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1.
Anal Bioanal Chem ; 414(1): 351-366, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34435207

RESUMO

An interlaboratory comparison study was conducted by the Vitamin D Standardization Program (VDSP) to assess the performance of ligand binding assays (Part 2) for the determination of serum total 25-hydroxyvitamin D [25(OH)D]. Fifty single-donor samples were assigned target values for concentrations of 25-hydroxyvitamin D2 [25(OH)D2], 25-hydroxyvitamin D3 [25(OH)D3], 3-epi-25-hydroxyvitamin D3 [3-epi-25(OH)D3], and 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3] using isotope dilution liquid chromatography-tandem mass spectrometry (ID LC-MS/MS). VDSP Intercomparison Study 2 Part 2 includes results from 17 laboratories using 32 ligand binding assays. Assay performance was evaluated using mean % bias compared to the assigned target values and using linear regression analysis of the test assay mean results and the target values. Only 50% of the ligand binding assays achieved the VDSP criterion of mean % bias ≤ |± 5%|. For the 13 unique ligand binding assays evaluated in this study, only 4 assays were consistently within ± 5% mean bias and 4 assays were consistently outside ± 5% mean bias regardless of the laboratory performing the assay. Based on multivariable regression analysis using the concentrations of individual vitamin D metabolites in the 50 single-donor samples, most assays underestimate 25(OH)D2 and several assays (Abbott, bioMérieux, DiaSorin, IDS-EIA, and IDS-iSYS) may have cross-reactivity from 24R,25(OH)2D3. The results of this interlaboratory study represent the most comprehensive comparison of 25(OH)D ligand binding assays published to date and is the only study to assess the impact of 24R,25(OH)2D3 content using results from a reference measurement procedure.


Assuntos
Espectrometria de Massas em Tandem , Vitamina D , 25-Hidroxivitamina D 2 , Cromatografia Líquida , Ligantes , Padrões de Referência , Vitamina D/análogos & derivados
2.
Anal Bioanal Chem ; 414(2): 1015-1028, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34750644

RESUMO

The Vitamin D External Quality Assessment Scheme (DEQAS) distributes human serum samples four times per year to over 1000 participants worldwide for the determination of total serum 25-hydroxyvitamin D [25(OH)D)]. These samples are stored at -40 °C prior to distribution and the participants are instructed to store the samples frozen at -20 °C or lower after receipt; however, the samples are shipped to participants at ambient conditions (i.e., no temperature control). To address the question of whether shipment at ambient conditions is sufficient for reliable performance of various 25(OH)D assays, the equivalence of DEQAS human serum samples shipped under frozen and ambient conditions was assessed. As part of a Vitamin D Standardization Program (VDSP) commutability study, two sets of the same nine DEQAS samples were shipped to participants at ambient temperature and frozen on dry ice. Twenty-eight laboratories participated in this study and provided 34 sets of results for the measurement of 25(OH)D using 20 ligand binding assays and 14 liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. Equivalence of the assay response for the frozen versus ambient DEQAS samples for each assay was evaluated using multi-level modeling, paired t-tests including a false discovery rate (FDR) approach, and ordinary least squares linear regression analysis of frozen versus ambient results. Using the paired t-test and confirmed by FDR testing, differences in the results for the ambient and frozen samples were found to be statistically significant at p < 0.05 for four assays (DiaSorin, DIAsource, Siemens, and SNIBE prototype). For all 14 LC-MS/MS assays, the differences in the results for the ambient- and frozen-shipped samples were not found to be significant at p < 0.05 indicating that these analytes were stable during shipment at ambient conditions. Even though assay results have been shown to vary considerably among different 25(OH)D assays in other studies, the results of this study also indicate that sample handling/transport conditions may influence 25(OH)D assay response for several assays.


Assuntos
Congelamento , Vitamina D/análogos & derivados , Vitamina D/sangue , Cromatografia Líquida/métodos , Humanos , Espectrometria de Massas em Tandem/métodos
3.
Anal Bioanal Chem ; 413(20): 5067-5084, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34184102

RESUMO

An interlaboratory study was conducted through the Vitamin D Standardization Program (VDSP) to assess commutability of Standard Reference Materials® (SRMs) and proficiency testing/external quality assessment (PT/EQA) samples for determination of serum total 25-hydroxyvitamin D [25(OH)D] using ligand binding assays and liquid chromatography-tandem mass spectrometry (LC-MS/MS). A set of 50 single-donor serum samples were assigned target values for 25-hydroxyvitamin D2 [25(OH)D2] and 25-hydroxyvitamin D3 [25(OH)D3] using reference measurement procedures (RMPs). SRM and PT/EQA samples evaluated included SRM 972a (four levels), SRM 2973, six College of American Pathologists (CAP) Accuracy-Based Vitamin D (ABVD) samples, and nine Vitamin D External Quality Assessment Scheme (DEQAS) samples. Results were received from 28 different laboratories using 20 ligand binding assays and 14 LC-MS/MS methods. Using the test assay results for total serum 25(OH)D (i.e., the sum of 25(OH)D2 and 25(OH)D3) determined for the single-donor samples and the RMP target values, the linear regression and 95% prediction intervals (PIs) were calculated. Using a subset of 42 samples that had concentrations of 25(OH)D2 below 30 nmol/L, one or more of the SRM and PT/EQA samples with high concentrations of 25(OH)D2 were deemed non-commutable using 5 of 11 unique ligand binding assays. SRM 972a (level 4), which has high exogenous concentration of 3-epi-25(OH)D3, was deemed non-commutable for 50% of the LC-MS/MS assays.


