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1.
Intern Med J ; 52(8): 1434-1436, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35973960

RESUMO

We have analysed insulin antibodies in 149 adults with type 1 diabetes and 2859 people without diabetes. We have determined that insulin antibody levels are higher in adults with, versus without, diabetes and that the levels are falling, and more patients are becoming antibody-negative post islet cell transplantation.


Assuntos
Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Adulto , Austrália/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/cirurgia , Humanos , Terapia de Imunossupressão , Insulina , Anticorpos Anti-Insulina
2.
J Vet Pharmacol Ther ; 44(3): 349-358, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33305843

RESUMO

Capsaicinoids deter horses from chewing on bandages and are applied topically to provide analgesia to musculoskeletal injuries. They are banned during competition due to their nerve blocking properties. The pharmacokinetics of oral (PO) and direct gastric administration via nasogastric tube (NG), or topical (TOP) administration of two capsaicinoid-containing products were investigated, and the withdrawal times required prior to competition were estimated. Capsaicin (CAP) and dihydrocapsaicin (DCAP) were quantified in plasma, and both compounds were best described by a delayed absorption two compartment elimination model following PO administration and by a first order absorption one compartment elimination model following TOP administration. Capsaicin and DCAP could not be quantified in most samples following NG administration. Following PO administration, the time to maximum plasma concentration (Tmax ) for CAP and DCAP was 0.25 (0.08-0.50) hr. Following TOP application, the Tmax for CAP and DCAP was 4 (2-6) and 5 (3-12) hr, respectively. By 8 hr post-PO administration and 36 hr post-TOP application, CAP and DCAP were below the lower limit of quantification. Capsaicin and DCAP were not detected in urine samples. Withdrawal times were predicted using the 99.99% credibility interval limits of the pharmacokinetic parameters calculated with Bayesian estimation.


Assuntos
Teorema de Bayes , Administração Oral , Administração Tópica , Animais , Cavalos
3.
Am J Physiol Endocrinol Metab ; 318(3): E392-E404, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31910030

RESUMO

In adipose, insulin functions to suppress intracellular lipolysis and secretion of nonesterified fatty acid (NEFA) into plasma. We applied glucose and NEFA minimal models (MM) following a frequently sampled intravenous glucose tolerance test (FSIVGTT) to assess glucose-specific and NEFA-specific insulin resistance. We used total NEFA and individual fatty acids in the NEFA MM, comparing the model parameters in metabolic syndrome (MetSyn) subjects (n = 52) with optimally healthy controls (OptHC; n = 14). Results are reported as mean difference (95% confidence interval). Using the glucose MM, MetSyn subjects had lower [-73% (-82, -57)] sensitivity to insulin (Si) and higher [138% (44, 293)] acute insulin response to glucose (AIRg). Using the NEFA MM, MetSyn subjects had lower [-24% (-35, -13)] percent suppression, higher [32% (15, 52)] threshold glucose (gs), and a higher [81% (12, 192)] affinity constant altering NEFA secretion (ϕ). Comparing fatty acids, percent suppression was lower in myristic acid (MA) than in all other fatty acids, and the stearic acid (SA) response was so unique that it did not fit the NEFA MM. MA and SA percent of total were increased at 50 min after glucose injection, whereas oleic acid (OA) and palmitic acid (PA) were decreased (P < 0.05). We conclude that the NEFA MM, as well as the response of individual NEFA fatty acids after a FSIVGTT, differ between OptHC and MetSyn subjects and that the NEFA MM parameters differ between individual fatty acids.


Assuntos
Ácidos Graxos não Esterificados/metabolismo , Hiperglicemia/metabolismo , Hipoglicemia/metabolismo , Resistência à Insulina , Adulto , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Método Duplo-Cego , Feminino , Glucose/farmacologia , Teste de Tolerância a Glucose , Humanos , Secreção de Insulina/efeitos dos fármacos , Lipídeos/sangue , Masculino , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade
4.
J Vet Pharmacol Ther ; 43(6): 557-564, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32424949

