasias Renales/veterinaria , Clasificación del Tumor , Pronóstico , Reproducibilidad de los Resultados , Neoplasias de la Vejiga Urinaria/veterinaria
11.
J Dairy Sci ; 103(2): 1956-1968, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31864738

RESUMEN

Postpartum dairy cows experience a heightened inflammatory state coinciding with the time of greatest nutrient deficit. Nutrient availability is sensed on the cellular level by nutrient sensing kinases, such as the PI3K/AKT/mTOR (mTOR) pathway, a key orchestrator of immune cell activation and inflammatory balance. Our objective was to determine the responsiveness of this pathway to inflammatory stimulation with and without nutrient supplementation ex vivo. Blood samples were collected from Holstein cows (n = 14) at -42, -14, 7, 21, and 42 d relative to calving. Control samples and samples pretreated with a mixture of amino acids, glucose, and insulin (AAM) were stimulated with 100 ng/mL E. coli lipopolysaccharide (LPS; LPS, AAMLPS) or left unstimulated (control, AAM). After 1 h, ratios of mean fluorescence intensity for phosphorylated to total protein of AKT and mTORC1 substrates S6RP and 4EBP1 were analyzed in polymorphonuclear cells (PMN), and monocytes by flow cytometry. A separate aliquot was stimulated with LPS for 2 h and relative mRNA abundance of IL10, IL12A, IL12B, and TNFA in whole blood leukocytes from 10 cows was measured by reverse-transcription quantitative PCR. Repeated measures ANOVA was performed with fixed effects of time, treatment, and their interaction. Cells had different ratios of pathway proteins with PMN having the highest phosphorylation of AKT, S6RP, and 4EBP1. Stimulation with LPS consistently activated mTOR signaling in PMN regardless of nutrient supplementation except for postpartum 4EBP1, which increased in response to nutrients alone. In monocytes, AKT baseline phosphorylation was lower and activation could not be induced by either treatment, whereas activation of 4EBP1 responded to nutrient supplementation. Treatment with LPS increased phosphorylation of S6RP in both innate immune cell types. Nutrient supplementation increased baseline IL10 expression and decreased baseline as well as LPS-induced IL12B and TNFA expression. We conclude that the mTOR pathway in bovine innate immune cells can be differentially activated in response to inflammatory stimulation and nutrient supplementation in monocytes versus PMN. Effects of nutrient supplementation on cytokine mRNA abundance are likely specific to immune cell type.


Asunto(s)
Bovinos/fisiología , Suplementos Dietéticos/análisis , Inmunidad Innata , Inflamación/veterinaria , Lipopolisacáridos/administración & dosificación , Transducción de Señal/efectos de los fármacos , Aminoácidos/metabolismo , Animales , Bovinos/inmunología , Estudios de Cohortes , Citocinas/genética , Escherichia coli/química , Femenino , Inflamación/inducido químicamente , Monocitos/metabolismo , Neutrófilos/metabolismo , Nutrientes , Fosforilación , Periodo Posparto , Estudios Prospectivos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
12.
Vet Clin North Am Equine Pract ; 35(3): 433-455, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31672198

RESUMEN

Given the stoic nature of donkeys and their hybrids, it is important to consider the significance of diagnostic testing modalities that can provide objective health status information beyond the basic physical examination findings. However, clinical pathology assays are also fraught with significant limitations because the results for donkeys, mules, and hinnies can be difficult to interpret, and transference of data from the horse is not always applicable. This article presents considerations for sample collection, storage, analysis, and interpretation strategies for clinical pathology testing of donkeys and their hybrids based on the limited information available in the literature.


