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1.
Transplant Direct ; 10(1): e1566, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38111836

RESUMEN

Background: Trabecular bone score (TBS) is a new tool to assess trabecular bone microarchitecture based on standard dual-energy x-ray absorptiometry (DXA) of lumbar spine images. TBS may be important to assess bone quality and fracture susceptibility in kidney transplant recipients (KTRs). This study aimed to investigate the effect of different bone therapies on TBS in KTRs. Methods: We reanalyzed DXA scans to assess TBS in 121 de novo KTRs at baseline, 10 wk, and 1 y. This cohort, between 2007 and 2009, participated in a randomized, placebo-controlled trial evaluating the effect of ibandronate versus placebo in addition to vitamin D and calcium. Results: Although bone mineral density (BMD) Z scores showed a subtle decrease in the first weeks, TBS Z scores increased from baseline to 10 wk for both treatment groups, followed by a slight decline at 12 mo. When comparing treatment groups and adjusting for baseline TBS, there were no differences found in TBS at 12 mo (P = 0.419). Correlation between TBS and BMD at baseline was weak (Spearman's ρ = 0.234, P = 0.010), and change in TBS was not correlated with changes in lumbar spine BMD in either of the groups (ρ = 0.003, P = 0.973). Conclusions: Treatment with ibandronate or vitamin D and calcium did not affect bone quality as measured by TBS in de novo KTRs, but TBS increased early, irrespective of intervention. Changes in TBS and BMD during the study period were not correlated, indicating that these measurements reflect different aspects of bone integrity. TBS may complement BMD assessment in identifying KTRs with a high fracture risk.

2.
Kidney Med ; 5(1): 100574, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36593877

RESUMEN

Rationale & Objective: In kidney transplant recipients (KTRs), a belatacept-based immunosuppressive regimen is associated with beneficial effects on cardiovascular (CV) risk factors compared with calcineurin inhibitor (CNI)-based regimens. Our objective was to compare the calculated CV risk between belatacept and CNI (predominantly tacrolimus) treatments using a validated model developed for KTRs. Study Design: Prospective, randomized, open-label, parallel-group, investigator-initiated, international multicenter trial. Setting & Participants: KTRs aged 18-80 years with a stable graft function (estimated glomerular filtration rate > 20 mL/min/1.73 m2), 3-60 months after transplantation, treated with tacrolimus or cyclosporine A, were eligible for inclusion. Intervention: Continuation with a CNI-based regimen or switch to belatacept for 12 months. Outcomes: Comparison of the change in the estimated 7-year risk of major adverse CV events and all-cause mortality, changes in traditional markers of CV health, as well as measures of arterial stiffness. Results: Among the 105 KTRs randomized, we found no differences between the treatment groups in the predicted risk for major adverse CV events or mortality. Diastolic blood pressure, measured both centrally by using a SphygmoCor device and peripherally, was lower after the belatacept treatment than after the CNI treatment. The mean changes in traditional cardiovascular (CV) risk factors, including kidney transplant function, were otherwise similar in both the treatment groups. The belatacept group had 4 acute rejection episodes; 2 were severe rejections, of which 1 led to graft loss. Limitations: The heterogeneous baseline estimated glomerular filtration rate and time from transplantation to trial enrollment in the participants. A limited study duration of 1 year. Conclusions: We found no effects on the calculated CV risk by switching to the belatacept treatment. Participants in the belatacept group had not only lower central and peripheral diastolic blood pressure but also a higher rejection rate. Funding: The trial has received a financial grant from Bristol-Myers Squibb. Trial Registration: EudraCT no. 2013-001178-20.

3.
Neuropsychopharmacology ; 44(2): 306-313, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30323359

RESUMEN

Little is known about how intranasally administered oxytocin reaches the brain and modulates social behavior and cognition. Pupil dilation is a sensitive index of attentional allocation and effort, and inter-individual variability in pupil diameter during performance of social-cognitive tasks may provide a better assessment of pharmacological effects on the brain than behavioral measures. Here, we leverage the close relationship between pupil and neural activity to inform our understanding of nose-to-brain oxytocin routes and possible dose-response relationships. To this end, we assessed pupil diameter data from a previously reported functional magnetic resonance imaging (fMRI) study under four treatment conditions-including two different doses of intranasal oxytocin using a novel Breath Powered nasal device, intravenous (IV) oxytocin, and placebo-and investigated the association with amygdala activation in response to emotional stimuli. The study used a randomized, double-blind, double-dummy, crossover design, with 16 healthy male adults administering a single-dose of these four treatments. A significant main effect of treatment condition on pupil diameter was observed. Posthoc tests revealed reduced pupil diameter after 8IU intranasal oxytocin compared to placebo, but no significant difference between 8IU intranasal oxytocin and either 24IU intranasal oxytocin or IV oxytocin treatment conditions. Analysis also showed a significant relationship between pupil diameter and right amygdala activation after 8IU intranasal oxytocin. Although there was no significant difference between 8IU intranasal oxytocin and IV oxytocin on right amygdala activity and pupil diameter, the significant difference between 8IU intranasal oxytocin and placebo is consistent with the hypothesis that oxytocin can travel to the brain via a nose-to-brain route.