RESUMO

Intravenous (i.v.) bolus administration of xylazine (XYL) (0.5 mg/kg) immediately followed by a continuous rate infusion (CRI) of 1 mg kg-1  hr-1 for 2, 4, and 6 hr produced immediate sedation, which lasted throughout the duration of the CRI. Heart rate decreased and blood pressure increased significantly (p > .05) in all horses during the first 15 min of infusion, both returned to and then remained at baseline during the duration of the infusion. Compartmental models were used to investigate the pharmacokinetics of XYL administration. Plasma concentration-time curves following bolus and CRI were best described by a one-compartment model. No differences were found between pharmacokinetic estimates of the CRIs for the fractional elimination rate constant (Ke ), half-life (t1/2e ), volume of distribution (Vd ), and clearance (Cl). Median and range were 0.42 (0.15-0.97)/hr, 1.68 (0.87-4.52) hr, 5.85 (2.10-19.34) L/kg, and 28.7 (19.6-39.5) ml min-1  kg-1 , respectively. Significant differences were seen for area under the curve ( AUC 0 ∞ ) (p < .0002) and maximum concentration (Cmax ) (p < .04). This indicates that with increasing duration of infusion, XYL may not accumulate in a clinically relevant way and hence no adjustments are required in a longer XYL CRI to maintain a constant level of sedation and a rapid recovery.


Assuntos
Cavalos/metabolismo , Hipnóticos e Sedativos/farmacocinética , Xilazina/farmacocinética , Animais , Área Sob a Curva , Estudos Cross-Over , Esquema de Medicação , Feminino , Meia-Vida , Cavalos/sangue , Hipnóticos e Sedativos/sangue , Injeções Intravenosas , Masculino , Xilazina/sangue
5.
Hum Reprod ; 34(2): 335-344, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30576500

RESUMO

STUDY QUESTION: Are non-esterified fatty acid (NEFA) kinetics altered in women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Women with PCOS, particularly obese subjects, have dysregulated plasma NEFA kinetics in response to changes in plasma insulin and glucose levels, which are associated with insulin resistance (IR) independently of the fasting plasma NEFA levels. WHAT IS KNOWN ALREADY: Elevated plasma NEFA levels are associated with IR in many disorders, although the homeostasis of NEFA kinetics and its relationship to IR in women with PCOS is unknown. STUDY DESIGN, SIZE, DURATION: We prospectively compared insulin sensitivity and NEFA kinetics in 29 PCOS and 29 healthy controls women matched for BMI. PARTICIPANTS/MATERIALS, SETTING, METHODS: This study was conducted in a tertiary institution. Plasma NEFA, glucose and insulin levels were assessed during a modified frequently sampled intravenous glucose tolerance test (mFSIVGTT). Minimal models were used to assess insulin sensitivity (Si) and NEFA kinetics (i.e. model-derived initial plasma NEFA level [NEFA0], phi constant [Φ], reflecting glucose-mediated inhibition of lipolysis and measures of maximum rate of lipolysis [SFFA] and NEFA uptake from plasma [KFFA]). MAIN RESULTS AND THE ROLE OF CHANCE: The study provides new evidence that women with PCOS have defective NEFA kinetics characterized by: (i) lower basal plasma NEFA levels, measured directly and modeled (NEFA0), and (ii) a greater glucose-mediated inhibition of lipolysis in the remote or interstitial space (reflected by a lower affinity constant [Φ]). There were no differences, however, in the maximal rates of adipose tissue lipolysis (SFFA) and the rate at which NEFA leaves the plasma pool (KFFA). The differences observed in NEFA kinetics were exacerbated, and almost exclusively observed, in the obese PCOS subjects. LIMITATIONS, REASONS FOR CAUTION: Our study did not study NEFA subtypes. It was also cross-sectional and based on women affected by PCOS as defined by the 1990 National Institutes of Health (NIH) criteria (i.e. Phenotypes A and B) and identified in the clinical setting. Consequently, extrapolation of the present data to other phenotypes of PCOS should be made with caution. Furthermore, our data is exploratory and therefore requires validation with a larger sample size. WIDER IMPLICATIONS OF THE FINDINGS: Dysfunction in NEFA kinetics may be a marker of metabolic dysfunction in nondiabetic obese women with PCOS and may be more important than simply assessing circulating NEFA levels at a single point in time for understanding the mechanism(s) underlying the IR of PCOS. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by NIH grants R01-DK073632 and R01-HD29364 to R.A.; a Career Development Award from MD Medical Group, Moscow, RF, to D.L. and Augusta University funds to Y.-H.C. RA serves as consultant to Ansh Labs, Medtronics, Spruce Biosciences and Latitude Capital. U.E., Z.A., D.L., R.M., Y.-H.C., R.C.B. and Y.D.I.C. have no competing interests to declare. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Ácidos Graxos não Esterificados/metabolismo , Resistência à Insulina , Obesidade/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adolescente , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , Estudos Transversais , Ácidos Graxos não Esterificados/sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Lipólise , Obesidade/sangue , Obesidade/complicações , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/complicações , Estudos Prospectivos , Adulto Jovem
6.
Diabetes Obes Metab ; 21(8): 2012-2016, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31050161

