Association Between Ex Vivo Human Ulcerative Colitis Explant Protein Secretion Profiles and Disease Behaviour.

BACKGROUND: The clinical course of ulcerative colitis (UC) is variable. There is an unmet clinical need for biomarkers of UC disease behaviour. We aimed to evaluate the association between ex vivo human UC explant conditioned media (explant-CM) secreted protein profiles and UC disease behaviour. METHODS: UC patients undergoing endoscopy were prospectively recruited. Endoscopic biopsies were collected and explant-CM generated. Association between explant-CM protein secretion profiles and disease progression was evaluated. Disease progression was defined as the requirement for corticosteroid therapy, UC-related hospitalisation, UC-related surgery or the introduction of a new immunomodulatory agent. Association between explant-CM secreted protein profiles and anti-TNF failure status was also evaluated. p values < 0.05 were considered significant in analyses. RESULTS: Twenty-four UC patients were included (age [median, range]) 55 [21-72] years; 50% female. Disease progression during follow-up occurred in twelve (50%) patients. Multivariate analysis, including endoscopic remission status, demonstrated reduced IL-2 secretion to be independently associated with UC disease progression, p = 0.01. In univariate analysis, anti-TNF failure status was associated with significantly increased IL-17A/F (p = 0.015) and IL-12 / IL-23p40 (p = 0.044) concentrations. In multivariate analysis, there was a trend towards an association between IL-17A/F and anti-TNF failure status (p = 0.069); FLT-1 was demonstrated to be independently associated with anti-TNF failure status (p = 0.016). CONCLUSION: Reduced explant-CM secreted IL-2 is associated with UC disease progression. Increased secretion of IL-23 pathway-associated cytokines was observed in anti-TNF failure status consistent with previous reports. Ex vivo human UC explants, generated from endoscopic biopsies, have potential as precision medicine tools in inflammatory bowel disease.

Fixed-effect variance and the estimation of repeatabilities and heritabilities: issues and solutions.

Linear mixed-effects models are frequently used for estimating quantitative genetic parameters, including the heritability, as well as the repeatability, of traits. Heritability acts as a filter that determines how efficiently phenotypic selection translates into evolutionary change, whereas repeatability informs us about the individual consistency of phenotypic traits. As quantities of biological interest, it is important that the denominator, the phenotypic variance in both cases, reflects the amount of phenotypic variance in the relevant ecological setting. The current practice of quantifying heritabilities and repeatabilities from mixed-effects models frequently deprives their denominator of variance explained by fixed effects (often leading to upward bias of heritabilities and repeatabilities), and it has been suggested to omit fixed effects when estimating heritabilities in particular. We advocate an alternative option of fitting models incorporating all relevant effects, while including the variance explained by fixed effects into the estimation of the phenotypic variance. The approach is easily implemented and allows optimizing the estimation of phenotypic variance, for example by the exclusion of variance arising from experimental design effects while still including all biologically relevant sources of variation. We address the estimation and interpretation of heritabilities in situations in which potential covariates are themselves heritable traits of the organism. Furthermore, we discuss complications that arise in generalized and nonlinear mixed models with fixed effects. In these cases, the variance parameters on the data scale depend on the location of the intercept and hence on the scaling of the fixed effects. Integration over the biologically relevant range of fixed effects offers a preferred solution in those situations.

Towards robust evolutionary inference with integral projection models.

Integral projection models (IPMs) are extremely flexible tools for ecological and evolutionary inference. IPMs track the distribution of phenotype in populations through time, using functions describing phenotype-dependent development, inheritance, survival and fecundity. For evolutionary inference, two important features of any model are the ability to (i) characterize relationships among traits (including values of the same traits across ages) within individuals, and (ii) characterize similarity between individuals and their descendants. In IPM analyses, the former depends on regressions of observed trait values at each age on values at the previous age (development functions), and the latter on regressions of offspring values at birth on parent values as adults (inheritance functions). We show analytically that development functions, characterized this way, will typically underestimate covariances of trait values across ages, due to compounding of regression to the mean across projection steps. Similarly, we show that inheritance, characterized this way, is inconsistent with a modern understanding of inheritance, and underestimates the degree to which relatives are phenotypically similar. Additionally, we show that the use of a constant biometric inheritance function, particularly with a constant intercept, is incompatible with evolution. Consequently, current implementations of IPMs will predict little or no phenotypic evolution, purely as artefacts of their construction. We present alternative approaches to constructing development and inheritance functions, based on a quantitative genetic approach, and show analytically and through an empirical example on a population of bighorn sheep how they can potentially recover patterns that are critical to evolutionary inference.

Meta-analysis of magnitudes, differences and variation in evolutionary parameters.

Meta-analysis is increasingly used to synthesize major patterns in the large literatures within ecology and evolution. Meta-analytic methods that do not account for the process of observing data, which we may refer to as 'informal meta-analyses', may have undesirable properties. In some cases, informal meta-analyses may produce results that are unbiased, but do not necessarily make the best possible use of available data. In other cases, unbiased statistical noise in individual reports in the literature can potentially be converted into severe systematic biases in informal meta-analyses. I first present a general description of how failure to account for noise in individual inferences should be expected to lead to biases in some kinds of meta-analysis. In particular, informal meta-analyses of quantities that reflect the dispersion of parameters in nature, for example, the mean absolute value of a quantity, are likely to be generally highly misleading. I then re-analyse three previously published informal meta-analyses, where key inferences were of aspects of the dispersion of values in nature, for example, the mean absolute value of selection gradients. Major biological conclusions in each original informal meta-analysis closely match those that could arise as artefacts due to statistical noise. I present alternative mixed-model-based analyses that are specifically tailored to each situation, but where all analyses may be implemented with widely available open-source software. In each example meta-re-analysis, major conclusions change substantially.

