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The proportion of isolated single beta-cells developing a metabolic, biosynthetic, or secretory response increases with glucose concentration (recruitment). It is unclear whether recruitment persists in situ when beta-cells are coupled. We therefore measured the cytoplasmic free Ca2+ correction ([Ca2+]i) (the triggering signal of glucose-induced insulin secretion) in mouse islet single cells or clusters cultured for 1-2 days. In single cells, the threshold glucose concentration ranged between 6 and 10 mmol/l, at which concentration a maximum of approximately 65% responsive cells was reached. Only 13% of the cells did not respond to glucose plus tolbutamide. The proportion of clusters showing a [Ca2+]i rise increased from approximately 20 to 95% between 6 and 10 mmol/l glucose, indicating that the threshold sensitivity to glucose differs between clusters. Within responsive clusters, 75% of the cells were active at 6 mmol/l glucose and 95-100% at 8-10 mmol/l glucose, indicating that individual cell recruitment is not prominent within clusters; in clusters responding to glucose, all or almost all cells participated in the response. Independently of cell recruitment, glucose gradually augmented the magnitude of the average [Ca2+]i rise in individual cells, whether isolated or associated in clusters. When insulin secretion was measured simultaneously with [Ca2+]i, a good temporal and quantitative correlation was found between both events. However, beta-cell recruitment was maximal at 10 mmol/l glucose, whereas insulin secretion increased up to 15-20 mmol/l glucose. In conclusion, beta-cell recruitment by glucose can occur at the stage of the [Ca2+]i response. However, this type of recruitment is restricted to a narrow range of glucose concentrations, particularly when beta-cell association decreases the heterogeneity of the responses. Glucose-induced insulin secretion by islets, therefore, cannot entirely be ascribed to recruitment of beta-cells to generate a [Ca2+]i response. Modulation of the amplitude of the [Ca2+]i response and of the action of Ca2+ on exocytosis (amplifying actions of glucose) may be more important. [ABSTRACT FROM AUTHOR]

Context: Percutaneous epiphysiodesis (PE) around the knee to reduce predicted excessive final height. Studies until now included small numbers of patients and short follow-up periods., Objective and Design: This Dutch multicentre, long-term, retrospective, follow-up study aimed to assess adult height (AH), complications, knee function and patient satisfaction after PE. The primary hypothesis was that PE around the knee in constitutionally tall boys and girls is an effective treatment for reducing final height with low complication rates and a high level of patient satisfaction., Participants: 77 treated adolescents and 60 comparisons., Intervention: Percutaneous epiphysiodesis., Outcome: AH, complications, knee function, satisfaction., Results: In the PE-treated group, final height was 7.0 cm (±6.3 cm) lower than predicted in boys and 5.9 cm (±3.7 cm) lower than predicted in girls. Short-term complications in file search were seen in 5.1% (three infections, one temporary nerve injury), one requiring reoperation. Long-term complications in file search were seen in 2.6% (axis deformity 1.3%, prominent head of fibula 1.3%). No significant difference in knee function was found between treated cases and comparisons. Satisfaction was high in both the comparison and PE groups; most patients in the PE group recommended PE as the treatment for close relatives with tall stature., Conclusion: PE is safe and effective in children with predicted excessive AH. There was no difference in patient satisfaction between the PE and comparison group. Careful and detailed counselling is needed before embarking on treatment., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Purpose: To describe the early patient-reported outcomes of articular cartilage repair in patients with pain due to grade III or IV articular cartilage defects after prior anterior cruciate ligament (ACL) reconstruction., Methods: Nineteen patients underwent a gel-type autologous chondrocyte implantation (GACI) procedure after ACL reconstruction. Median timeframe between ACL reconstruction and GACI procedure was 52 months (range 16 to 369). The average age at chondrocyte implantation was 35 (standard deviation (SD) eight) years and average cumulative articular cartilage defect size was nine (SD four) square centimeter. Outcome was assessed prior to the GACI procedure and two years after GACI using the International Knee Documentation Committee (IKDC) score and the Knee injury and Osteoarthritis Outcome Score (KOOS)., Results: Two year post-GACI scores showed a statistically significant improvement of IKDC (13, SD 22, p=.02) and KOOS quality of life (18, SD 27, p=.01) compared to the pre-GACI scores. The other KOOS domains did improve, but not statistically significant. Seven (37%) patients underwent reoperation after the GACI., Conclusion: Patients with prior ACL reconstruction and suffering from ongoing pain associated with cartilage defects can benefit from cartilage repair with GACI., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Details on hyponatraemia in the emergency department are limited, especially regarding older patients, a population more susceptible to hyponatraemia and its effects. Our objective was to gain insight into the prevalence, aetiology, treatment and prognosis of clinically relevant hyponatraemia in elderly emergency department patients. The impact of the severity of hyponatraemia on outcome was a secondary objective., Methods: A retrospective cohort study of 1438 internal medicine patients aged &#8805; 65 years presenting to the emergency department between 1 September 2010 and 31 August 2011 was performed. Clinically relevant hyponatraemia was defined as a serum sodium level < 130 mmol÷l. The reference group had a serum sodium level of 130-145 mmol÷l. Hyponatraemia was subdivided into moderate (129-125 mmol÷l), and severe (< 125 mmol÷l)., Results: Ninety-one elderly patients (6.3%) were hyponatraemic at presentation to the emergency department. The main causes were the use of diuretics, hypovolaemia, and the syndrome of inappropriate antidiuretic hormone secretion (57.1%). Hyponatraemia was associated with higher admission rates (93.4 vs. 72.9%) and longer hospital stay (8 vs. 6 days) vs. the reference group. Three-month survival rate in hyponatraemic elderly patients was 74% (95% CI 64-84%) vs. 83% (95% CI 81-85%) in the reference group. Moderate hyponatraemia was associated with an increased risk of death (HR 1.7, 95% CI 1.2-2.4) vs. the reference group after multivariable adjustment for age and comorbidity., Conclusion: Hyponatraemia, a common electrolyte disturbance among elderly internal medicine patients presenting to the emergency department, was associated with higher admission rates, longer hospital stay, and higher mortality rates. In particular, moderate hyponatraemia was a marker of underlying frailty and predictive of mortality.