RESUMO

Elevated levels of non-esterified fatty acids (NEFA) play a role in insulin resistance, impaired beta-cell function and they are a denominator of the abnormal atherogenic lipid profile that characterizes obese patients with type 2 diabetes (T2DM). We hypothesized that the GLP-1 receptor agonist liraglutide, in combination with metformin, would reduce lipolysis. In a randomized, double-blind, placebo-controlled, cross-over trial, 41 T2DM patients with coronary artery disease were randomized and treated with liraglutide-metformin vs placebo-metformin during 12- + 12-week periods with a wash-out period of at least 2 weeks before and between the intervention periods. NEFA kinetics were estimated using the Boston Minimal Model of NEFA metabolism, with plasma NEFA and glucose levels measured during a standard 180-minute frequently sampled intravenous glucose tolerance test. Liraglutide-metformin reduced estimates of lipolysis. Furthermore, placebo-metformin increased estimates of lipid oxidation, while treatment with liraglutide eliminated this effect. We conclude that liraglutide exerts a clinically relevant reduction in estimates of lipolysis and lipid oxidation which is explained, in part, by improved insulin secretion, as revealed by an intravenous glucose tolerance test.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Lipólise/efeitos dos fármacos , Liraglutida/farmacologia , Obesidade/fisiopatologia , Oxirredução/efeitos dos fármacos , Idoso , Glicemia/efeitos dos fármacos , Doença da Artéria Coronariana/complicações , Estudos Cross-Over , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Método Duplo-Cego , Quimioterapia Combinada , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Metformina/farmacologia , Pessoa de Meia-Idade , Obesidade/complicações , Resultado do Tratamento
7.
J Vet Pharmacol Ther ; 42(5): 541-547, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31325161

RESUMO

Equine metabolic syndrome (EMS) is prevalent in the equine population, and somatostatin analogs might be useful for diagnosis and/or treatment of EMS in horses. The purpose of this study was to evaluate the glucose and insulin responses to subcutaneous and intravenous administration of somatostatin. Six healthy research horses were included in this prospective study. An initial pilot study was performed to assess several different doses (10-22 µg/kg [4.5-10 µg/lb]) in two horses, then a final dosage of 22 µg/kg (10 µg/lb) was administered to six horses IV and SQ in a two-period randomized cross-over study performed over a 3-month study period. Blood samples were collected for measurement of plasma insulin and glucose concentrations during a 24-hr study period. Both IV and SQ somatostatin resulted in decreased insulin and increased glucose concentrations. SQ somatostatin resulted in a longer clinical effect, with return to baseline insulin occurring at 1.5 hr postadministration, versus 45 min for IV. Both IV and SQ administration of somatostatin to normal horses resulted in decreased insulin and increased glucose concentrations, likely due to suppression of insulin secretion by somatostatin. A more prolonged effect was seen following SQ administration as compared to IV administration, and no adverse effects were noted at varying doses. This study provides additional information regarding the effect of somatostatin administration on insulin and glucose concentrations in clinically healthy horses.


