Analysis of "Hybrid Closed Loop Using a Do-It-Yourself Artificial Pancreas System in Adults With Type 1 Diabetes"

In an article in Journal of Diabetes Science and Technology, Nanayakkara and colleagues assessed the glycemic efficacy and safety of AndroidAPS, an open-source automated delivery (AID) system, in a crossover randomized controlled trial. Although the trial included only 20 participants during a relatively short 4-week intervention period, glycemic outcomes attained were similar to commercial AID systems and there were no safety concerns. Validation of open-source AID systems in studies such as this should help address clinician hesitancy regarding these systems, and affirms the role of patient-centered innovation and self-management in diabetes care.

Smokers’ Regrets and the Case for Public Health Paternalism

Paternalist policies in public health often aim to improve people’s well-being by reducing their options, regulating smoking offering a prime example. The well-being challenge is to show that people really are better off for having their options reduced. The distribution challenge is to show how the policies are justified since they produce losers as well as winners. If we start from these challenges, we can understand the importance of the empirical evidence that a very high proportion of smokers regret smoking. In short, it is important that they regret it and important that the proportion is so high. This paper explains how, philosophically, regret can relate to well-being and it considers some of the strengths and weakness in the empirical research that the explanation brings out. The regret case for regulating smoking is indeed strong, although not as strong as the empirical researchers think. It is much weaker for paternalistic intervention in other public health problems, such as obesity and binge drinking.

Plasma levels of soluble VEGF receptor isoforms, circulating pterins and VEGF system SNPs as prognostic biomarkers in patients with acute coronary syndromes

Background

Development of collateral circulation in coronary artery disease is cardio-protective. A key process in forming new blood vessels is attraction to occluded arteries of monocytes with their subsequent activation as macrophages. In patients from a prospectively recruited post-acute coronary syndromes cohort we investigated the prognostic performance of three products of activated macrophages, soluble vascular endothelial growth factor (VEGF) receptors (sFlt-1 and sKDR) and pterins, alongside genetic variants in VEGF receptor genes, VEGFR-1 and VEGFR-2.

Methods

Baseline levels of sFlt-1 (VEGFR1), sKDR (VEGFR2) and pterins were measured in plasma samples from subgroups (n = 513; 211; 144, respectively) of the Coronary Disease Cohort Study (CDCS, n = 2067). DNA samples from the cohort were genotyped for polymorphisms from the VEGFR-1 gene SNPs (rs748252 n = 2027, rs9513070 n = 2048) and VEGFR-2 gene SNPs (rs2071559 n = 2050, rs2305948 n = 2066, rs1870377 n = 2042).

Results

At baseline, levels of sFlt-1 were significantly correlated with age, alcohol consumption, NTproBNP, BNP and other covariates relevant to cardiovascular pathophysiology. Total neopterin levels were associated with alcohol consumption at baseline. 7,8 dihydroneopterin was associated with BMI. The A allele of VEGFR-2 variant rs1870377 was associated with higher plasma sFlt-1 and lower levels of sKDR at baseline. Baseline plasma sFlt-1 was univariately associated with all cause mortality with (p < 0.001) and in a Cox’s proportional hazards regression model sFlt-1 and pterins were both associated with mortality independent of established predictors (p < 0.027).

Conclusions

sFlt-1 and pterins may have potential as prognostic biomarkers in acute coronary syndromes patients. Genetic markers from VEGF system genes warrant further investigation as markers of levels of VEGF system components in these patients.

Trial registration

Australian New Zealand Clinical Trials Registry. ACTRN12605000431628. 16 September 2005, Retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0894-1) contains supplementary material, which is available to authorized users.

Managing complex respiratory patients in the community: an evaluation of a pilot integrated respiratory care service

Introduction

In the UK, there is significant variation in respiratory care and outcomes. An integrated approach to the management of high-risk respiratory patients, incorporating specialist and primary care teams' expertise, is the basis for new integrated respiratory services designed to reduce this variation; however, this model needs evaluating.