Asunto(s)
Amígdala del Cerebelo/efectos de los fármacos , Reconocimiento Facial/efectos de los fármacos , Oxitocina/administración & dosificación , Pupila/efectos de los fármacos , Percepción Social , Administración Intranasal , Adulto , Amígdala del Cerebelo/diagnóstico por imagen , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Expresión Facial , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Adulto Joven
4.
Ther Deliv ; 9(7): 515-525, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29943688

RESUMEN

The neuropeptide oxytocin plays an evolutionarily conserved role in mammalian social behavior. Despite striking effects on animal social behavior after intracerebroventricular drug delivery, this delivery mode is impractical in humans. Intranasal oxytocin delivery provides a noninvasive alternative to increase central oxytocin activity, and has shown promise as a treatment for psychiatric illnesses. Intranasal oxytocin delivery is purported to increase central oxytocin concentrations via channels surrounding trigeminal and olfactory nerve fibers, which may facilitate increased activity at central oxytocin receptors. This report outlines the evidence for intranasal oxytocin delivery increasing central concentrations or activity, identifies current knowledge gaps and highlights future research opportunities. Recent efforts to enhance intranasal oxytocin delivery via improved intranasal delivery technology and dose-ranging studies are discussed.


Asunto(s)
Encéfalo/efectos de los fármacos , Trastornos Mentales/tratamiento farmacológico , Mucosa Nasal/metabolismo , Oxitocina/administración & dosificación , Absorción Fisiológica , Administración Intranasal/métodos , Administración Intranasal/tendencias , Animales , Conducta Animal/efectos de los fármacos , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Excipientes/farmacocinética , Humanos , Oxitocina/farmacocinética , Conducta Social
5.
Horm Behav ; 102: 85-92, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29750971

RESUMEN

Oxytocin plays an important role in social behavior. Thus, there has been significant research interest for the role of the oxytocin system in several psychiatric disorders, and the potential of intranasal oxytocin administration to treat social dysfunction. Measurement of oxytocin concentrations in saliva are sometimes used to approximate peripheral levels of oxytocin; however, the validity of this approach is unclear. In this study, saliva and plasma oxytocin was assessed after two doses of Exhalation Delivery System delivered intranasal oxytocin (8 IU and 24 IU), intravenous oxytocin (1 IU) and placebo in a double-dummy, within-subjects design with men. We found that intranasal oxytocin (8 IU and 24 IU) administration increased saliva oxytocin concentrations in comparison to saliva oxytocin concentration levels after intravenous and placebo administration. Additionally, we found that saliva oxytocin concentrations were not significantly associated with plasma oxytocin concentrations after either intranasal or intravenous oxytocin administration. Altogether, we suggest that saliva oxytocin concentrations do not accurately index peripheral oxytocin after intranasal or intravenous oxytocin administration, at least in men. The data indicates that elevated oxytocin saliva levels after nasal delivery primarily reflect exogenous administered oxytocin that is cleared from the nasal cavity to the oropharynx, and is therefore a weak surrogate for peripheral blood measurements.


Asunto(s)
Oxitocina/administración & dosificación , Oxitocina/análisis , Oxitocina/sangre , Oxitocina/farmacocinética , Saliva/química , Administración Intranasal , Adolescente , Adulto , Análisis Químico de la Sangre , Método Doble Ciego , Humanos , Masculino , Rociadores Nasales , Factores Sexuales , Conducta Social , Factores de Tiempo , Adulto Joven
6.
Clin Transplant ; 31(12)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28972673