Assuntos
Sociedades Médicas/normas , Vitamina D/análogos & derivados , Vitamina D/química , Humanos , Padrões de Referência , Manejo de Espécimes , Vitamina D/sangue
4.
Addict Biol ; 25(6): e12832, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31736187

RESUMO

Chronic alcohol abuse and depressive symptoms are both associated with peripheral cytokine changes. Despite this, cytokine adaptations have not been assessed in co-morbid populations or prospectively as predictors of relapse. We examine cytokine responses to stress in alcohol-dependent individuals and social drinkers, both with and without subclinical depression. We also examine the potential link between cytokine adaptations in response to stress and prospective alcohol relapse risk. Thirty-three, alcohol-dependent individuals (21 with and 12 without high depressive symptoms) and 37 controls (16 with and 21 without high depressive symptoms) were exposed to two 5-minute personalized guided imagery conditions (stress and neutral) across consecutive days in a randomized and counterbalanced order. Alcohol craving and serum measures of tumor necrosis factor alpha (TNFα), tumor necrosis factor receptor 1 (TNFR1), interleukin-6 (IL-6), and interleukin-1 receptor antagonist (IL-1ra) were collected prior to and following imagery exposure. Following treatment discharge, follow-up interviews were conducted over 90 days to assess relapse. Dampened IL-1ra and IL-6 in response to stress was observed as a function of alcohol dependence and not moderated by depressive symptoms. Lower levels of IL-6 following stress also predicted greater drinking days following treatment. Conversely, high depressive symptomatology was associated solely with pro-inflammatory adaptations. Stress-related suppression of TNFα predicted drinking severity only in alcohol-dependent individuals with subclinical depression, and suppressed TNFR1 following stress was only seen in individuals with subclinical depression. Stress-induced suppression of pro-inflammatory TNF markers may indicate a risk factor for alcohol-dependent individuals with co-occurring depressive symptoms.


Assuntos
Alcoolismo/imunologia , Alcoolismo/terapia , Fissura , Citocinas/sangue , Depressão/terapia , Imagens, Psicoterapia , Estresse Psicológico/terapia , Adulto , Alcoolismo/complicações , Depressão/complicações , Feminino , Humanos , Masculino , Estresse Psicológico/complicações
5.
J Biol Chem ; 293(39): 15055-15069, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-30082316

RESUMO

Antibody-mediated blockade of cluster of differentiation 47 (CD47)-thrombospondin-1 (TSP-1) interactions blocks osteoclast formation in vitro and attenuates parathyroid hormone (PTH)-induced hypercalcemia in vivo in mice. Hypercalcemia in this model reflects increased bone resorption. TSP-1 has two cell-associated binding partners, CD47 and CD36. The roles of these two molecules in mediating the effects of TSP1 in osteoclasts are unclear. Osteoclast formation was attenuated but not absent when preosteoclasts isolated from CD47-/- mice were cocultured with WT osteoblasts. Suppressing CD36 in osteoclast progenitors also attenuated osteoclast formation. The hypercalcemic response to a PTH infusion was blunted in CD47-/-/CD36-/- (double knockout (DKO)) female mice but not CD47-/- mice or CD36-/- animals, supporting a role for both CD47 and CD36 in mediating this effect. Consistent with this, DKO osteoclasts had impaired resorptive activity when analyzed in vitro Inhibition of nitric oxide (NO) signaling is known to promote osteoclastogenesis, and TSP-1 suppresses NO production and signaling. An anti-TSP-1 antibody increased NO production in osteoclasts, and the inhibitory effect of anti-TSP-1 on osteoclastogenesis was completely rescued by l-nitroarginine methyl ester (l-NAME), a competitive NO synthase inhibitor. Supportive of an important role for CD36 in mediating the pro-osteoclastogenic effects of TSP-1, engaging CD36 with a synthetic agonist, p907, suppressed NO production in anti-TSP-1-treated cultures, allowing osteoclast maturation to occur. These results establish that CD36 and CD47 both participate in mediating the actions of TSP-1 in osteoclasts and establish a physiologically relevant cross-talk in bone tissue between these two molecules.