Asunto(s)
Equidae , Enfermedades de los Caballos/patología , Animales , Caballos , Patología Clínica
13.
J Biol Chem ; 294(43): 15623-15637, 2019 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-31434739

RESUMEN

Defects in the Fanconi anemia (FA) DNA damage-response pathway result in genomic instability, developmental defects, hematopoietic failure, cancer predisposition, and metabolic disorders. The endogenous sources of damage contributing to FA phenotypes and the links between FA and metabolic disease remain poorly understood. Here, using mice lacking the Fancd2 gene, encoding a central FA pathway component, we investigated whether the FA pathway protects against metabolic challenges. Fancd2-/- and wildtype (WT) mice were fed a standard diet (SD), a diet enriched in fat, cholesterol, and cholic acid (Paigen diet), or a diet enriched in lipid alone (high-fat diet (HFD)). Fancd2-/- mice developed hepatobiliary disease and exhibited decreased survival when fed a Paigen diet but not a HFD. Male Paigen diet-fed mice lacking Fancd2 had significant biliary hyperplasia, increased serum bile acid concentration, and increased hepatic pathology. In contrast, female mice were similarly impacted by Paigen diet feeding regardless of Fancd2 status. Upon Paigen diet challenge, male Fancd2-/- mice had altered expression of genes encoding hepatic bile acid transporters and cholesterol and fatty acid metabolism proteins, including Scp2/x, Abcg5/8, Abca1, Ldlr, Srebf1, and Scd-1 Untargeted lipidomic profiling in liver tissue revealed 132 lipid species, including sphingolipids, glycerophospholipids, and glycerolipids, that differed significantly in abundance depending on Fancd2 status in male mice. We conclude that the FA pathway has sex-specific impacts on hepatic lipid and bile acid metabolism, findings that expand the known functions of the FA pathway and may provide mechanistic insight into the metabolic disease predisposition in individuals with FA.


Asunto(s)
Bilis/metabolismo , Dieta , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/deficiencia , Metabolismo de los Lípidos , Hígado/metabolismo , Caracteres Sexuales , Animales , Colesterol/metabolismo , Daño del ADN , Enfermedades del Sistema Digestivo/metabolismo , Susceptibilidad a Enfermedades , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/metabolismo , Conducta Alimentaria , Femenino , Regulación de la Expresión Génica , Cinética , Metabolismo de los Lípidos/genética , Masculino , Ratones
14.
Nature ; 569(7757): 565-569, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31019307

RESUMEN

Atherosclerosis, which underlies life-threatening cardiovascular disorders such as myocardial infarction and stroke1, is initiated by passage of low-density lipoprotein (LDL) cholesterol into the artery wall and its engulfment by macrophages, which leads to foam cell formation and lesion development2,3. It is unclear how circulating LDL enters the artery wall to instigate atherosclerosis. Here we show in mice that scavenger receptor class B type 1 (SR-B1) in endothelial cells mediates the delivery of LDL into arteries and its accumulation by artery wall macrophages, thereby promoting atherosclerosis. LDL particles are colocalized with SR-B1 in endothelial cell intracellular vesicles in vivo, and transcytosis of LDL across endothelial monolayers requires its direct binding to SR-B1 and an eight-amino-acid cytoplasmic domain of the receptor that recruits the guanine nucleotide exchange factor dedicator of cytokinesis 4 (DOCK4)4. DOCK4 promotes internalization of SR-B1 and transport of LDL by coupling the binding of LDL to SR-B1 with activation of RAC1. The expression of SR-B1 and DOCK4 is increased in atherosclerosis-prone regions of the mouse aorta before lesion formation, and in human atherosclerotic arteries when compared with normal arteries. These findings challenge the long-held concept that atherogenesis involves passive movement of LDL across a compromised endothelial barrier. Interventions that inhibit the endothelial delivery of LDL into artery walls may represent a new therapeutic category in the battle against cardiovascular disease.


Asunto(s)
Arterias/metabolismo , Aterosclerosis/metabolismo , LDL-Colesterol/metabolismo , Células Endoteliales/metabolismo , Proteínas Activadoras de GTPasa/metabolismo , Receptores Depuradores de Clase B/metabolismo , Transcitosis , Animales , Aorta/citología , Aorta/metabolismo , Aorta/patología , Arterias/citología , Arterias/patología , Aterosclerosis/patología , Células Cultivadas , Femenino , Humanos , Macrófagos/metabolismo , Masculino , Ratones , Neuropéptidos/metabolismo , Proteína de Unión al GTP rac1/metabolismo
15.
BMC Vet Res ; 15(1): 475, 2019 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-31888626

