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1.
Intern Med J ; 52(8): 1434-1436, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35973960

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Tipo 1 , Trasplante de Islotes Pancreáticos , Adulto , Australia/epidemiología , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/cirugía , Humanos , Terapia de Inmunosupresión , Insulina , Anticuerpos Insulínicos
2.
Front Endocrinol (Lausanne) ; 12: 789390, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34777263

RESUMEN

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

3.
Front Endocrinol (Lausanne) ; 12: 611512, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34335462

RESUMEN

The authors' perspective is described regarding modifications made in their clinic to glucose challenge protocols and mathematical models in order to estimate insulin secretion, insulin sensitivity and glucose effectiveness in patients living with Insulin-Requiring Diabetes and patients who received Pancreatic Islet Transplants to treat Type I diabetes (T1D) with Impaired Awareness of Hypoglycemia. The evolutions are described of protocols and models for use in T1D, and Insulin-Requiring Type 2 Diabetes (T2D) that were the basis for studies in the Islet Recipients. In each group, the need for modifications, and how the protocols and models were adapted is discussed. How the ongoing application of the adaptations is clarifying the Islet pathophysiology in the Islet Transplant Recipients is outlined.


Asunto(s)
Diabetes Mellitus Tipo 1/terapia , Trasplante de Islotes Pancreáticos , Modelos Biológicos , Receptores de Trasplantes , Humanos , Resistencia a la Insulina , Secreción de Insulina
4.
EClinicalMedicine ; 37: 100934, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34386736

RESUMEN

BACKGROUND: While the effects of prolonged sleep deprivation (≥24 h) on seizure occurrence has been thoroughly explored, little is known about the effects of day-to-day variations in the duration and quality of sleep on seizure probability. A better understanding of the interaction between sleep and seizures may help to improve seizure management. METHODS: To explore how sleep and epileptic seizures are associated, we analysed continuous intracranial electroencephalography (EEG) recordings collected from 10 patients with refractory focal epilepsy undergoing ordinary life activities between 2010 and 2012 from three clinical centres (Austin Health, The Royal Melbourne Hospital, and St Vincent's Hospital of the Melbourne University Epilepsy Group). A total of 4340 days of sleep-wake data were analysed (average 434 days per patient). EEG data were sleep scored using a semi-automated machine learning approach into wake, stages one, two, and three non-rapid eye movement sleep, and rapid eye movement sleep categories. FINDINGS: Seizure probability changes with day-to-day variations in sleep duration. Logistic regression models revealed that an increase in sleep duration, by 1·66 ± 0·52 h, lowered the odds of seizure by 27% in the following 48 h. Following a seizure, patients slept for longer durations and if a seizure occurred during sleep, then sleep quality was also reduced with increased time spent aroused from sleep and reduced rapid eye movement sleep. INTERPRETATION: Our results suggest that day-to-day deviations from regular sleep duration correlates with changes in seizure probability. Sleeping longer, by 1·66 ± 0·52 h, may offer protective effects for patients with refractory focal epilepsy, reducing seizure risk. Furthermore, the occurrence of a seizure may disrupt sleep patterns by elongating sleep and, if the seizure occurs during sleep, reducing its quality.

5.
Front Endocrinol (Lausanne) ; 12: 656054, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34267726

RESUMEN

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.


Asunto(s)
Ácido Láctico/administración & dosificación , Ácido Láctico/metabolismo , Tasa de Depuración Metabólica , Modelos Estadísticos , Animales , Humanos , Bombas de Infusión , Cinética
6.
Front Endocrinol (Lausanne) ; 12: 625701, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33815283