Methods

To evaluate an integrated service managing high-risk respiratory patients, electronic searches for patients with asthma and chronic obstructive pulmonary disease at risk of poor outcomes were performed in two general practitioner (GP) practices in a local service-development initiative. Patients were reviewed at joint clinics by primary and secondary care professionals. GPs also nominated patients for inclusion. Reviews were delivered to best standards of care including assessments of diagnosis, control, spirometry, self-management, education, medication, inhaler technique and smoking cessation support. Follow-up of routine clinical data collected at 9-months postclinic were compared with seasonally matched 9-months prior to integrated review.

Results

82 patients were identified, 55 attended. 13 (23.6%) had their primary diagnosis changed. In comparison with the seasonally adjusted baseline period, in the 9-month follow-up there was an increase in inhaled corticosteroid prescriptions of 23.3%, a reduction in short-acting β₂-agonist prescription of 33.3%, a reduction in acute respiratory exacerbations of 67.6%, in unscheduled GP surgery visits of 53.3% and acute respiratory hospital admissions reduced from 3 to 0. Only 4 patients (7.3%) required referral to secondary care. Health economic evaluation showed respiratory-related costs per patient reduced by £231.86.

Conclusions

Patients with respiratory disease in this region at risk of suboptimal outcomes identified proactively and managed by an integrated team improved outcomes without the need for hospital referral.

Should Children Be Given Priority in Kidney Allocation?

Kidneys for transplantation are scarce, and many countries give priority to children in allocating them. This paper explains and criticizes the paediatric priority. We set out the relevant ethical principles of allocation, such as utility and severity, and the relevant facts to do with such matters as sensitization and child development. We argue that the facts and principles do not support and sometimes conflict with the priority given to children. We next consider various views on how age or the status of children should affect allocation. Again, these views do not support priority to children in its current form. Since distinctions based on age ought to be positively justified, the failure of all these attempts at justification implies that the priority to children is ethically mistaken. Finally, the paper points to evidence that the paediatric priority reduces the overall supply of kidneys, at least in the United States. Paediatric priority is a real-world policy that seems discriminatory, in some places probably reduces the supply of organs, has no robust official defence, and is unsupported by mainstream ethical principles. Consequently, it should be ended.

Selection into medical school: from tools to domains

BACKGROUND

Most research into the validity of admissions tools focuses on the isolated correlations of individual tools with later outcomes. Instead, looking at how domains of attributes, rather than tools, predict later success is likely to be more generalizable. We aim to produce a blueprint for an admissions scheme that is broadly relevant across institutions.

METHODS

We broke down all measures used for admissions at one medical school into the smallest possible component scores. We grouped these into domains on the basis of a multicollinearity analysis, and conducted a regression analysis to determine the independent validity of each domain to predict outcomes of interest.

RESULTS

We identified four broad domains: logical reasoning and problem solving, understanding people, communication skills, and biomedical science. Each was independently and significantly associated with performance in final medical school examinations.

CONCLUSIONS

We identified two potential errors in the design of admissions schema that can undermine their validity: focusing on tools rather than outcomes, and including a wide range of measures without objectively evaluating the independent contribution of each. Both could be avoided by following a process of programmatic assessment for selection.

Influenza A Virus Challenge Models in Cynomolgus Macaques Using the Authentic Inhaled Aerosol and Intra-Nasal Routes of Infection