Assuntos
Antígenos CD36/genética , Antígeno CD47/genética , Óxido Nítrico/biossíntese , Trombospondina 1/genética , Animais , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Antígenos CD36/química , Antígeno CD47/química , Feminino , Hipercalcemia/genética , Hipercalcemia/patologia , Proteínas de Membrana/química , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/química , Osteoclastos/química , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/genética , Hormônio Paratireóideo/química , Hormônio Paratireóideo/genética , Detecção de Sinal Psicológico , Transdução de Sinais/efeitos dos fármacos , Trombospondina 1/química
6.
Calcif Tissue Int ; 102(6): 666-670, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29383408

RESUMO

Previous work has demonstrated that a single subcutaneous dose of salmon calcitonin leads to a transient decline in circulating levels of FGF23 in patients with X-linked hypophosphatemia (XLH). Since the calcitonin receptor is expressed on osteocytes, this raises the possibility that interdicting signals through that receptor could modulate circulating levels of FGF23 in XLH. In the present study, 21 subjects with XLH were randomly assigned to receive either placebo nasal spray or 400 IU of nasal salmon calcitonin daily for three months. On the first and last day of the study, serial measurements of FGF23, 1,25-dihydroxyvitamin D, and TmP/GFR were made over 27 h. At the beginning of Visit 2 (the first day of month 2) and the beginning of Visit 3 (the first day of month 3), single, first-morning, fasting measurements of these same parameters were made before the next administered dose of study drug. Following the initial or final dose of study drug, there were no differences in area under the curve, based on treatment assignment, for the three principal outcome variables. Similarly, there were no differences in the fasting measures taken at the beginning of Visit 2 or Visit 3 compared to the fasting values on either day 2 of Visit 1 or the fasting values on day 2 of Visit 4. There were also no significant changes over time in serum phosphorus, serum calcium, circulating levels of PTH, CTx, or P1NP. The reasons why nasal salmon calcitonin did not recapitulate the findings with subcutaneously administered drug may relate to the kinetics of drug delivery, the bioavailability of drug or peak drug dose achieved. It remains possible, however, that other means of altering calcitonin receptor signaling may still provide an opportunity for regulating FGF23 production.


Assuntos
Calcitonina/uso terapêutico , Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Fatores de Crescimento de Fibroblastos/efeitos dos fármacos , Resultado do Tratamento , Adulto , Calcitonina/administração & dosagem , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fosfatos/metabolismo , Fósforo/farmacologia
7.
Ann Surg ; 266(6): 1075-1083, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-27611607

RESUMO

OBJECTIVE: We asked if leptin and its cognate receptor were present in normal and diseased parathyroid glands, and if so, whether they had any functional effects on parathyroid hormone (PTH) secretion in parathyroid neoplasms. BACKGROUND: The parathyroid glands acting through PTH play a critical role in the regulation of serum calcium. Based on leptin's recently discovered role in bone metabolism, we hypothesized these glands were the sites of a functional interaction between these 2 hormones. METHODS: From July 2010 to July 2011, 96 patients were enrolled in a prospective study of leptin and hyperparathyroidism, all of whom were enrolled based on their diagnosis of hyperparathyroidism, and their candidacy for surgical intervention provided informed consent. Immediately after parathyroidectomy, 100 to 300 mg of adenomatous or hyperplastic diseased parathyroid tissue was prepared and processed according to requirements of the following: in situ hybridization, immunohistochemistry, immunofluorescence by conventional and spinning disc confocal microscopy, electron microscopy, parathyroid culture, whole organ explant, and animal model assays. RESULTS: Leptin, leptin receptor (long isoform), and PTH mRNA transcripts and protein were detected in an overlapping fashion in parathyroid chief cells in adenoma and hyperplastic glands, and also in normal parathyroid by in situ hybridization, qRT-PCR, and immunohistochemistry. Confocal microscopy confirmed active exogenous leptin uptake in cultured parathyroid cells. PTH secretion in explants increased in response to leptin and decreased with leptin receptor signaling inhibition by AG490, a JAK2/STAT3 inhibitor. Ob/ob mice injected with mouse leptin exhibited increased PTH levels from baseline. CONCLUSIONS: Taken together, these data suggest that leptin is a functionally active product of the parathyroid glands and stimulates PTH release.