RESUMEN

Glucose and free fatty acids (FFA) are essential nutrients that are both partly regulated by insulin. Impaired insulin secretion and insulin resistance are hallmarks of aberrant glucose disposal, and type 2 diabetes (T2DM). In the current study, a novel model of FFA kinetics is proposed to estimate the role insulin action on FFA lipolysis and oxidation allowing estimation of adipose tissue insulin sensitivity (SIFFA ). Twenty-five normal volunteers were recruited for the current study. To participate, volunteers had to be less than 40 years of age and have a body mass index (BMI) < 30 kg/m2, and be free of medical comorbidity. The proposed model of FFA kinetics was used to analyze the data derived from the insulin-modified FSIGT. Mean fractional standard deviations of the parameter estimates were all less than 20%. Standardized residuals of the fit of the model to the FFA temporal data were randomly distributed, with only one estimated point lying outside the 2-standard deviation range, suggesting an acceptable fit of the model to the FFA data. The current study describes a novel one-compartment non-linear model of FFA kinetics during an FSIGT that provides an FFA metabolism insulin sensitivity parameter (SIFFA ). Furthermore, the models suggest a new role of glucose as the modulator of FFA disposal. Estimates of SIFFA confirmed previous findings that FFA metabolism is more sensitive to changes in insulin than glucose metabolism. Novel derived indices of insulin sensitivity of FFA (SIFFA ) were correlated with minimal model indices. These associations suggest a cooperative rather than competitive interplay between the two primary nutrients (glucose and FFA) and allude to the FFA acting as the buffer, such that glucose homeostasis is maintained.


Asunto(s)
Tejido Adiposo/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Glucosa/metabolismo , Resistencia a la Insulina/fisiología , Secreción de Insulina/fisiología , Insulina/metabolismo , Adulto , Glucemia/metabolismo , Índice de Masa Corporal , Homeostasis/fisiología , Humanos , Lipólisis/fisiología , Modelos Teóricos , Adulto Joven
7.
J Vet Pharmacol Ther ; 44(3): 349-358, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33305843

RESUMEN

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.


Asunto(s)
Teorema de Bayes , Administración Oral , Administración Tópica , Animales , Caballos
8.
Metabolism ; 110: 154298, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32569679

RESUMEN

OBJECTIVE: This work aimed to estimate population-level insulin sensitivity (SI) from 2-hour oral glucose tolerance tests (OGTT) with less than 7 samples. RESEARCH DESIGN AND METHODS: The current methodology combines the OGTT mathematical model developed by Dalla Man et al., with nonlinear multilevel (NLML) statistical model to estimate population-level insulin sensitivity (SI) from sparsely sampled datasets (3 or 4 samples per subject obtained in 120 min). To validate our novel methodology of population SI estimation, we simulated 50 virtual subjects. We simulated 10 observations per subject over 240 minutes. After estimating their SI using the OGTT model, the virtual subjects were split into two groups, subjects with SI above the average and ones with below average. Subsequently, the simulated data were analyzed using statistical software and employing a t-test. The mean estimates of population SI for the two groups of virtual subjects and their respective 95% CI were compared to the estimates obtained with our novel NLML group SI estimates obtained using the 3 and 4 time points per subject. To further validate the performance of the novel NLML model, a set of 34 prediabetic and 30 diabetic subjects with T2D was used. As outlined above for the in-silico subjects, differences between the prediabetic and T2D subjects in regard to SI was assessed using the classical two-stage approach (individual SI estimation followed by statistical comparison of the two groups). The average estimates obtained with the classical two-stage approach were compared to the group estimated obtained with the NLML approach using 3 (0, 60, and 120 minutes) points per subject obtained in 120 minutes. RESULTS: Unique and identifiable individual estimates of SI were obtained for all virtual subjects. In comparison to the subjects with above average SI (n=25), the subjects with simulated below average SI (n=25) exhibited significantly lower insulin sensitivity (P<0.001). Our novel NLML population model confirmed these findings (4-point OGTT: P<0.001; 3-point OGTT: P<0.001). In a similar fashion to the one outlined for the virtual subjects, the median insulin sensitivities estimated with the classical two-stage approach were different between the prediabetic (n=34) and T2D subjects (n=32, P=0.004). Using 3 points per subject, our novel NLML model confirmed these findings (P<0.001). CONCLUSIONS: The population estimates of SI from OGTT data is an effective tool to assess population insulin sensitivity and assess differences that may not be possible when calculating individual SI or when less than 7 samples are available.


Asunto(s)
Prueba de Tolerancia a la Glucosa , Resistencia a la Insulina , Adulto , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Estado Prediabético/metabolismo
9.
J Vet Pharmacol Ther ; 43(6): 557-564, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32424949

RESUMEN

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.