Objective: To study the association between antenatal exposure to chorioamnionitis and the neonatal response to surfactant., Study Design: Prospective observational cohort of 301 preterm infants of gestational age < or = 32.0 weeks, 146 of whom received surfactant according to standardized criteria. Fraction of inspired oxygen (FiO(2)) requirement (using analysis of variance) and time to extubation (using Kaplan-Meier and Cox regression analyses) were compared between groups based on the presence of histological chorioamnionitis (HC) with or without fetal involvement (HC-, n = 88; HC + F-, n = 25; HC + F+, n = 33) and between infants who developed bronchopulmonary dysplasia (BPD) or died (n = 57) and BPD-free survivors (n = 89). Multiple logistic regression was performed to investigate the association between HC and BPD., Results: Compared with HC- infants, HC + F+ infants had significantly greater FiO(2) requirement and prolonged time to extubation postsurfactant, not accounted for by differences in gestational age and birth weight. Infants with BPD/death had a strikingly similar pattern of increased FiO(2) requirement postsurfactant. Moreover, in infants who received surfactant, HC + F+ status was associated with increased risk for BPD (odds ratio [OR] = 3.40; 95% confidence interval [CI] = 1.02-11.3; P = .047) and for BPD/death (OR = 2.72; 95% CI = 1.00-7.42; P = .049)., Conclusions: An impaired surfactant response was observed in preterm infants with severe chorioamnionitis and may be involved in the association between chorioamnionitis, mechanical ventilation, and the development of BPD.

Individual pancreatic beta-cells are functionally heterogeneous. Their sensitivity to glucose is variable, so that the proportion of active cells increases with the glucose concentration (recruitment). We have investigated whether sulphonylureas also recruit beta-cells, by measuring cytoplasmic Ca(2+) ([Ca(2+)](i)) - the triggering signal of insulin secretion - in single cells and clusters of cells prepared from mouse islets. In 4 mM glucose, the threshold concentration of tolbutamide inducing a [Ca(2+)](i) rise was variable (5 - 50 microM). The proportion of responsive cells and clusters therefore increased with the tolbutamide concentration, to reach a maximum of 90% of the cells and 100% of the clusters. This recruitment occurred faster when the glucose concentration was increased from 4 to 5 mM (EC(50) of approximately 14 and approximately 4 microM tolbutamide respectively). Within responsive clusters little recruitment was observed; when a cluster was active, all or nearly all cells were active probably because of cell coupling. Thus, tolbutamide-induced [Ca(2+)](i) oscillations were synchronous in all cells of each cluster, whereas there was no synchrony between clusters or individual cells. Independently of cell recruitment, tolbutamide gradually augmented the magnitude of the [Ca(2+)](i) rise in single cells and clusters. This increase occurred over a broader range of concentrations than did recruitment (EC(50) of approximately 50 and 25 microM tolbutamide at 4 and 5 mM glucose respectively). Tolbutamide (10 microM) accelerated the recruitment of single cells and clusters brought about by increasing glucose concentrations (range of 3 - 7 mM instead of 4 - 10 mM glucose), and potentiated the amplification of the individual responses that glucose also produced. In conclusion, both metabolic (glucose) and pharmacologic (sulphonylurea) inhibition of K(+)-ATP channels recruits beta-cells to generate a [Ca(2+)](i) response. However, the response is not of an all-or-none type; it increases in amplitude with the concentration of either glucose or tolbutamide.