Assuntos
Leptina/metabolismo , Glândulas Paratireoides/metabolismo , Hormônio Paratireóideo/metabolismo , Adenoma/metabolismo , Animais , Células Cultivadas , Humanos , Hiperparatireoidismo/metabolismo , Hiperplasia/metabolismo , Imuno-Histoquímica , Camundongos Knockout , Microscopia Confocal , Microscopia de Fluorescência , Microscopia Imunoeletrônica , Glândulas Paratireoides/patologia , Neoplasias das Paratireoides/metabolismo , Estudos Prospectivos , RNA Mensageiro/metabolismo , Receptores para Leptina/antagonistas & inibidores , Receptores para Leptina/metabolismo
8.
Alcohol Clin Exp Res ; 41(3): 585-595, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28147432

RESUMO

BACKGROUND: Increasing evidence suggests that levels of pro-inflammatory and anti-inflammatory cytokines are dysfunctional in alcohol dependence. Moreover, some initial findings demonstrate that these adaptations in peripheral inflammation may contribute to motivation for alcohol and problem drinking via possible direct effects or the indirect effects of stress responsivity. Importantly, the role of pro-inflammatory and anti-inflammatory cytokines in the progression from healthy to problem drinking is not well understood. The aim of this study was to assess whether alcohol-related peripheral immune system changes affect stress and alcohol cue-induced craving and anxiety and behavioral alcohol motivation and intake in the laboratory among problem drinkers compared with socially drinking controls. METHODS: Twenty-six problem drinkers and 38 moderate, social drinkers participated in a laboratory challenge procedure during which they were exposed to 3 personalized 5-minute imagery conditions (stress [S], relaxing [R], and alcohol cue [C]), followed by the "alcohol taste test" (ATT) as a measure of implicit alcohol motivation and intake, presented across 3 consecutive days, 1 per day in a randomized and counterbalanced order. Measures of tumor necrosis factor-alpha (TNFα), interleukin-6 (IL-6), interleukin-1 receptor antagonist (IL-1ra), alcohol craving, and anxiety were assessed at baseline, immediately following imagery exposure and at discreet beer cue presentation in the ATT. RESULTS: Compared with moderate drinkers, problem drinkers demonstrated tonic attenuation of IL-6 and IL-1ra. In problem drinkers, these changes also accompanied elevated levels of stress- and cue-induced alcohol craving and anxiety and were predictive of provoked alcohol craving, behavioral alcohol motivation and intake, and severity of problem drinking. CONCLUSIONS: Current findings indicate that selective immunosuppression in problem drinkers may play a key role in motivation for alcohol intake.


Assuntos
Consumo de Bebidas Alcoólicas/imunologia , Consumo de Bebidas Alcoólicas/psicologia , Sinais (Psicologia) , Imaginação/fisiologia , Mediadores da Inflamação/imunologia , Motivação/fisiologia , Adulto , Consumo de Bebidas Alcoólicas/sangue , Cerveja , Etanol/administração & dosagem , Feminino , Humanos , Imaginação/efeitos dos fármacos , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Mediadores da Inflamação/sangue , Masculino , Motivação/efeitos dos fármacos , Distribuição Aleatória , Adulto Jovem
9.
J Nutr ; 144(3): 282-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24431325

RESUMO

Increasing dietary protein within a physiologic range stimulates intestinal calcium absorption, but it is not known if specific amino acids or dietary protein as a whole are responsible for this effect. Therefore, we selectively supplemented a low-protein (0.7 g/kg) diet with either the calcium-sensing receptor-activating amino acids (CaSR-AAAs) L-tryptophan, L-phenylalanine, and L-histidine, or the dibasic amino acids (DAAs) L-arginine and L-lysine, to achieve intakes comparable to the content of a high-protein diet (2.1 g/kg) and measured intestinal calcium absorption. Fourteen young women took part in a placebo-controlled, double-blind, crossover feeding trial in which each participant ingested a 6-d low-protein diet supplemented with CaSR-AAAs, DAAs, or methylcellulose capsules (control) after an 11-d adjustment period. All participants ingested all 3 diets in random order. Intestinal calcium absorption was measured between days 5 and 6 using dual-stable calcium isotopes ((42)Ca, (43)Ca, and (44)Ca). There was no difference in calcium absorption between the diet supplemented with CaSR-AAAs (22.9 ± 2.0%) and the control diet (22.3 ± 1.4%) (P = 0.64). However, calcium absorption tended to be greater during the DAA supplementation period (25.2 ± 1.4%) compared with the control diet period (22.3 ± 1.4%) (P < 0.10). Larger and longer clinical trials are needed to clarify the possible benefit of arginine and lysine on calcium absorption.