Assuntos
Glicemia , Hormônios/farmacologia , Cavalos/sangue , Insulina/sangue , Somatostatina/farmacologia , Administração Intravenosa , Animais , Estudos Cross-Over , Relação Dose-Resposta a Droga , Hormônios/administração & dosagem , Injeções Subcutâneas , Somatostatina/administração & dosagem
8.
Vet Dermatol ; 30(3): 255-e78, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30828914

RESUMO

BACKGROUND: The long-term effects of allergen specific immunotherapy (ASIT) on concentrations of circulating immunoglobulin E (IgE) and immunoglobulin G (IgG) in horses have not been reported. OBJECTIVES: To document changes in clinical severity of horses with atopic dermatitis (AD) and to monitor allergen-specific IgE and IgG concentrations during a two-year course of ASIT. ANIMALS: Nineteen client-owned horses with a conditional diagnosis of AD. METHODS AND MATERIALS: Three ASIT groups were randomly assigned based upon results obtained by either intradermal testing (IDT) for regional allergens (n = 7); enzyme-linked immunosorbent assay (ELISA) for specific IgE (n = 6); or a composite of results from both tests (n = 6). Serum concentrations of IgE and IgG specific for allergens included in ASIT were measured at time zero and at four-month intervals. A visual analog scale (VAS) was used to record severity of clinical signs at times zero, 12 and 24 months. RESULTS: Positive correlations were documented between IgE and both immediate and delayed IDT results (P < 0.00001), and between immediate IDT and IgG results (P = 0.003). Specific IgE in sera decreased significantly (P < 0.05) for allergens that were included in ASIT, whereas IgG increased. Across all horses, the mean VAS score decreased by 1.2 units [95% CI: 1.28, 1.14; (P < 0.0001)] during each 12-month period of ASIT therapy. Improvement in clinical signs was noted in 76.5% of the horses following 12 months of ASIT and in 82% after 24 months on ASIT. CONCLUSIONS AND CLINICAL IMPORTANCE: In this pilot study, ASIT in horses with AD provided significant clinical benefit associated with a concomitant reduction of allergen-specific IgE and elevation of IgG.


Assuntos
Dermatite Atópica/veterinária , Dessensibilização Imunológica/veterinária , Doenças dos Cavalos/imunologia , Imunoglobulina E/imunologia , Alérgenos/imunologia , Animais , Dermatite Atópica/terapia , Ensaio de Imunoadsorção Enzimática , Doenças dos Cavalos/terapia , Cavalos/imunologia , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Testes Intradérmicos/veterinária , Estudos Longitudinais , Propriedade , Projetos Piloto
9.
J Vet Pharmacol Ther ; 41(6): 825-837, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30028024

RESUMO

Intravenous (iv), subcutaneous (sq), and topical (tp) lidocaine was administered to six horses in a cross-over, randomized design study. Samples were collected for up to 72 hr. Compartmental models were used to investigate the pharmacokinetics of (LD) and its metabolites 3-hydroxylidocaine (3-OH), 4-hydroxylidocaine (4-OH), and monoethylglycinexylidide (MEGX). Metabolites 3-OH and 4-OH were present in conjugated forms, whereas LD and metabolite MEXG were present primarily in the un-conjugated form. Plasma concentrations of LD after iv administration (100 mg) were described by three-compartment model with an additional three compartments to describe the elimination of metabolites. Median (range) elimination micro-constants (Ke ) for LD, 3-OH, 4-OH, and MEXG were 4.12 (2.62-6.23), 1.25 (1.10-2.15), 1.79 (1.22-2.39), and 1.69 (1.03-1.99)/hr, respectively. Median (range) values of alpha (t½α ), beta (t½ß ), and gamma (t½Î³ ) half-lives were 0.08 (0.07-0.13), 0.57 (0.15-1.25), and 4.11 (0.52-7.36) hr. Plasma concentrations of LD after sq (200 mg) administration were described by absorption and two-compartment elimination model. The median (range) of the LD absorption half-life (t½ab ) was 0.47 (0.29-0.61) hr. The Ke for LD, 3-OH, 4-OH, and MEXG was 3.91 (1.48-9.25), 1.00 (0.78-1.08), 1.76 (0.96-2.11), and 1.13 (0.69-1.33)/hr. The median (range) of t½α and t½ß was 0.15 (0.06-0.27) and 3.04 (2.53-6.39) hr. Plasma concentrations of LD after tp (400 mg) application were described by one-compartment model with a t½ab of 8.49 (5.16-11.80) hr. The Ke for LD, 3-OH, and MEXG was 0.24 (0.10-0.81), 0.41 (0.08-0.93), and 0.38 (0.26-1.14)/hr.