Non-human primates are the animals closest to humans for use in influenza A virus challenge studies, in terms of their phylogenetic relatedness, physiology and immune systems. Previous studies have shown that cynomolgus macaques (Macaca fascicularis) are permissive for infection with H1N1pdm influenza virus. These studies have typically used combined challenge routes, with the majority being intra-tracheal delivery, and high doses of virus (> 10⁷ infectious units). This paper describes the outcome of novel challenge routes (inhaled aerosol, intra-nasal instillation) and low to moderate doses (10³ to 10⁶ plaque forming units) of H1N1pdm virus in cynomolgus macaques. Evidence of virus replication and sero-conversion were detected in all four challenge groups, although the disease was sub-clinical. Intra-nasal challenge led to an infection confined to the nasal cavity. A low dose (10³ plaque forming units) did not lead to detectable infectious virus shedding, but a 1000-fold higher dose led to virus shedding in all intra-nasal challenged animals. In contrast, aerosol and intra-tracheal challenge routes led to infections throughout the respiratory tract, although shedding from the nasal cavity was less reproducible between animals compared to the high-dose intra-nasal challenge group. Intra-tracheal and aerosol challenges induced a transient lymphopaenia, similar to that observed in influenza-infected humans, and greater virus-specific cellular immune responses in the blood were observed in these groups in comparison to the intra-nasal challenge groups. Activation of lung macrophages and innate immune response genes was detected at days 5 to 7 post-challenge. The kinetics of infection, both virological and immunological, were broadly in line with human influenza A virus infections. These more authentic infection models will be valuable in the determination of anti-influenza efficacy of novel entities against less severe (and thus more common) influenza infections.

Preparation courses for a medical admissions test: effectiveness contrasts with opinion

OBJECTIVES

The Undergraduate Medicine and Health Sciences Admissions Test (UMAT) is used to rank applicants for admission to many medical schools. This study aimed to determine the effects of preparation courses on UMAT performance and on students' perceptions of their performance.

METHODS

We asked students who sat the UMAT twice across two consecutive years to complete an online survey. The survey was administered in 2010 and 2011 to gather information on preparation activities, costs of preparation activities and students' opinions regarding their expected performance. Survey responses were compared with student scores on the second taking of the UMAT, adjusted for prior UMAT scores and university performance.

RESULTS

The study (cohort: n = 263) was sufficiently powered to investigate two forms of preparation: courses offered by MedEntry (a UMAT preparation provider), and tutoring offered by the students' halls of residence. Neither was found to significantly affect UMAT score (p = 0.09 for MedEntry courses; p = 0.50 for halls of residence tutoring). There was no relationship between total time or money spent preparing and UMAT performance. However, students taking MedEntry courses and students spending more money on UMAT preparation were more likely to predict an improved score (p < 0.001 for both). A total of 85% of students improved their score on the second sitting, irrespective of preparation.

CONCLUSIONS

The use of either of two common forms of UMAT preparation does not translate to an improvement in UMAT score. However, in accordance with confirmation bias theory, the association between money spent on preparatory courses and self-assessed predicted score suggests that students' belief in the effectiveness of such courses may be confounded by their financial outlay.

Contribution of FcRn binding to intestinal uptake of IgG in suckling rat pups and human FcRn-transgenic mice

Immunoglobulin G (IgG) is transcytosed across intestinal epithelial cells of suckling mammals by the neonatal Fc receptor (FcRn); however, the contribution of FcRn vs. FcRn-independent uptake to serum IgG levels had not been determined in either rat pups or human (h)FcRn-expressing mice (Tg276 and Tg32). In isoflurane-anesthetized rodents, serum levels were determined after regional intestinal delivery of human monoclonal antibodies (hIgG) with either wild-type (WT) Fc sequences or variants engineered for different FcRn binding affinities. Detection of full-length hIgG was by immunoassay; intestinal hFcRn and hIgG localization was by immunocytochemistry. High (μg/ml) serum levels of hIgG were detected after proximal intestinal delivery (0.1-10 mg/kg) in 2-wk-old rats. Human FcRn was visualized in epithelial cells of Tg276 mice, but low serum hIgG levels (<10 ng/ml) were obtained. In rat pups, intraintestinal hIgG1 WT administration resulted in dose-related and saturable uptake, whereas uptake of a low FcRn-binding affinity variant was nonsaturable. There were no differences in hIgG levels from systemic and hepatic portal vein serum samples, and intense hIgG immunostaining was noted in villi enterocytes and within lymphatic lacteal-like vessels. This study demonstrated that FcRn-mediated uptake in rat pups accounted for ~80% of serum hIgG levels and that IgG enters the circulation via the lymph and not the hepatic portal vein. The remaining uptake though the immature intestine is nonreceptor mediated. Intestinal epithelial cell hFcRn expression occurred in Tg276 mice, but receptor-mediated transport of IgG was not observed. The suckling rat pup intestine is a mechanistic model of FcRn-IgG-mediated transcytosis.