Assuntos
Diamino Aminoácidos/administração & dosagem , Cálcio da Dieta/urina , Dieta com Restrição de Proteínas , Suplementos Nutricionais , Adulto , Arginina/administração & dosagem , Índice de Massa Corporal , Cálcio da Dieta/farmacocinética , Creatinina/sangue , Estudos Cross-Over , Proteínas Alimentares/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Absorção Intestinal , Lisina/administração & dosagem , Fenilalanina/administração & dosagem , Receptores de Detecção de Cálcio/metabolismo , Triptofano/administração & dosagem , Vitamina D/análogos & derivados , Vitamina D/sangue , Adulto Jovem
10.
J Clin Endocrinol Metab ; 109(3): e1061-e1071, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37930769

RESUMO

CONTEXT: In clinical trials, burosumab ameliorates symptoms of pain, fatigue, and stiffness and improves performance on certain muscle function studies in patients with X-linked hypophosphatemia (XLH). OBJECTIVE: This work aimed to determine if burosumab increases adenosine triphosphate (ATP) synthesis in skeletal muscle of treatment-naive adults with XLH, and if so, whether that correlates with improved muscle function. METHODS: Ten untreated, symptomatic adults with XLH had ATP synthesis rates measured in the right calf using the 31P magnetic resonance spectroscopy saturation transfer technique. Baseline muscle function tests and symptoms of pain, fatigue, stiffness, and lower-extremity joint pain were quantified. All participants were treated with burosumab, 1 mg/kg every 4 weeks for 12 weeks. ATP synthesis rates and muscle function tests were repeated 2 weeks ("peak") and 4 weeks ("trough") after the third dose of burosumab. RESULTS: All symptoms improved with treatment. Performance on the 6-Minute Walk Test (6MWT) and Sit to Stand (STS) tests also improved. Muscle strength and ATP synthesis rates did not change over the 3 months of the study. When individuals whose performances on the 6MWT and STS test were at or better than the median outcome for those tests were compared to those whose outcomes were below the median, no difference was observed in the rate of change in ATP synthesis. Intracellular muscle concentrations of phosphate were normal. CONCLUSION: The improvement in the 6MWT and STS test without changes in muscle strength or ATP synthesis rates suggests that reductions in pain, fatigue, and stiffness may partly explain the improved performance. Intracellular phosphate in skeletal muscle is insulated from hypophosphatemia in XLH.


Assuntos
Anticorpos Monoclonais Humanizados , Anticorpos Monoclonais , Raquitismo Hipofosfatêmico Familiar , Adulto , Humanos , Anticorpos Monoclonais/uso terapêutico , Raquitismo Hipofosfatêmico Familiar/diagnóstico , Trifosfato de Adenosina , Músculo Esquelético , Polifosfatos/uso terapêutico , Dor/tratamento farmacológico , Perna (Membro) , Fadiga/tratamento farmacológico
11.
Gerontologist ; 64(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37067944

RESUMO

BACKGROUND AND OBJECTIVES: Relational caring has the capacity to reduce stigma associated with dementia by shifting the focus from dysfunction and behavior management, to attending to the interdependencies and reciprocities that underpin caring relationships, and making explicit the centrality of relationships to quality care, growth, and quality of life. Education, particularly arts-based approaches, has been identified as a key strategy to decrease stigma. Yet rarely are the arts utilized in educational initiatives, and particularly so in community care settings. With an interest in redressing this, our team evaluated the impact of a Canadian filmed research-based drama-Cracked: new light on dementia-about stigma associated with people living with dementia and their families. RESEARCH DESIGN AND METHODS: We conducted interviews with family carers of people living with dementia and formal care providers affiliated with community-based dementia care, and also the general public at 3 and 8 months postscreening. RESULTS: Our analysis of participants' perceptions/experiences illustrates the effectiveness of Cracked in reducing stigma by demonstrating changes in the understanding of dementia and changes in practice. Our analysis also includes attention to how the film, as a form of cultural production, deepened engagement and facilitated transformation. DISCUSSION AND IMPLICATIONS: Our evaluation of Cracked demonstrates that it is an effective strategy for decreasing the stigma associated with dementia by promoting relational caring. It also importantly contributes to the theoretical literature that supports film-based approaches to stigma reduction.


Assuntos
Demência , Humanos , Canadá , Qualidade de Vida , Cuidadores , Estigma Social
12.
Bone ; 184: 117086, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38552893