Asunto(s)
Caballos/metabolismo , Hipnóticos y Sedantes/farmacocinética , Xilazina/farmacocinética , Animales , Área Bajo la Curva , Estudios Cruzados , Esquema de Medicación , Femenino , Semivida , Caballos/sangre , Hipnóticos y Sedantes/sangre , Inyecciones Intravenosas , Masculino , Xilazina/sangre
10.
Am J Physiol Endocrinol Metab ; 318(3): E392-E404, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31910030

RESUMEN

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.


Asunto(s)
Ácidos Grasos no Esterificados/metabolismo , Hiperglucemia/metabolismo , Hipoglucemia/metabolismo , Resistencia a la Insulina , Adulto , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Método Doble Ciego , Femenino , Glucosa/farmacología , Prueba de Tolerancia a la Glucosa , Humanos , Secreción de Insulina/efectos de los fármacos , Lípidos/sangre , Masculino , Síndrome Metabólico/metabolismo , Persona de Mediana Edad
11.
J Vet Pharmacol Ther ; 42(5): 541-547, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31325161

RESUMEN

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.


Asunto(s)
Glucemia , Hormonas/farmacología , Caballos/sangre , Insulina/sangre , Somatostatina/farmacología , Administración Intravenosa , Animales , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Hormonas/administración & dosificación , Inyecciones Subcutáneas , Somatostatina/administración & dosificación
12.
Diabetes Obes Metab ; 21(8): 2012-2016, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31050161

RESUMEN

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.


Asunto(s)
Enfermedad de la Arteria Coronaria/fisiopatología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/farmacología , Lipólisis/efectos de los fármacos , Liraglutida/farmacología , Obesidad/fisiopatología , Oxidación-Reducción/efectos de los fármacos , Anciano , Glucemia/efectos de los fármacos , Enfermedad de la Arteria Coronaria/complicaciones , Estudios Cruzados , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/fisiopatología , Método Doble Ciego , Quimioterapia Combinada , Ácidos Grasos no Esterificados/sangre , Femenino , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Metformina/farmacología , Persona de Mediana Edad , Obesidad/complicaciones , Resultado del Tratamiento
13.
Vet Dermatol ; 30(3): 255-e78, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30828914

RESUMEN

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.


Asunto(s)
Dermatitis Atópica/veterinaria , Desensibilización Inmunológica/veterinaria , Enfermedades de los Caballos/inmunología , Inmunoglobulina E/inmunología , Alérgenos/inmunología , Animales , Dermatitis Atópica/terapia , Ensayo de Inmunoadsorción Enzimática , Enfermedades de los Caballos/terapia , Caballos/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Pruebas Intradérmicas/veterinaria , Estudios Longitudinales , Propiedad , Proyectos Piloto
14.
Hum Reprod ; 34(2): 335-344, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30576500

RESUMEN

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.


Asunto(s)
Ácidos Grasos no Esterificados/metabolismo , Resistencia a la Insulina , Obesidad/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Adolescente , Adulto , Glucemia/metabolismo , Índice de Masa Corporal , Estudios Transversales , Ácidos Grasos no Esterificados/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Lipólisis , Obesidad/sangre , Obesidad/complicaciones , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/complicaciones , Estudios Prospectivos , Adulto Joven
15.
J Vet Pharmacol Ther ; 41(6): 825-837, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30028024

RESUMEN

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.


Asunto(s)
Anestésicos Locales/farmacocinética , Caballos/metabolismo , Lidocaína/análogos & derivados , Lidocaína/farmacocinética , Anestésicos Locales/administración & dosificación , Animales , Área Bajo la Curva , Estudios Cruzados , Vías de Administración de Medicamentos , Femenino , Semivida , Caballos/sangre , Lidocaína/administración & dosificación , Lidocaína/farmacología , Masculino , Distribución Aleatoria
16.
Am J Vet Res ; 79(2): 191-198, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29359971