Assuntos
Anestésicos Locais/farmacocinética , Cavalos/metabolismo , Lidocaína/análogos & derivados , Lidocaína/farmacocinética , Anestésicos Locais/administração & dosagem , Animais , Área Sob a Curva , Estudos Cross-Over , Vias de Administração de Medicamentos , Feminino , Meia-Vida , Cavalos/sangue , Lidocaína/administração & dosagem , Lidocaína/farmacologia , Masculino , Distribuição Aleatória
10.
Vet Surg ; 46(5): 700-704, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28462516

RESUMO

OBJECTIVE: To determine the degree and ease of arytenoid abduction achieved with abaxial placement of a FASTak II suture anchor compared to 2 suture patterns with different directions of insertion-caudomedial to craniolateral and medial to lateral. STUDY DESIGN: Ex vivo experimental. STUDY POPULATION: Cadaveric larynges from 10 Standardbred racehorses. METHODS: Each larynx was sequentially instrumented with all 3 arytenoid suture attachment in random order: (1) abaxial placement of a FASTak II suture, (2) caudomedial to craniolateral suture, and (3) medial to lateral suture placement. Each construct was abducted at 5N increments from 0 to 25N and the left to right quotient angle ratio (LRQ) measured from digital pictures acquired at each sequential increment. RESULTS: Arytenoid abduction (higher LRQ) was greater with FASTak II construct than either of the suture patterns. The largest difference occurred at 5N. Approximately 50% less force was required to achieve an LRQ of 1.0 with the FASTak II anchor compared to the suture patterns. No difference was detected between the 2 suture constructs throughout the study. CONCLUSION: Use of the FASTak II suture anchor improved arytenoid abduction compared to 2 suture patterns and minimized the suture loads required to achieve maximum arytenoid abduction. CLINICAL RELEVANCE: Use of the FASTak II anchor may decrease the suture load required to achieve arytenoid abduction in clinical cases. This may reduce the load placed on the laryngoplasty, thereby, minimizing postoperative loss of abduction.


Assuntos
Cartilagem Aritenoide/cirurgia , Laringoplastia/veterinária , Próteses e Implantes/veterinária , Técnicas de Sutura/veterinária , Animais , Cadáver , Cavalos , Laringoplastia/métodos , Laringe/cirurgia , Âncoras de Sutura , Suturas
11.
Pain Med ; 15(5): 791-806, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24517173

RESUMO

OBJECTIVE: To develop a framework for integrating pharmacogenetics with clinical pharmacokinetics for personalized oxycodone dosing based on a patient's CYP2D6 phenotype. DESIGN: Randomized, crossover, double-blind, placebo-controlled. Subjects were genotyped as CYP2D6 ultra-rapid metabolizer, extensive metabolizer, or poor metabolizer phenotypes. Five subjects from each phenotype were randomly selected for inclusion in our study. SETTING: Studies were performed in silico. SUBJECTS: The subjects were male, age 26 years, height 181.2 cm, and weight 76.3 kg. They were healthy without comorbidities, and their medical examinations were normal. METHODS: The trajectories of phenotype-specific plasma oxycodone concentration-time profiles were analyzed using weighted nonlinear least-squares regression with WinSAAM software. A global two-stage population-based model data analysis procedure was used to analyze the studies. Clinical pharmacokinetics were calculated using the R package cpk, eliminating the need to perform hand-calculations. RESULTS: Our study shows how clinicians can reduce risk and increase effectiveness for oxycodone dosing by (1) determining the patient's likely metabolic response through testing a patient's CYP2D6 phenotype, and (2) calculating clinical pharmacokinetics specific to the patient's CYP2D6 phenotype to design a personalized oxycodone dosing regimen. CONCLUSIONS: Personalized oxycodone dosing is a new tool for a clinician treating chronic pain patients requiring oxycodone. By expressing a patient's CYP2D6 phenotype pharmacokinetically, a clinician (at least theoretically) can improve the safety and efficacy of oxycodone and decrease the risk for iatrogenically induced overdose or death. Pharmacokinomics provides a general framework for the integration of pharmacogenetics with clinical pharmacokinetics into clinical practice for gene-based prescribing.