Background: The growing number of requests for euthanasia or assisted suicide (EAS) makes it imperative for health care institutions, such as nursing homes, to have written guidelines on how to handle requests for EAS. The objective of this study was to determine the prevalence of EAS guidelines in Dutch nursing homes and to analyze the content., Methods: Directors of patient care in 324 Dutch nursing homes were asked, by means of a mailed short list of questions, if they had an institutional guideline on EAS and, if so, to provide a copy. Guidelines were analyzed according to a structured list of items based on current jurisprudence, model documents, and opinions of experts., Results: Of the 324 directors, 313 (97%) responded. In 58% of the nursing homes that responded, there existed written guidelines for EAS. Of those guidelines, 74% concerned EAS; in 26%, EAS was integrated in a guideline on terminal care. Of the guidelines, 165 (90%) were based on the policy that EAS is acceptable under specific conditions, and 18 (10%) banned EAS completely. Of the first-mentioned guidelines, 81% described one or more procedures for in-principle objections. In 65% of these guidelines, all official requirements for prudent practice were described., Conclusions: Despite the rapidly growing number of nursing-home guidelines on EAS and the existence of model documents, there is still considerable variation in the guidelines, and they can be improved in many aspects. A basic prerequisite is that the guidelines include all the official requirements for prudent practice.

Glucose stimulation of pancreatic beta cells induces oscillations of the membrane potential, cytosolic Ca(2+) ([Ca(2+)](i)), and insulin secretion. Each of these events depends on glucose metabolism. Both intrinsic oscillations of metabolism and repetitive activation of mitochondrial dehydrogenases by Ca(2+) have been suggested to be decisive for this oscillatory behavior. Among these dehydrogenases, mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH), the key enzyme of the glycerol phosphate NADH shuttle, is activated by cytosolic [Ca(2+)](i). In the present study, we compared different types of oscillations in beta cells from wild-type and mGPDH(-/-) mice. In clusters of 5-30 islet cells and in intact islets, 15 mM glucose induced an initial drop of [Ca(2+)](i), followed by an increase in three phases: a marked initial rise, a partial decrease with rapid oscillations and eventually large and slow oscillations. These changes, in particular the frequency of the oscillations and the magnitude of the [Ca(2+)] rise, were similar in wild-type and mGPDH(-/-) mice. Glucose-induced electrical activity (oscillations of the membrane potential with bursts of action potentials) was not altered in mGPDH(-/-) beta cells. In single islets from either type of mouse, insulin secretion strictly followed the changes in [Ca(2+)](i) during imposed oscillations induced by pulses of high K(+) or glucose and during the biphasic elevation induced by sustained stimulation with glucose. An imposed and controlled rise of [Ca(2+)](i) in beta cells similarly increased NAD(P)H fluorescence in control and mGDPH(-/-) islets. Inhibition of the malate-aspartate NADH shuttle with aminooxyacetate only had minor effects in control islets but abolished the electrical, [Ca(2+)](i) and secretory responses in mGPDH(-/-) islets. The results show that the two distinct NADH shuttles play an important but at least partially redundant role in glucose-induced insulin secretion. The oscillatory behavior of beta cells does not depend on the functioning of mGPDH and on metabolic oscillations that would be generated by cyclic activation of this enzyme by Ca(2+).

1. The cytoplasmic Ca2+ concentration ([Ca2+]i) was measured in single cells and cell clusters of different sizes prepared from mouse pancreatic islets. 2. During stimulation with 15 mM glucose, 20 % of isolated cells were inert, whereas 80 % showed [Ca2+]i oscillations of variable amplitude, duration and frequency. Spectral analysis identified a major frequency of 0.14 min-1 and a less prominent one of 0.27 min-1. 3. In contrast, practically all clusters (2-50 cells) responded to glucose, and no inert cells were identified within the clusters. As compared to single cells, mean [Ca2+]i was more elevated, [Ca2+]i oscillations were more regular and their major frequency was slightly higher (but reached a plateau at approximately 0.25 min-1). In some cells and clusters, faster oscillations occurred on top of the slow ones, between them or randomly. 4. Image analysis revealed that the regular [Ca2+]i oscillations were well synchronized between all cells of the clusters. Even when the Ca2+ response was irregular, slow and fast [Ca2+]i oscillations induced by glucose were also synchronous in all cells. 5. In contrast, [Ca2+]i oscillations resulting from mobilization of intracellular Ca2+ by acetylcholine were restricted to certain cells only and were not synchronized. 6. Heptanol and 18alpha-glycyrrhetinic acid, two agents widely used to block gap junctions, altered glucose-induced Ca2+ oscillations, but control experiments showed that they also exerted effects other than a selective uncoupling of the cells. 7. The results support theoretical models predicting an increased regularity of glucose-dependent oscillatory events in clusters as compared to isolated islet cells, but contradict the proposal that the frequency of the oscillations increases with the number of coupled cells. Islet cell clusters function better as electrical than biochemical syncytia. This may explain the co-ordination of [Ca2+]i oscillations driven by depolarization-dependent Ca2+ influx during glucose stimulation.