RESUMEN

BACKGROUND: Immune-mediated hemolytic anemia (IMHA) is a common disease that affects all breeds of dogs and is associated with significant morbidity and mortality. Intravascular hemolysis of erythrocytes in IMHA is caused by complement activation and is often fatal. No current treatments target complement activation in canine IMHA. Human C1 esterase (C1-INH) reduces canine complement-mediated hemolysis in vitro, and a recent pharmacokinetic analysis of an FDA licensed formulation of C1-INH in dogs confirmed that a 50 IU/kg dose of C1-INH is safe to administer to dogs, and effectively inhibits canine complement mediated hemolysis ex-vivo. The C1INCH randomized controlled trial will evaluate the efficacy of this drug in dogs with intravascular hemolysis. METHODS: We will conduct a multicenter, placebo-controlled double-blind randomized clinical trial of C1-INH in dogs with intravascular hemolysis due to IMHA. We will randomize 18 dogs to receive three doses of intravenous C1-INH or saline in 24 h. Immunosuppressive and antithrombotic therapies will be standardized. Primary outcome measures will be changes in plasma free hemoglobin, serum concentrations of LDH, bilirubin, and haptoglobin. Using patient samples, we will evaluate complement activation in canine IMHA using a novel C5b-9 ELISA assay, flow cytometric detection of C3b on RBC, and by measurement of residual plasma complement activity. Secondary outcome measures will be survival to hospital discharge, duration of hospitalization, number and volume of red blood cell transfusions, and rescue therapy requirements. We will monitor dogs for adverse drug reactions. Sample size was estimated from pilot data on LDH and hemolysis index (HI) in dogs with IMHA. To detect 2-way differences between the upper and lower 50% of the LDH and HI values of equivalent size with 80% power at P < 0.05 will require 9 dogs in each arm. DISCUSSION: We anticipate that IV administration of C1-INH will significantly inhibit complement mediated hemolysis in dogs with intravascular IMHA, as determined by blood biomarker measurements (decreased plasma hemoglobin, LDH and bilirubin, increased haptoglobin). We expect this will translate into significant reductions in transfusion requirements and duration of hospitalization. TRIAL REGISTRATION: This trial has been prospectively registered with the AVMA registry (AAHSD005025).


Asunto(s)
Anemia Hemolítica Autoinmune/veterinaria , Proteína Inhibidora del Complemento C1/farmacología , Enfermedades de los Perros/tratamiento farmacológico , Anemia Hemolítica Autoinmune/tratamiento farmacológico , Animales , Perros , Femenino , Hemólisis/efectos de los fármacos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Vet Immunol Immunopathol ; 203: 66-72, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30243377

RESUMEN

Complement-mediated intravascular hemolysis occurs in canine immune-mediated hemolytic anemia (IMHA). Complement inhibitors such as recombinant C1 esterase inhibitor (rC1-INH) might prevent this process and alter the disease course. This study aimed to characterize the pharmacokinetics of a single 500 IU IV dose of rC1-INH in 8 healthy beagle dogs, evaluate the dogs for any adverse effects of drug administration, and determine whether rC1-INH administration induces anti-drug antibody formation. Serum rC1-INH concentrations were measured using a commercial functional ELISA at baseline and at 10, 20, 40, 60, 80, 100, 120, 240, 360, 480, 600, 720, 960, and 1440 min post drug administration. Complete blood counts were conducted at baseline, 720 and 1440 min. Western blot analysis, using rC1-INH as the target antigen was used to detect anti-drug antibodies in 14-day serum samples. No adverse clinical reactions were noted following rC1-INH administration. Pharmacokinetic modelling suggested that the peak C1-INH concentration achieved is 0.21 IU/mL and that C1-INH concentration is significantly greater than baseline for 100 min following injection. A robust antibody response was detected which suggests that rC1-INH should not be re-administered after an initial course. Clinical trials of rC1-INH in dogs with intravascular IMHA are now warranted.