Assuntos
Analgésicos Opioides/farmacocinética , Dor Crônica/tratamento farmacológico , Modelos Biológicos , Oxicodona/farmacocinética , Farmacogenética/métodos , Medicina de Precisão/métodos , Adulto , Algoritmos , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Dor Crônica/genética , Estudos Cross-Over , Citocromo P-450 CYP2D6/genética , Método Duplo-Cego , Genótipo , Humanos , Masculino , Dinâmica não Linear , Oxicodona/administração & dosagem , Oxicodona/efeitos adversos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/genética , Fenótipo , Risco
12.
Vet Dermatol ; 24(5): 525-e124, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23992283

RESUMO

BACKGROUND: Meticillin-resistant Staphylococcus aureus (MRSA) strain USA 500 predominately colonizes horses and people working with them. Previous studies demonstrate that some Staphylococcus species exhibit higher affinity for corneocytes of specific mammalian species. HYPOTHESIS/OBJECTIVES: The objective was to determine the relative affinities of various MRSA strains, meticillin-susceptible S. aureus (MSSA) strains and a meticillin-susceptible Staphylococcus pseudintermedius (MSSP) for equine corneocytes. We hypothesized that MRSA strain USA 500 would exhibit greater adhesion than other staphylococcal strains tested. METHODS: Epidemic MRSA strains (USA 100, USA 300, USA 500 and USA 800), two MSSA control strains and an MSSP field strain were tested on corneocytes from 15 client-owned horses. Isolates were incubated with corneocytes in conditions (bacterial concentration of 10(8) colony-forming units/mL for 45 min) recently shown to maximize adherence of S. aureus without competitive interference. A validated image-analysis system was used to quantify the cell surface density of bacterial adhesion. RESULTS: The MSSP strain adhered with significantly higher affinity (P < 0.0015) to corneocytes than did MSSA strains. All MRSA strains other than USA 500 had significantly higher affinity than MSSA strains (P range <0.03 to <0.0015). There were no statistical differences in adhesion between strain USA 500 and the other MRSA strains tested. CONCLUSIONS AND CLINICAL IMPORTANCE: Meticillin-resistant S. aureus strain USA 500 did not adhere more robustly than other strains of Staphylococcus; therefore, its affinity to colonize horses may not be solely attributed to corneocyte adhesion. Additional studies are required to explain the epidemiological role of this strain as the predominant cause of colonization and infections of horses in North America.


Assuntos
Aderência Bacteriana/fisiologia , Córnea/citologia , Cavalos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Animais , Células Cultivadas , Feminino , Masculino , Resistência a Meticilina , Especificidade da Espécie
13.
Vet Dermatol ; 23(1): 57-60, e13, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21992593

RESUMO

Meticillin-resistant Staphylococcus aureus (MRSA) causes serious skin and soft-tissue infections of humans and animals. Multiple strains of MRSA have been characterized, and one in particular, designated as strain USA 500, causes infections predominantly of horses and the people who work with them. The purpose of this study was to optimize an assay which could subsequently be used to compare the relative avidity of different S. aureus strains for equine corneocytes. Corneocytes were collected from the perineal skin of 10 healthy horses onto adhesive discs. The discs were then incubated at 37°C with an S. aureus field strain at each of three concentrations [10(7), 10(8) and 10(9) colony forming units (CFU)/mL] and for each of three incubation periods (45, 90 and 180 min). After standardized rinsing and staining procedures, discs were examined at ×1,000 magnification and areas containing confluent corneocytes photographed. The percentage of surface area occupied by adherent bacteria was analysed using image processing and analysis software. Significant colour space image processing was required to distinguish bacteria from the ubiquitous melanin granules present within equine corneocytes. Objective and subjective methods were used to determine optimal conditions for specific adherence without introducing confounding factors. A bacterial concentration of 10(8) CFU/mL incubated with corneocytes for 45 min produced maximal bacterial adhesion with the least amount of interbacterial clumping. Future studies should utilize these conditions for optimal assay performance.