RESUMEN

A serum test called T50 assesses the overall propensity for calcification of the blood and is associated with cardiovascular outcomes. We aimed to examine T50 over time in kidney transplant recipients and also address any effects of ibandronate. Serum samples taken from kidney transplant patients included in a prospective, randomized placebo controlled study of ibandronate were analyzed in retrospect. Adequate analyses were performed at baseline (approximately 3 weeks after transplantation) in 129 patients, at 10 weeks in 127 patients and at 1 year in 123 patients. There were no statistical differences between ibandronate and placebo treatment in terms of T50 at 10 weeks (P = .094) or at 1 year (P = .116). Baseline T50 was a significant covariate (P < .0001) for T50 scores at 10 weeks and 1 year. In the total cohort, there was a highly significant (P < .0001) increase in T50 of 26.6% after 10 weeks and T50 remained stable after 1 year. T50 change was inversely correlated to phosphate of -0.515 (P < .0001) and to change in serum albumin (P < .03). We found that T50 increased from baseline to 10 weeks after transplantation with no further change after 1 year. Ibandronate had no effect on T50 .


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Calcinosis/tratamiento farmacológico , Difosfonatos/uso terapéutico , Supervivencia de Injerto/efectos de los fármacos , Fallo Renal Crónico/cirugía , Trasplante de Riñón/métodos , Puntaje de Propensión , Calcinosis/epidemiología , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Ácido Ibandrónico , Pruebas de Función Renal , Masculino , Persona de Mediana Edad , Noruega/epidemiología , Pronóstico , Estudios Prospectivos , Factores de Riesgo
7.
Clin Pharmacol Drug Dev ; 6(6): 584-591, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28032481

RESUMEN

The purpose of the present trial was to evaluate safety, tolerability, and effect on systolic blood pressure (SBP) of SER100 in a small group of patients with isolated systolic hypertension (ISH) in treatment with at least 1 antihypertensive drug. Eligible patients were randomized to either SER100 (10 mg) or placebo in a crossover design, and 2 doses were given subcutaneously (SC), 8 hours apart, on 2 consecutive days. On all treatment days patients were monitored with an ambulatory blood pressure measurement device for 12 daytime hours. Seventeen patients completed treatment. There were no serious or severe adverse events. Relative to placebo SER100 induced an average reduction of SBP during the 2 treatment days of 7.0 mm Hg (P = 0.0032), whereas the average reduction of diastolic blood pressure (DBP) over the same period was 3.8 mm Hg (P = 0.0011). For patients with ISH, this short-term cross-over study of SC SER100 demonstrated an acceptable safety profile and consistent, significant lowering of SBP and DBP. As initial clinical proof of concept for a new class of drugs, a nociceptin agonist peptide, the results were encouraging and warrant further research.


Asunto(s)
Antihipertensivos/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Oligopéptidos/administración & dosificación , Anciano , Antihipertensivos/efectos adversos , Antihipertensivos/farmacología , Monitoreo Ambulatorio de la Presión Arterial , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Oligopéptidos/efectos adversos , Oligopéptidos/farmacología , Receptores Opioides/agonistas , Receptor de Nociceptina
8.
Acta Neuropsychiatr ; 29(5): 315-321, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27923411

RESUMEN

OBJECTIVE: The neuropeptides oxytocin (OT) and arginine vasopressin (AVP) play important and interrelated roles in modulating mammalian social behaviour. While the OT system has received considerable research attention for its potential to treat psychiatric symptoms, comparatively little is known about the role of the AVP system in human social behaviour. To better understand the intraindividual stability of basal AVP, the present study assessed the reproducibility of basal plasma AVP concentrations. METHODS: Basal plasma AVP was assessed at four sampling points separated by 8 days, on average, in 16 healthy adult males. RESULTS: Only one out of six comparisons revealed strong evidence for reproducibility of basal AVP concentrations (visit 2 vs. visit 4: r=0.8, p0.1). The concordance correlation coefficient [0.15, 95% CI (-0.55, 0.73)] also revealed poor overall reproducibility. CONCLUSION: Poor reliability of basal AVP concentrations suggests future work covarying AVP with trait markers should proceed with careful consideration of intraindividual fluctuations.