RESUMEN

OBJECTIVE To assess insulin, glucagon, and somatostatin expression within pancreatic islets of horses with and without insulin resistance. ANIMALS 10 insulin-resistant horses and 13 insulin-sensitive horses. PROCEDURES For each horse, food was withheld for at least 10 hours before a blood sample was collected for determination of serum insulin concentration. Horses with a serum insulin concentration < 20 µU/mL were assigned to the insulin-sensitive group, whereas horses with a serum insulin concentration > 20 µU/mL underwent a frequently sampled IV glucose tolerance test to determine sensitivity to insulin by minimal model analysis. Horses with a sensitivity to insulin < 1.0 × 10-4 L•min-1•mU-1 were assigned to the insulin-resistant group. All horses were euthanized with a barbiturate overdose, and pancreatic specimens were harvested and immunohistochemically stained for determination of insulin, glucagon, and somatostatin expression in pancreatic islets. Islet hormone expression was compared between insulin-resistant and insulin-sensitive horses. RESULTS Cells expressing insulin, glucagon, and somatostatin made up approximately 62%, 12%, and 7%, respectively, of pancreatic islet cells in insulin-resistant horses and 64%, 18%, and 9%, respectively, of pancreatic islet cells in insulin-sensitive horses. Expression of insulin and somatostatin did not differ between insulin-resistant and insulin-sensitive horses, but the median percentage of glucagon-expressing cells in the islets of insulin-resistant horses was significantly less than that in insulin-sensitive horses. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that, in insulin-resistant horses, insulin secretion was not increased but glucagon production might be downregulated as a compensatory response to hyperinsulinemia.


Asunto(s)
Glucagón/metabolismo , Enfermedades de los Caballos/metabolismo , Resistencia a la Insulina , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Somatostatina/metabolismo , Animales , Femenino , Caballos , Inmunohistoquímica/veterinaria , Masculino
17.
J Vet Emerg Crit Care (San Antonio) ; 27(5): 539-547, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28877414

RESUMEN

OBJECTIVE: Evaluate the analgesic properties and pharmacokinetics of transdermal fentanyl patches (TFPs) in goats. DESIGN: Prospective, randomized study. SETTING: Preclinical Testing Facility at a University Teaching Hospital. ANIMALS: Thirty-four adult female Boer-cross goats. INTERVENTIONS: Goats underwent surgery as part of a concurrent orthopedic research study. Twelve hours prior to surgery, each goat received a TFP (target dosage of 2.5 µg/kg/h), or a placebo patch with analgesia provided by buprenorphine (0.01 mg/kg, IM, q 6 h). Patches were removed after 72 hours. Blood was sampled at specified intervals, up to 84 hours following TFP placement. Plasma concentrations of fentanyl (FEN) were determined using liquid chromatography-mass spectrometry. Postoperative pain assessments were performed by two independent blinded observers. MEASUREMENTS AND MAIN RESULTS: TFPs were applied at a mean (± standard deviation, SD) dose of 2.54 ± 0.36 µg/kg/h. No adverse events occurred. Pain scores between TFP and BUP groups were not significantly different at any time point. Mean plasma FEN concentration (± SD) 2 hours following patch application was 1.06 ± 0.85 ng/mL, and remained above 0.5 ng/mL for 40 hours. Maximum mean plasma FEN concentration (Cmax ) was 1.84 (ranging from 0.81 to 3.35) ng/mL with average time to maximum concentration (Tmax ) of 12 hours after patch application. CONCLUSIONS: TFP resulted in consistent FEN absorption and plasma concentrations within the human and ovine therapeutic ranges. Pain scores for goats administered TFP were not different than those administered buprenorphine. Ease of administration, duration of analgesia, and decreased dosing frequency make TFPs an attractive option for pain management in goats.


Asunto(s)
Analgésicos Opioides/farmacología , Fentanilo/farmacología , Enfermedades de las Cabras/tratamiento farmacológico , Dolor Postoperatorio/veterinaria , Administración Cutánea , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/farmacocinética , Animales , Femenino , Fentanilo/administración & dosificación , Fentanilo/farmacocinética , Cabras , Dolor Postoperatorio/tratamiento farmacológico , Estudios Prospectivos
18.
Oncotarget ; 8(34): 57278-57301, 2017 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-28915670