Racist organ donors and saving lives

This paper considers what should be done about offers of organs for transplant that come with racist strings attached. Saving lives or improving their quality seem powerful reasons to accept the offer. Fairness, justice, and rejecting racism seem like powerful reasons against. This paper argues that conditional allocation should occur when it would provide access to organs for at least one person without costing others their access to organs. The bulk of the paper concentrates on defending this claim against these objections: (i) that the good that might come about through conditional allocation does so through wrongful complicity in the racist's wrongdoing; (ii) that conditional allocation symbolizes support for racism; and (iii) that conditional allocation is unjust or unfair and is, for that reason, impermissible. The final section, on conditional allocation as a policy, considers the speculative possibility that conditional allocation would reduce access to organs for some, but it argues that, even then, conditional allocation could be justified.

Discal attachments of the human temporomandibular joint

BACKGROUND

Despite its clinical significance, the anatomy of the human temporomandibular joint (TMJ) and its relationship to the lateral pterygoid muscle remains poorly described and often misrepresented in standard texts. The aim of this study was to describe how the anterior and posterior attachments of the TMJ disc vary between lateral, central and medial regions of the joint.

METHODS

Ten left TMJs were removed en bloc from cadavers and serial sections were made at 3-4mm intervals. Observations were made to ascertain the anterior and posterior attachments of the disc and the joint structures were traced from standardized photographs.

RESULTS

Laterally, the capsule and lateral discal ligament merged prior to their attachment at the condylar pole. Medially, muscle fibres, capsule and the disc converged on the medial pole of the condyle. There was no evidence that fibres of the upper head of the lateral pterygoid muscle inserted directly into the disc. The upper head inserted into the condyle either directly at the pterygoid fovea or via a central tendon or indirectly via the capsule. Posteriorly, the superior part of the posterior attachment of the disc attached to the cartilaginous meatus and tympanic part of the temporal bone. The inferior part of the posterior attachment of the disc attached to the posterior surface of the condyle. In four joints, this attachment was folded beneath the posterior band of the disc, creating a wedge-shaped flap that ran medio-laterally.

CONCLUSION

This study is in broad agreement with other anatomical TMJ studies but there are two main points of difference. Firstly, a true muscle insertion of the superior head of the lateral pterygoid muscle to the disc was not observed. Secondly, a wedge-shaped flap of retrodiscal tissue was identified between the condyle and the disc.

Individual and family consent to organ and tissue donation: is the current position coherent?

The current position on the deceased's consent and the family's consent to organ and tissue donation from the dead is a double veto-each has the power to withhold and override the other's desire to donate. This paper raises, and to some extent answers, questions about the coherence of the double veto. It can be coherently defended in two ways: if it has the best effects and if the deceased has only negative rights of veto. Whether the double veto has better effects than other policies requires empirical investigation, which is not undertaken here. As for rights, the paper shows that it is entirely possible that individuals have a negative right of veto but no positive right to compel acceptance of their offers. Thus if intensivists and transplant teams turn down the deceased's offer, they do not thereby violate the deceased's right. This leaves it open whether non-rights based reasons-such as avoiding bad publicity or distress -require intensivists and transplant teams to turn down or accept the deceased's offer. This, however, is beyond the scope of this paper. The current position may or may not be wrong, but it is at least coherent.

What's not wrong with conditional organ donation?