Asunto(s)
Anticuerpos/inmunología , Proteína Inhibidora del Complemento C1/farmacocinética , Animales , Anticuerpos/sangre , Recuento de Células Sanguíneas/veterinaria , Western Blotting/veterinaria , Proteína Inhibidora del Complemento C1/análisis , Perros/inmunología , Humanos , Inyecciones Intravenosas/veterinaria , Masculino , Proteínas Recombinantes/sangre , Proteínas Recombinantes/farmacocinética
17.
Vet Surg ; 47(7): 951-957, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30180278

RESUMEN

OBJECTIVE: To determine the number of use/cleaning/resterilization cycles that can be safely applied to a vessel sealing device intended for single use (LigaSure). STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: LigaSure Small Jaw handsets (n = 6) and LigaSure Impact handsets (n = 6). METHODS: Handsets underwent simulated splenectomy/cleaning/resterilization cycles until failure, defined as leaking vascular seal or blade retraction failure. Functional testing included assessment of vascular seal integrity, handset activation/tissue release, and cutting blade wear/retraction. Vascular seal failure was defined as a leak occurring at <300 mm Hg. Cycles to failure were recorded. Sealed vessels were evaluated by histology at first handset use and failure. RESULTS: Vascular seals created with the Small Jaw handset failed at a mean (95% CI) of 17.2 cycles (9.6-24.8) and a minimum of 10 cycles. Vascular seals created with the Impact failed at a mean of 20 cycles (18.4-21.6) and a minimum of 17 cycles. The majority of seal failures (73%; 95% CI 39%-94%) immediate leaked during vessel filling. The rate of vascular seal failure increased after the initial failure. Failure was associated with histologic disparities in tissue apposition. CONCLUSION: Repeated use and resterilization resulted in failure of the vascular seal due to inadequate tissue apposition after a minimum of 10 cycles. CLINICAL SIGNIFICANCE: Surgeons reusing and resterilizing LigaSure handsets (ForceTriad platform) should consider discarding handsets after 9 cycles for the Small Jaw and after 16 cycles for the Impact. Handsets should be immediately discarded after any intraoperative identification of vascular seal failure.


Asunto(s)
Equipos Desechables/veterinaria , Equipo Reutilizado/veterinaria , Instrumentos Quirúrgicos/veterinaria , Animales , Diseño de Equipo , Ligadura/instrumentación , Ligadura/veterinaria , Esterilización
18.
J Vet Emerg Crit Care (San Antonio) ; 28(3): 252-260, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29631333

RESUMEN

OBJECTIVE: To compare lipid emulsion-induced hemolysis in blood from dogs with inflammatory leukograms to blood from healthy dogs, and determine the impact of a prototypical soy-based phospholipid emulsion on coagulation in whole blood from healthy dogs. DESIGN: Ex vivo study using EDTA and citrated whole blood from healthy dogs and EDTA anticoagulated whole blood from dogs with inflammatory leukograms. SETTING: University research laboratory. ANIMALS: Healthy dogs (total of 16, 9 for hemolysis assays and 6 for thromboelastography) included student- and staff-owned animals. Blood samples from dogs with inflammatory leukograms (8) were obtained from the clinical pathology laboratory after the complete blood count was performed as part of patient care. For the purposes of this study, an inflammatory leukogram was defined as a neutrophilia with a left-shift (minimum of 3% band neutrophils) and evidence of toxic change. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Hemolysis was measured via spectrophotometric quantification of released hemoglobin and expressed as a percent of a water-lysed control. The soy emulsion caused hemolysis in blood from healthy dogs, ranging from 3.6% to 16.4% as the dose increased, and 4.1% to 25.0% in blood from dogs with inflammatory leukograms. Hemolysis between these patient groups was significantly different at the highest dose. Coagulation was assessed by native thromboelastography. Treatment of whole blood with the lipid emulsion caused a significant decrease in the time to clot formation (R) and a shorter time to reach a clot amplitude of 20 mm (K). CONCLUSIONS: Soy-based lipid emulsions cause hemolysis that is more severe in blood from dogs with inflammatory leukograms and accelerate clot formation in canine blood. The in vivo significance of these findings is not clear at this time, but warrants additional investigation given the use of these emulsions in clinical practice.