RESUMEN

BACKGROUND: Prostate cancer (PCa) management can benefit from novel concepts/biomarkers for reducing the current 20-30% chance of false-negative diagnosis with standard histopathology of biopsied tissue. METHOD: We explored the potential of selected epigenetic markers in combination with validated histopathological markers, 3D high-content imaging, cell-by-cell analysis, and probabilistic classification in generating novel detailed maps of biomarker heterogeneity in patient tissues, and PCa diagnosis. We used consecutive biopsies/radical prostatectomies from five patients for building a database of ∼140,000 analyzed cells across all tissue compartments and for model development; and from five patients and the two well-characterized HPrEpiC primary and LNCaP cancer cell types for model validation. RESULTS: Principal component analysis presented highest covariability for the four biomarkers 4',6-diamidino-2-phenylindole, 5-methylcytosine, 5-hydroxymethylcytosine, and alpha-methylacyl-CoA racemase in the epithelial tissue compartment. The panel also showed best performance in discriminating between normal and cancer-like cells in prostate tissues with a sensitivity and specificity of 85%, correctly classified 87% of HPrEpiC as healthy and 99% of LNCaP cells as cancer-like, identified a majority of aberrant cells within histopathologically benign tissues at baseline diagnosis of patients that were later diagnosed with adenocarcinoma. Using k-nearest neighbor classifier with cells from an initial patient biopsy, the biomarkers were able to predict cancer stage and grade of prostatic tissue that occurred at later prostatectomy with 79% accuracy. CONCLUSION: Our approach showed favorable diagnostic values to identify the portion and pathological category of aberrant cells in a small subset of sampled tissue cells, correlating with the degree of malignancy beyond baseline.

19.
J Am Vet Med Assoc ; 250(12): 1432-1439, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28569630

RESUMEN

OBJECTIVE To develop a risk prediction model for factors associated with an SeM-specific antibody titer ≥ 3,200 in horses after naturally occurring outbreaks of Streptococcus equi subsp equi infection and to validate this model. DESIGN Case-control study. ANIMALS 245 horses: 57 horses involved in strangles outbreaks (case horses) and 188 healthy horses (control horses). PROCEDURES Serum samples were obtained from the 57 cases over a 27.5-month period after the start of outbreaks; serum samples were obtained once from the 188 controls. A Bayesian mixed-effects logistic regression model was used to assess potential risk factors associated with an antibody titer ≥ 3,200 in the case horses. A cutoff probability for an SeM-specific titer ≥ 3,200 was determined, and the model was externally validated in the control horses. Only variables with a 95% credibility interval that did not overlap with a value of 1 were considered significant. RESULTS 9 of 57 (6%) case horses had at least 1 titer ≥ 3,200, and 7 of 188 (3.7%) of control horses had a titer ≥ 3,200. The following variables were found to be significantly associated with a titer ≥ 3,200 in cases: farm size > 20 horses (OR, 0.11), history of clinically evident disease (OR, 7.92), and male sex (OR, 0.11). The model had 100% sensitivity but only 24% specificity when applied to the 188 control horses (area under the receiver operating characteristic curve = 0.62.) CONCLUSIONS AND CLINICAL RELEVANCE Although the Bayesian mixed-effects logistic regression model developed in this study did not perform well, it may prove useful as an initial screening tool prior to vaccination. We suggest that SeM-specific antibody titer be measured prior to vaccination when our model predicts a titer ≥ 3,200.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Brotes de Enfermedades/veterinaria , Enfermedades de los Caballos/epidemiología , Infecciones Estreptocócicas/veterinaria , Streptococcus equi/inmunología , Animales , Especificidad de Anticuerpos , Estudios de Casos y Controles , Brotes de Enfermedades/prevención & control , Femenino , Enfermedades de los Caballos/microbiología , Enfermedades de los Caballos/prevención & control , Caballos , Masculino , Modelos Teóricos , Pennsylvania/epidemiología , Factores de Riesgo , Sensibilidad y Especificidad , Infecciones Estreptocócicas/epidemiología
20.
Vet Surg ; 46(5): 700-704, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28462516

RESUMEN

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.


Asunto(s)
Cartílago Aritenoides/cirugía , Laringoplastia/veterinaria , Prótesis e Implantes/veterinaria , Técnicas de Sutura/veterinaria , Animales , Cadáver , Caballos , Laringoplastia/métodos , Laringe/cirugía , Anclas para Sutura , Suturas
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