RESUMO

PURPOSE: Mitofusin 2 (Mfn2) is one of two mitofusins involved in regulating mitochondrial size, shape and function, including mitophagy, an important cellular mechanism to limit oxidative stress. Reduced expression of Mfn2 has been associated with impaired osteoblast differentiation and function and a reduction in the number of viable osteocytes in bone. We hypothesized that the genetic absence of Mfn2 in these cells would increase their susceptibility to aging-associated metabolic stress, leading to a progressive impairment in skeletal homeostasis over time. METHODS: Mfn2 was selectively deleted in vivo at three different stages of osteoblast lineage commitment by crossing mice in which the Mfn2 gene was floxed with transgenic mice expressing Cre under the control of the promoter for Osterix (OSX), collagen1a1, or DMP1 (Dentin Matrix Acidic Phosphoprotein 1). RESULTS: Mice in which Mfn2 was deleted using DMP1-cre demonstrated a progressive and dramatic decline in bone mineral density (BMD) beginning at 10 weeks of age (n = 5 for each sex and each genotype from age 10 to 20 weeks). By 15 weeks, there was evidence for a functional decline in muscle performance as assessed using a rotarod apparatus (n = 3; 2 males/ 1 female for each genotype), accompanied by a decline in lean body mass. A marked reduction in trabecular bone mass was evident on bone histomorphometry, and biomechanical testing at 25 weeks (k/o: 2 male/1 female, control 2 male/2 female) revealed severely impaired femur strength. Extensive regional myofiber atrophy and degeneration was observed on skeletal muscle histology. Electron microscopy showed progressive disruption of cellular architecture, with disorganized sarcomeres and a bloated mitochondrial reticulum. There was also evidence of neurodegeneration within the ventral horn and roots of the lumbar spinal cord, which was accompanied by myelin loss and myofiber atrophy. Deletion of Mfn2 using OSX-cre or Col1a1-cre did not result in a musculoskeletal phenotype. Where possible, male and female animals were analyzed separately, but small numbers of animals in each group limited statistical power. For other outcomes, where sex was not considered, small sample sizes might still limit the strength of the observation. CONCLUSION: Despite known functional overlap of Mfn1 and Mfn2 in some tissues, and their co-expression in bone, muscle and spinal cord, deletion of Mfn2 using the 8 kB DMP1 promoter uncovered an important non-redundant role for Mfn2 in maintaining the neuromuscular/bone axis.


Assuntos
Densidade Óssea , GTP Fosfo-Hidrolases , Animais , Feminino , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética , Masculino , Camundongos , Densidade Óssea/genética , Densidade Óssea/fisiologia , Camundongos Transgênicos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Osso e Ossos/patologia , Osso e Ossos/metabolismo , Junção Neuromuscular/metabolismo , Junção Neuromuscular/patologia , Osteoblastos/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética
13.
Emerg Nurse ; 21(3): 16-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23888561

RESUMO

Nurses working in emergency departments (EDs) need specialist training to identify and respond appropriately to patients who have experienced domestic abuse (Gibbons 2011). This article describes the development of a domestic abuse nurse specialist role in an ED, a training programme for new ED staff and relevant resources for patients. It also outlines the results of an evaluation of the role and makes recommendations for service development.


Assuntos
Violência Doméstica/prevenção & controle , Enfermagem Forense , Enfermeiros Clínicos , Bases de Dados Factuais , Inglaterra , Enfermagem Forense/educação , Humanos , Enfermeiros Clínicos/educação , Papel do Profissional de Enfermagem , Vigilância da População
14.
Psychopharmacology (Berl) ; 240(1): 101-114, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36445398

RESUMO

RATIONALE: Chronic alcohol intake down-regulates GABAergic transmission and reduces levels of neuroactive steroids. These changes are associated with greater stress dysregulation and high alcohol craving which in turn increases relapse risk. OBJECTIVES: This study tested whether potentiation of the neurosteroid system with pregnenolone (PREG), a precursor to neuroactive steroids and known to increase GABAergic transmission, will normalize chronic alcohol-related stress adaptations in the hypothalamic-pituitary-adrenal (HPA) axis and autonomic responses and reduce alcohol craving to significantly impact relapse risk. METHODS: Forty-three treatment-seeking individuals with alcohol use disorder (AUD) were randomized to placebo (PBO) or supraphysiologic pregnenolone doses of 300 mg or 500 mg treatment using a parallel-between subject design as part of a larger 8-week pilot clinical trial. In week 2, they participated in a 3-day laboratory experiment where on each day they self-administered the assigned study drug in the laboratory and were then exposed to 5-min personalized guided imagery provocation of stress, alcohol, or neutral/relaxing cues, one condition per day on separate days, in a random, counterbalanced order. Repeated assessments of alcohol craving, anxiety, HPA axis, heart rate (HR), systolic (SBP), and diastolic blood pressure (DBP) and serum pregnenolone levels were made on each day. RESULTS: Pregnenolone levels were significantly increased in the PREG groups versus PBO. PREG treatment decreased stress- and alcohol cue- induced craving and dose-specifically reduced stress-induced anxiety in the 300 mg/day group. Both PREG doses compared to PBO also normalized CORT/ACTH and increased stress-induced HR, stress- and cue-induced SBP, and in the 300 mg PREG group cue-induced DBP responses relative to neutral condition. CONCLUSIONS: Findings indicate that pregnenolone decreases stress- and alcohol cue-provoked craving and normalizes HPA axis and autonomic arousal in individuals with AUD, thereby supporting the need for further assessment of pregnenolone in the treatment of AUD.