Asunto(s)
Enfermedades de los Perros/sangre , Emulsiones Grasas Intravenosas/farmacología , Glycine max , Inflamación/veterinaria , Agregación Plaquetaria/efectos de los fármacos , Animales , Pruebas de Coagulación Sanguínea/veterinaria , Estudios de Casos y Controles , Perros , Emulsiones Grasas Intravenosas/administración & dosificación , Femenino , Inflamación/tratamiento farmacológico , Masculino , Tromboelastografía/veterinaria
19.
Front Vet Sci ; 5: 340, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30687727

RESUMEN

Altered lipid metabolism is a well-documented hallmark of neoplastic transformation and impacts disease progression. Two major lipoprotein receptors, the low-density lipoprotein receptor (LDL-R) and scavenger receptor class B, type 1 (SR-BI) are overexpressed in a number of cancer types in people. These receptors serve to deliver cholesterol to the tumor cells and have been used to target drug therapies. In this study, we performed a retrospective analysis of LDL-R and SR-B1 expression in canine lymphoma using archived formalin-fixed tissue samples. Cases were immunophenotyped and classified according to World Health Organization (WHO) standards prior to immunostaining for the LDL_R and SR-B1. A total of 45 cases were evaluated; 21 high grade B (HGB), 11 low grade B (LGB), 7 high grade T (HGT), and 6 low grade T (LGT) lymphomas. One sided Wilcoxon rank sum tests were used to compare staining intensity between neoplastic and hyperplastic lymphoid tissue. The relationships between histological score and tumor grade and score and stage at presentation were assessed using non-parametric Kruskal-Wallis tests. Neoplastic lymphoid tissue expressed higher levels of both receptors compared to reactive lymph nodes. Median LDL-R score was 85.0 (interquartile range = 101.7), Median SR-B1 score was 209.0 (interquartile range 105.2). No relationship between LDL-R or SR-B1 staining score and tumor grade or phenotype was found. Serum cholesterol concentration was compared between dogs with high and low grade tumors using a two sample T-test, and correlations between cholesterol concentration and histological score, and between the score for the two receptors were determined using a Spearman correlation. The high expression level of these lipoprotein receptors on most of the tumors could underlie the lack of relationship between score and tumor grade. The overexpression of LDL-R and SR-B1 in canine lymphoma holds therapeutic potential particularly in dogs that overexpress one or both of these receptors, and this warrants further investigation.

20.
J Zoo Wildl Med ; 48(2): 319-327, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28749274

RESUMEN

Thei-STAT® portable clinical analyzer (PCA) provides patient-side results for hematologic, biochemical, and blood gas values when immediate results are desired. This analyzer is commonly used in nondomestic animals; however, validation of this method in comparison with traditional benchtop methods should be performed for each species. In this study, the i-STAT PCA was compared with the Radiometer ABL 800 Flex benchtop analyzer using 24 heparinized whole blood samples obtained from healthy E. maximus . In addition, the effect of sample storage was evaluated on the i-STAT PCA. Analytes evaluated were hydrogen ion concentration (pH), glucose, potassium (K+), sodium (Na+), bicarbonate (HCO3-), total carbon dioxide (TCO2), partial pressure of carbon dioxide (PCO2), and ionized calcium (iCa2+). Statistical analysis using correlation coefficients, Passing-Bablok regression analysis, and Bland-Altman plots found good agreement between results from samples run immediately after phlebotomy and 4 hr postsampling on the i-STAT PCA with the exception of K+, which is known to change with sample storage. Comparison of the results from the two analyzers at 4 hr postsampling found very strong or strong correlation in all values except K+, with statistically significant bias in all values except glucose and PCO2. Despite bias, mean differences assessed via Bland-Altman plots were clinically acceptable for all analytes excluding K+. Within the reference range for iCa2+, the iCa2+ values obtained by the i-STAT PCA and Radiometer ABL 800 Flex were close in value, however in light of the constant and proportionate biases detected, overestimation at higher values and underestimation at lower values of iCa2+ by the i-STAT PCA would be of potential concern. This study supports the use of the i-STAT PCA for the evaluation of these analytes, with the exception of K+, in the Asian elephant.


Asunto(s)
Análisis Químico de la Sangre/veterinaria , Calcio/sangre , Elefantes/sangre , Animales , Análisis Químico de la Sangre/instrumentación , Femenino , Masculino , Sistemas de Atención de Punto , Radiometría/instrumentación , Radiometría/veterinaria , Análisis de Regresión
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