In a well known British case, the relatives of a dead man consented to the use of his organs for transplant on the condition that they were transplanted only into white people. The British government condemned the acceptance of racist offers and the panel they set up to report on the case condemned all conditional offers of donation. The panel appealed to a principle of altruism and meeting the greatest need. This paper criticises their reasoning. The panel's argument does not show that conditional donation is always wrong and anyway overlooks a crucial distinction between making an offer and accepting it. But even the most charitable reinterpretation of the panel's argument does not reject selective acceptance of conditional offers. The panel's reasoning has no merit.

Last rights: the ethics of research on the dead

People have strong views about being the subjects of research after their deaths. Should these views be given any weight and, if so, how much? How could we find out what the views are and what should we do if we cannot? This paper defends the idea of posthumous interests and discusses the significance of those interests for research ethics. It argues that we can be guided by a symmetry between the interests of living and dead people and uses posthumous privacy as an example. It also claims that the weight of those interests might not decline even over long periods of time. The arguments have important implications for the ethics of (amongst others) biomedical, archaeological, anthropological, historical, and sociological research.

Parental consent and the use of dead children's bodies

It has recently become known that, in Liverpool and elsewhere, parts of children's bodies were taken postmortem and used for research without the parents being told. But should parental consent be sought before using children's corpses for medical purposes? This paper presents the view that parental consent is overrated. Arguments are rejected for consent from dead children's interests, property rights, family autonomy, and religious freedom. The only direct reason to get parental consent is to avoid distressing the parents, which carries implications for the consent process, secret harvesting of body parts, and the weight to be given to parental feelings.

Research, informed consent, and the limits of disclosure

According to this paper, respect for informed consent implies that subjects should often be told a good deal more than ethical guidelines explicitly or implicitly require. Unless subjects are informed of the researchers' personal characteristics, views, and sponsors whenever they would be likely to consider them significant, their autonomy is being overridden. However, overriding subjects' autonomy is sometimes required by the interests of researchers in not being discriminated against or suffering intrusions into their privacy. This paper resolves the conflict between informed consent and the interests of researchers by recommending that (i) subjects generally should be told of the personal characteristics of researchers when relevant as part of the researchers' job and (ii) that subjects should be told of researchers' views when conceptually connected to the research and (iii) that subjects should almost always be told about sponsorship. While the paper explicitly limits the role of informed consent, these recommendations go significantly beyond most guidelines in their requirements about what information should be disclosed.

A method for protrusive mandibular force measurement in children

With this new method, protrusive mandibular force was studied in a homogeneous group of 69 children with similar occlusions. Maximum protrusive force ranged from 18.5 to 160 N (mean +/- SD = 81.3+/-31.6 N). Maximum protrusive force was significantly higher in males (90.7+/-30.2 N) than females (66.6+/-28.6 N) while fatigue time was not significantly different between the two groups (70.6+/-38.5 s for males and 65.1+/-33.6 s for females). Although protrusive force was stable in each session, it varied considerably between different experimental days within the same individual. No statistically significant correlation was found between maximum protrusive force and age, skeletal maturity, height, weight, overjet, maxillomandibular relation, facial height, facial widths or facial proportions.

A histologic study of retrodiscal tissues of the human temporomandibular joint in the open and closed position

Specialized roles for the different components of the retrodiscal tissues have been previously postulated. This study compared the histologic features of the retrodiscal tissues of temporomandibular joints, taken from human cadavers, in the open and closed position; it was concluded that the primary role of these components was to provide a volumetric compensatory mechanism for pressure equilibration. This mechanism was still active in joints that demonstrated disc displacement and degenerative changes. Elastin was found in the upper and lower strata of the retrodiscal tissues, as well as in the central zone. The concept of an elastic upper stratum that has a recoil mechanism to control disc movement was not supported by this study, as the upper stratum was folded on itself in the closed position and only became stretched near maximal opening.