Assuntos
Alcoolismo , Neuroesteroides , Humanos , Alcoolismo/tratamento farmacológico , Fissura , Sistema Hipotálamo-Hipofisário , Pregnenolona/farmacologia , Neuroesteroides/farmacologia , Sistema Hipófise-Suprarrenal , Ansiedade/tratamento farmacológico , Consumo de Bebidas Alcoólicas , Etanol/farmacologia , Nível de Alerta , Recidiva , Sinais (Psicologia)
15.
J Endocr Soc ; 7(11): bvad116, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37860221

RESUMO

Individuals with X-linked hypophosphatemia (XLH) are at greater risk for being overweight or obese. Whether there are underlying metabolic abnormalities that put patients with XLH at greater risk for excessive weight gain is largely unknown. Lipocalin-2 (LCN2) has recently received attention as a factor regulating energy consumption and specifically is postulated to be anorexigenic and to improve insulin sensitivity. In a retrospective study, circulating levels of LCN2, leptin, and insulin were measured in 32 patients with XLH, ages 2-60 years, all of whom were being treated with burosumab, and 38 control subjects. Control subjects were chosen who were close in age to those with XLH, with a similar number of participants of each sex. Subjects were analyzed in 3 age cohorts, 2-10 years, 11-18 years, and 20-60 years. In all age groups LCN2 levels were lower in the patients with XLH than in controls but when adjusted for weight class (normal, overweight, obese) the differences were not significant. In contrast, serum leptin levels were significantly lower in children with XLH compared to controls in the 2-10 years age cohort. Serum levels of insulin were also significantly lower in the 2-10-year-old children with XLH when compared with controls. We conclude that changes in expression of lipocalin-2 in children and adolescents with XLH is unlikely to contribute to their risk for obesity in adulthood. It is unclear if lower circulating levels of leptin in these children plays a role in the higher prevalence of obesity among adults with XLH.

16.
J Adv Nurs ; 68(9): 1944-55, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22082306

RESUMO

AIM: The aim of this article is to report research findings describing phenomenological shifts, that is, changes in patterns of lived experience, for healthcare professionals who attended a performance of a research-based drama, called I'm Still Here. BACKGROUND: The research drama, based on six studies, was created to help change the ways persons understand, think about and relate with persons living with dementia. METHODS: In 2006-2007, 50 healthcare professionals from various disciplines and eight nursing students participated in this study. Participants were recruited from four Canadian cities in the province of Ontario where focus groups were held before and after engaging in a live performance of I'm Still Here. FINDINGS: Analysis of focus group transcripts showed shifts in patterns of lived experience for the healthcare professional participants as evident in the participants' descriptions. The phenomenological shifts reflected a move from descriptions of 'diminishing humanness to discerning humanness', from 'disengaged care/mundane relating to reflexive relating in the now', and 'terrifying portrayals of loss to awakening to hopeful possibility'. The shifts described herein are supported with examples from the focus group transcripts. CONCLUSIONS: Findings reveal the power of drama as a vibrant and meaningful means of shifting understandings, images and intended actions of healthcare professions which have the potential to affect the lived experiences, relationships and quality of life of persons with dementia.


Assuntos
Atitude do Pessoal de Saúde , Demência , Drama , Empatia , Pessoal de Saúde/educação , Pessoal de Saúde/psicologia , Ensino/métodos , Adaptação Psicológica , Compreensão , Grupos Focais , Humanos , Ontário , Qualidade de Vida/psicologia
17.
Nurs Older People ; 24(10): 14-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23301409

RESUMO

Elder abuse remains a significant problem nationally and globally. Early definitions of abuse, however, oversimplified the phenomena and while the complexity of elder abuse, in nature and scale, has also been growing recently there remains some confusion conceptually and in practice in terms of what is meant by and can be identified as abusive practice. The lack of conceptual clarity is evident across professional and agency boundaries. The authors suggest that a potential way forward is through the development of interprofessional learning as an integral part of education and training in respect of safeguarding older adults. This article highlights a number of complexities in the context of safeguarding and raises areas for further reflection and possible debate.


Assuntos
Educação Profissionalizante/organização & administração , Abuso de Idosos/prevenção & controle , Relações Interinstitucionais , Idoso , Humanos , Terminologia como Assunto , Incerteza , Reino Unido , Populações Vulneráveis
18.
Menopause ; 29(10): 1200-1203, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35969885

RESUMO

OBJECTIVE: The aim of this study was to examine the effect of either conjugated equine estrogen or transdermal estradiol on vitamin D metabolism in postmenopausal women. METHODS: Twenty-five women from the Kronos Early Estrogen Prevention Study who were randomized to conjugated equine estrogen 0.45 mg/d and 20 women who were treated with transdermal estradiol 50 mg/d (patch replaced weekly) were analyzed in the present study. All participants received micronized progesterone for 12 days per month. RESULTS: There was no significant treatment effect on serum total 25-hydroxyvitamin D over 48 months in either study group, and there were no significant differences between treatment arms. In contrast, at 12 months, directly measured free 25-hydroxyvitamin D was significantly higher in the transdermal estradiol group than in the conjugated equine estrogen group. Directly measured free 25-hydroxyvitamin D subsequently increased significantly from 12 to 48 months in both treatment arms. Calculated free 25-hydroxyvitamin D was also significantly higher in the transdermal estradiol group at 36 months. Vitamin D-binding protein decreased significantly in both treatment groups from 12 to 48 months, but at 48 months, least square mean values were no different based on treatment assignment. CONCLUSIONS: Directly measured free 25-hydroxyvitamin D levels, but not serum total 25-hydroxyvitamin D levels, are different within the first 12 months of estrogen replacement depending on the preparation. However, this difference is transient, in that there were no differences at 36 or 48 months. These findings suggest that there may be a short-term benefit to prescribing transdermal estradiol for women who are either vitamin D deficient or vitamin D insufficient.