Assuntos
Aderência Bacteriana , Bioensaio/veterinária , Cavalos/microbiologia , Pele/citologia , Staphylococcus aureus/fisiologia , Animais , Feminino , Masculino
14.
Vet Surg ; 41(8): 918-23, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23198920

RESUMO

OBJECTIVE: Mechanical evaluation of a novel alternate laryngoplasty system (ALPS). STUDY DESIGN: Experimental. ANIMAL POPULATION: Cadaveric horse larynges (n = 10). METHODS: Arytenoid and cricoid cartilages were embedded for testing. A novel laryngoplasty system consisting of a metallic anchor, 2 stands of #2 suture material, and a metallic button were evaluated. A traditional laryngoplasty using a single strand of #5 Ethibond was evaluated in parallel. Constructs were evaluated in cyclic testing oscillating from 30 to 50 N for 3600 cycles. Constructs subsequently underwent a single cycle to failure. Distraction during cyclic testing was recorded. Load at failure and stiffness were calculated from single-cycle failure testing. RESULTS: There was no difference in mean arytenoid single-cycle load-to-failure for the Ethibond (206.9 ± 13.1 N) constructs compared with ALPS (220.6 ±17.1 N) constructs (P = .486). In the cricoid under single-cycle testing, the ALPS (236.0 ± 23.4 N) constructs were significantly stronger than the Ethibond (161.5 ± 12.2 N) constructs (P = .013). The combined distraction was significantly greater for Ethibond (6.29 ± 1.24 mm) constructs compared to the ALPS (3.43 ± 0.28 mm) constructs (P = .033). CONCLUSIONS: The ALPS construct was stiffer and at least as strong as the traditional laryngoplasty construct in single cycle failure in both the arytenoid and cricoid cartilages. Combined distraction was significantly reduced using the ALPS compared to the traditional laryngoplasty in vitro under cyclic testing.


Assuntos
Cavalos , Doenças da Laringe/veterinária , Laringoplastia/veterinária , Animais , Cartilagem Aritenoide/cirurgia , Fenômenos Biomecânicos , Cadáver , Cartilagem Cricoide/cirurgia , Doenças dos Cavalos/cirurgia , Doenças da Laringe/cirurgia , Laringoplastia/métodos , Suturas/veterinária
15.
Vet Surg ; 41(3): 399-403, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22103338

RESUMO

OBJECTIVE: To determine the success of medical management of suspected displacement of the ascending (large) colon in horses. STUDY DESIGN: Retrospective case series. ANIMALS: Horses (n = 127) with suspected large colon displacement. METHODS: Medical records (January 1998-September 2008) of horses admitted for colic were reviewed. Suspected large colon displacement was diagnosed from clinical examination and in some cases, subsequent surgical examination. Medically managed horses were exercised and administered intravenous fluids and analgesia. Horses with suspected left dorsal displacement (LDD) of the large colon were also administered phenylephrine. RESULTS: Medical management had a high success rate for treatment of suspected right dorsal displacement (RDD) (64%) and LDD (76%) of the large colon; 4 horses died (1) or were euthanatized (3) and 36 horses had surgery. Of 127 horses treated medically or surgically for a colon displacement, 94% survived to hospital discharge. CONCLUSIONS: Horses with suspected RDD or LDD of the large colon may respond to medical management including exercise.