Silent periods in dysfunction patients: a preliminary study using a novel approach

Strong peri-oral stimulation is known to elicit a transient inhibition in the activity of the jaw-closing muscles. Several reports have claimed that this 'silent period' (SP) is prolonged in patients with temporomandibular joint dysfunction syndromes. In the present preliminary study, the biphasic SP evoked by electrical lip stimulation was tested in single motor units in the masseter muscles of dysfunction patients. In comparison with normal subjects, the pattern of the SP was different in the patients in that the shorter-latency phase predominated over the later phase, whereas the converse is true for normals.

The recognition of craniomandibular disorders--an evaluation of the most reliable signs and symptoms when screening for CMD

Two hundred and twenty-two patients who had been examined and treated for craniomandibular disorders were re-evaluated using a screening protocol. This protocol was developed from previous studies which had elucidated the most reliable signs and symptoms of craniomandibular disorders. Unilateral signs and symptoms were found to be more common than bilateral signs and symptoms. Dynamic and static pain tests were shown to be decisive in determining the preliminary diagnosis. There was a significant difference in vertical condylar height asymmetry between those patients diagnosed as having a myogenous and an arthrogenous origin of pain.

A comparison of the masseteric silent period in temporomandibular joint dysfunction and normal human subjects by surface electromyography and single motor-unit recordings

Single electric stimuli were delivered to the lower lip and the reflex effects were monitored in the ipsilateral masseter. Two strengths of stimulus were delivered at two levels of background excitation (defined in terms of the firing frequency of a single motor unit). Although the threshold stimulus intensity required to produce a silent period in the single motor units was the same for the patients with temporomandibular joint dysfunction and normal subjects, there were qualitative differences in the pattern of reflex responses between the two groups. Of the two phases of inhibition elicited by the stimulus, the short-latency inhibitory period was the more prominent and more resistant to changes in the background excitation levels in the dysfunction group. In normal subjects, however this was true of the long-latency inhibition. This difference may be due to the changes in the inputs to one or more of the interneurones linking the afferent limb of the reflex to the masseteric motoneurones.

Limitation of jaw movement by antagonist muscle stiffness during unloading of human jaw closing muscles

The unloading reflex in the jaw closing muscles in man was investigated with a view to correlating the jaw closing movement with the timing of the electrical activity of the agonist and antagonist muscles. When the resistance to the forceful isometric bite was suddenly and unexpectedly withdrawn, the closing movement of the mandible was always arrested before the teeth came together. The rapid arrest of the jaw closing movement was not adequately accounted for by the timing of the inhibition of the jaw closing muscles and reflex excitation of the jaw opening muscles. It was observed that the jaw opening muscles, as well as the jaw closing muscles, were always active during the phase of isometric biting on an object between the teeth. It is therefore concluded that the resulting stiffness of the antagonist muscles is the mechanism which is principally responsible for limiting the jaw closing movement after unloading of the agonist muscles.

Isolation of glycophorin with deoxycholate

In a previous communication we reported that human erythrocyte glycophorin prepared by the lithium diiodosalicylate phenol procedure contains approximately 10 mol of lithium diiodosalicylate per mol of glycophorin, and further we showed that this bound lithium diiodosalicylate is difficult to remove by detergents or organic solvents (Romans, A.Y. and Segrest, J.P. (1978) Biochim. Biophys. Acta 511, 297-301). In the present communication we report an alternative purification procedure for glycophorin in which sodium deoxycholate is substituted for lithium diiodosalicylate; the sodium deoxycholate is subsequently removed by gel filtration. Utilizing this procedure, 25-30 mg glycophorin are obtained per gram of lyophilized erythrocyte ghosts. The glycophorin prepared by the sodium deoxycholate procedure, after a single gel filtration step, contains less than 1 mol of sodium deoxycholate per mol glycophorin and is colorless compared with glycophorin prepared by the lithium diiodosalicylate procedure, which has a distint reddish-brown cast.