Assuntos
Estradiol , Estrogênios Conjugados (USP) , Administração Cutânea , Administração Oral , Estradiol/farmacologia , Terapia de Reposição de Estrogênios , Estrogênios/farmacologia , Estrogênios Conjugados (USP)/farmacologia , Feminino , Humanos , Estudos Longitudinais , Pós-Menopausa , Progesterona , Vitamina D/farmacologia , Proteína de Ligação a Vitamina D/farmacologia
19.
Dementia (London) ; 21(1): 61-76, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34166151

RESUMO

AIM: To present findings about experiences of relational caring at an arts-based academy for persons living with dementia. BACKGROUND: There is a compelling call and need for connection and relationships in communities living with dementia. This study shares what is possible when a creative arts-based academy for persons living with dementia grounded in relational inquiry and caring focuses on relationships through the medium of the arts. DESIGN: A qualitative phenomenological methodology (informed by van Manen) was used to answer the research question, "What is it like to experience relational caring at an arts-based academy for persons living with dementia?" We address two research objectives: (1) to explore how relationships are experienced when a relational caring philosophy underpins practice, including arts-based engagements; and (2) to understand the meaning of relationships that bring quality to day-to-day living. METHODS: Twenty-five participants were recruited from the Academy and interviewed in one-to-one in-depth interviews or small groups. Participants included five persons living with dementia, eight family members, four staff, five artists, one personal support worker, and two volunteers. Participants were asked to describe their experiences of relational caring or relationships in the Academy space. FINDINGS: Three thematic patterns emerged, which address the research objectives.Relational caring is experienced when:freedom and fluid engagement inspire a connected spontaneous liveliness;embracing difference invites discovery and generous inclusivity; andmutual affection brings forth trust and genuine expression. CONCLUSIONS: Findings contribute to the growing body of knowledge about both relational caring and arts-based practices that call forth a different ethic of care-one that is relational, inclusive, and intentional. Findings also shed light on what is possible when a relational caring philosophy underpins arts-based practices-everyone thrives.


Assuntos
Arte , Demência , Família , Humanos
20.
Eur J Endocrinol ; 185(2): 333-342, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34128826

RESUMO

OBJECTIVE: GC/DBP effects on response to vitamin D supplementation have not been well-studied. Thus we assessed free and total 25-OHD after vitamin D treatment across the six common GC haplotypes. DESIGN: This double-blind, randomized study compared two vitamin D3 doses in healthy, urban-dwelling 6-month to 10-year-old children at-risk for vitamin D deficiency. Randomization was stratified by GC haplotype. METHODS: Children were randomized to receive 2800 or 7000 International Units of vitamin D3 weekly. 25-OHD and 1,25(OH)2D were sampled at baseline and after 1-6 months of supplementation. RESULTS AND CONCLUSIONS: One hundred ninety-two of 225 enrolled subjects completed the study. After one month, total 25-OHD increased with both doses and were higher with 7000 IU/week (85.5 ± 22.8 nmol/L) compared to 2800 IU/week (76.8 ± 18.0 nmol/L), despite equivalent baseline levels. No further significant increase occurred at 6 months (89.8 ± 35.5 and 74.3 ± 18.3 nmol/L, respectively). Free 25-OHD similarly changed. 25-OHD differed among GC groups at baseline. Although no significant effects of individual GC haplotypes on incremental changes were evident, a trend toward an effect of combined 'at risk' GC alleles on response was evident (P = 0.06). Total 1,25(OH)2D showed modest increases, moreso with the larger dose. In urban-dwelling children at-risk for vitamin D deficiency, 1 month of vitamin D3 2800 IU/week increased 25-OHD across all GC haplotype groups, and somewhat enhanced with 7000 IU/week with no further significant increases after 6 months of supplementation. Free 25-OHD measures offer no monitoring advantage over total 25-OHD.


Assuntos
25-Hidroxivitamina D 2/sangue , Colecalciferol/administração & dosagem , Colecalciferol/sangue , Haplótipos/fisiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/dietoterapia , Criança , Pré-Escolar , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Deficiência de Vitamina D/diagnóstico
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