Assuntos
Doenças do Colo/veterinária , Doenças dos Cavalos/cirurgia , Animais , Colo Ascendente/cirurgia , Doenças do Colo/cirurgia , Cavalos , Estudos Retrospectivos , Resultado do Tratamento
17.
J Am Vet Med Assoc ; 238(10): 1305-15, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21568777

RESUMO

OBJECTIVE: To compare endogenous ACTH and α-melanocyte-stimulating hormone (α-MSH) concentrations after administration of thyrotropin-releasing hormone (TRH) and to compare ACTH concentrations after TRH administration with those following domperidone administration in healthy horses and horses with pituitary pars intermedia dysfunction (PPID). DESIGN: Prospective case series. ANIMALS: 69 clinically normal horses and 47 horses with or suspected to have PPID. PROCEDURES: ACTH concentrations were measured during 108 TRH stimulation tests in 88 horses, and α-MSH concentrations were measured during 56 TRH stimulation tests in 50 horses. In 28 of these horses, ACTH concentrations after domperidone administration were measured and test results were compared. The pituitary gland was histologically examined in all horses that were euthanatized. RESULTS: ACTH and α-MSH concentrations increased in all horses after TRH administration, with a greater and more prolonged increase in horses with PPID. Percentage increase was significantly greater for α-MSH concentration than for ACTH concentration. The change in ACTH concentration after domperidone administration was less consistent in differentiating clinically normal horses from those with PPID than was the response to TRH. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ACTH concentration in response to TRH administration was useful for the diagnosis of PPID in horses and appeared more accurate than response to domperidone administration. Use of an α-MSH concentration ≥ 30 or 50 pmol/L did not appear superior to use of an ACTH concentration ≥ 36 pg/mL for the diagnosis of PPID, either before or 30 minutes after TRH administration.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Domperidona/farmacologia , Doenças dos Cavalos/sangue , Doenças da Hipófise/veterinária , Hormônio Liberador de Tireotropina/farmacologia , alfa-MSH/sangue , Animais , Antagonistas de Dopamina/farmacologia , Hormônios/farmacologia , Cavalos , Doenças da Hipófise/sangue , Doenças da Hipófise/metabolismo , Adeno-Hipófise Parte Intermédia
18.
Vet Surg ; 40(7): 875-80, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22380671

RESUMO

OBJECTIVE: To determine changes in drill bit performance attributable to application of a triaxially resilient, hard-carbon thin film. STUDY DESIGN: In vitro mechanical study. METHODS: Five matched pairs of control bits and bits with a carbon nanofilm applied were tested in equine cortical bone and a synthetic bone substrate. Thirty sequential holes were drilled with each bit. Drilling time was recorded for all holes. Maximum substrate temperature was measured with infrared thermography for holes 1, 15, and 30. Drilling time, prolongation of drilling time over successive uses, and maximum substrate temperature were compared between control and test bits in each substrate. RESULTS: Drilling time was significantly reduced with test bits in both substrates. Drilling time over successive osteotomies increased more slowly with test bits than with control bits. Test bits generated significantly lower substrate temperatures during drilling. CONCLUSIONS: Bits with the carbon nanofilm completed osteotomy faster and generated less heat than control bits. Test bits also had less degradation of drilling performance with repeated use.


Assuntos
Carbono/química , Temperatura Alta , Teste de Materiais , Membranas Artificiais , Instrumentos Cirúrgicos , Animais , Substitutos Ósseos , Osso e Ossos , Cavalos
19.
Front Endocrinol (Lausanne) ; 12: 656054, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267726

RESUMO

With the intention of isolating the susceptibility of modeling methodology to influence our investigation of the infusion data, we used three kinetic approaches to our models: a simple approach, a unit approach, and a novel approach. The simple approach used exclusively built-in modeling features of the software in terms of units of the infusion dilution (mmol/L), as well as in terms of the precision of switching the infusion on and off. The unit approach used the same switching mechanism as the simple approach, but the units were modeled in those of the infusion (e.g., mmol/kg). Thirdly with the novel approach, we used an automated approach to controlling the infusion, in the sense that as the modeling mechanism sensed the slowdown of the infusion, it was gradually turned off. The units of the analysis for the novel approach were exactly the same as those deployed in the unit approach. Our objective here was to see if common pharmacokinetic parameters were seriously impacted by the particular modeling method.


Assuntos
Ácido Láctico/administração & dosagem , Ácido Láctico/metabolismo , Taxa de Depuração Metabólica , Modelos Estatísticos , Animais , Humanos , Bombas de Infusão , Cinética
20.
Front Endocrinol (Lausanne) ; 12: 789390, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777263

RESUMO

[This corrects the article DOI: 10.3389/fendo.2021.625701.].

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