Asunto(s)
Arginina Vasopresina/sangre , Adulto , Humanos , Masculino , Reproducibilidad de los Resultados , Adulto Joven
9.
Psychoneuroendocrinology ; 69: 180-8, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27107209

RESUMEN

UNLABELLED: It is unclear if and how exogenous oxytocin (OT) reaches the brain to improve social behavior and cognition and what is the optimal dose for OT response. To better understand the delivery routes of intranasal OT administration to the brain and the dose-response, we compared amygdala response to facial stimuli by means of functional magnetic resonance imaging (fMRI) in four treatment conditions, including two different doses of intranasal OT using a novel Breath Powered device, intravenous (IV) OT, which provided similar concentrations of blood plasma OT, and placebo. We adopted a randomized, double-blind, double-dummy, crossover design, with 16 healthy male adults administering a single-dose of these four treatments. We observed a treatment effect on right amygdala activation during the processing of angry and happy face stimuli, with pairwise comparisons revealing reduced activation after the 8IU low dose intranasal treatment compared to placebo. These data suggest the dampening of amygdala activity in response to emotional stimuli occurs via direct intranasal delivery pathways rather than across the blood-brain barrier via systemically circulating OT. TRIAL REGISTRATION: This trial is registered at the U.S. National Institutes of Health clinical trial registry (www.clinicaltrials.gov; NCT01983514) and as EudraCT no. 2013-001608-12.


Asunto(s)
Amígdala del Cerebelo/efectos de los fármacos , Reconocimiento Facial/efectos de los fármacos , Oxitocina/farmacología , Administración Intranasal , Adulto , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Cognición/efectos de los fármacos , Cognición/fisiología , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Emociones/fisiología , Expresión Facial , Humanos , Imagen por Resonancia Magnética , Masculino , Oxitocina/metabolismo , Conducta Social , Adulto Joven
10.
Clin Trials ; 9(2): 164-75, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22297620

RESUMEN

BACKGROUND: In active run-in trials, where patients may be excluded after a run-in period based on their response to the treatment, it is implicitly assumed that patients have individual treatment effects. If individual patient data are available, active run-in trials can be modelled using patient-specific random effects. With more than one trial on the same medication available, one can obtain a more precise overall treatment effect estimate. METHODS: We present a model for joint analysis of a two-sequence, four-period cross-over trial (AABB/BBAA) and a three-sequence, two-period active run-in trial (AB/AA/A), where the aim is to investigate the effect of a new treatment for patients with pain due to osteoarthritis. RESULTS: Our approach enables us to separately estimate the direct treatment effect for all patients, for the patients excluded after the active run-in trial prior to randomisation, and for the patients who completed the active run-in trial. A similar model approach can be used to analyse other types of run-in trials, but this depends on the data and type of other trials available. LIMITATIONS: We assume equality of the various carry-over effects over time. CONCLUSIONS: The proposed approach is flexible and can be modified to handle other designs. Our results should be encouraging for those responsible for planning cost-efficient clinical development programmes.


Asunto(s)
Estudios Cruzados , Osteoartritis de la Rodilla/tratamiento farmacológico , Evaluación de Resultado en la Atención de Salud/métodos , Sesgo , Humanos , Modelos Estadísticos , Osteoartritis de la Rodilla/fisiopatología , Manejo del Dolor/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Br J Nutr ; 91(3): 393-401, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15005825

RESUMEN

The objective was to study whether a yoghurt containing isolated soya protein with standardised levels of isoflavones, cotyledon soya fibres and soya phospholipids is more effective in lowering total and LDL-cholesterol than a placebo. One hundred and forty-three subjects were randomised to the soya group (n 69) or to the placebo (n 74). The mean baseline levels were 7.6 and 5.1 mmol/l for total and LDL-cholesterol, respectively. Fasting serum lipoproteins were assessed five times during the 8-week intervention period, and 4 weeks thereafter. The results were analysed by a mixed model for unbalanced repeated measurements. During the intervention, there were highly significant differences in lipid-lowering effect in favour of the active soya intervention group compared with the control group. The significant differences were for total cholesterol (estimated mean difference 0.40 mmol/l; P<0.001), LDL-cholesterol (0.39 mmol/l; P<0.001), non-HDL-cholesterol (0.40 mmol/l; P<0.001) and for the total:HDL-cholesterol ratio (0.23; P=0.005). There was no difference in the effects on HDL-cholesterol, triacylglycerols or homocysteine. The lipid-lowering effect occurred within 1-2 weeks of intervention, and was not due to weight loss. The safety profile for active soya was similar to the placebo group, except for gastrointestinal symptoms, which caused a significantly higher dropout rate (fourteen v. three subjects) among the subjects taking active soya.


Asunto(s)
Hipercolesterolemia/dietoterapia , Lípidos/sangre , Proteínas de Soja/uso terapéutico , Yogur , Adulto , Anciano , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Cotiledón , Fibras de la Dieta/administración & dosificación , Método Doble Ciego , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/fisiopatología , Isoflavonas/administración & dosificación , Masculino , Persona de Mediana Edad , Fosfolípidos/administración & dosificación
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