Multivariate selection and intersexual genetic constraints in a wild bird population.

When selection differs between the sexes for traits that are genetically correlated between the sexes, there is potential for the effect of selection in one sex to be altered by indirect selection in the other sex, a situation commonly referred to as intralocus sexual conflict (ISC). While potentially common, ISC has rarely been studied in wild populations. Here, we studied ISC over a set of morphological traits (wing length, tarsus length, bill depth and bill length) in a wild population of great tits (Parus major) from Wytham Woods, UK. Specifically, we quantified the microevolutionary impacts of ISC by combining intra- and intersex additive genetic (co)variances and sex-specific selection estimates in a multivariate framework. Large genetic correlations between homologous male and female traits combined with evidence for sex-specific multivariate survival selection suggested that ISC could play an appreciable role in the evolution of this population. Together, multivariate sex-specific selection and additive genetic (co)variance for the traits considered accounted for additive genetic variance in fitness that was uncorrelated between the sexes (cross-sex genetic correlation = -0.003, 95% CI = -0.83, 0.83). Gender load, defined as the reduction in a population's rate of adaptation due to sex-specific effects, was estimated at 50% (95% CI = 13%, 86%). This study provides novel insights into the evolution of sexual dimorphism in wild populations and illustrates how quantitative genetics and selection analyses can be combined in a multivariate framework to quantify the microevolutionary impacts of ISC.

Validation of a family-centred outcome questionnaire for pinnaplasty: a cross-sectional pilot study.

OBJECTIVES: Comparison of pinnaplasty techniques is difficult due to variation in the reporting of outcomes. We aimed to develop a family-centred outcome questionnaire for use after pinnaplasty and assess it for reliability and validity. DESIGN: Cross-sectional study. SETTING: Tertiary referral paediatric otolaryngology centre. PARTICIPANTS: 20 prospective and 71 retrospective pinnaplasty patients and their parent(s). METHODS: The Post-Operative Pinnaplasty Questionnaire (POPQ) was developed after semi-structured interview with families of children undergoing pinnaplasty. Children aged 4-16 were recruited. Three different ear measurements (auriculocephalic angle, helix-mastoid distance and Walker's ratio) were performed pre-operatively. Children were reviewed 3 months post-operatively and asked to complete a POPQ and Glasgow Children's Benefit Inventory with their parent(s). Ear measurements were repeated and data collected on surgical technique and complications. 200 retrospective pinnaplasty patients were posted a POPQ and Glasgow Children's Benefit Inventory and data collected on surgical technique, complication rate and Walker's angle. MAIN OUTCOMES MEASURES: Validity and reliability of the POPQ. RESULTS: Age range was 4-16 (median 12). POPQ correlated well with Glasgow Children's Benefit Inventory (Spearman's rho = 0.776, P < 0.001). There was no correlation of POPQ scores with age, sex, complication or surgical technique. POPQ score was not associated with severe prominence pre-op nor change or degree of prominence post-op. POPQ displayed good internal consistency (Cronbach's alpha 0.850) and ease-of-use scores. CONCLUSIONS: We have developed a family-focused outcome tool for pinnaplasty that displays good face validity, internal consistency and correlation with health-related quality of life and that is simple and easy to use. No correlation was seen with more traditional measures of outcome such as complications or ear measurements. Further refinement and testing of validity and reliability on a larger sample is planned.

An interventional airway delivery service for congenital high airway obstruction.

BACKGROUND: Congenital airway obstruction is rare but potentially fatal. We developed a complex airways interventional delivery team to manage such cases. Antenatal imaging detects airway compromise at an early stage and facilitates the planning of delivery procedures ('ex utero intrapartum treatment' and 'operation on placental support') which maintain feto-placental circulation whilst an airway is secured. METHOD: A retrospective review was performed of cases in which ENT input was required at birth for airway obstruction. RESULTS: Four neonates were delivered before implementation of the service: two were intubated and another two underwent tracheostomy but died in the peri-natal period. Seven neonates were delivered after implementation of the service: six were intubated and one underwent immediate tracheostomy. Five subsequently underwent tracheostomy (three have since been decannulated). One child with multiple congenital anomalies died due to respiratory failure. Airway obstruction was caused by lymphatic malformation, teratoma, costo-craniomandibular syndrome and choristoma. CONCLUSION: In the absence of other anomalies, interventional airway delivery led to reduced mortality and improved outcomes.

Anatomical variations of the temporal bone on high-resolution computed tomography imaging: how common are they?

OBJECTIVES: This study aimed to evaluate the prevalence of normal variations of temporal bone anatomy on high-resolution computed tomography imaging and report their clinical importance. METHODS: A retrospective review was conducted of high-resolution temporal bone computed tomography imaging performed at NHS Greater Glasgow and Clyde over an eight-year period. The presence of five variants was determined. These variants were: a high dehiscent jugular bulb, an anteriorly located sigmoid sinus, a deep sinus tympani, an enlarged cochlear aqueduct and a large internal auditory meatus. RESULTS: A total of 339 temporal bones were examined. The incidences of a high dehiscent jugular bulb, anteriorly located sigmoid sinus, deep sinus tympani, enlarged cochlear aqueduct and an enlarged internal auditory meatus were 2.76 per cent, 2.94 per cent, 5.01 per cent, 0.58 per cent and 1.76 per cent respectively. CONCLUSION: Anatomical variations of the temporal bone are not uncommon and it is important for the investigating otologist to be aware of such variations prior to undertaking surgery.

Interplay of robustness and plasticity of life-history traits drives ecotypic differentiation in thermally distinct habitats.

Phenotypic plasticity describes the ability of an individual to alter its phenotype in response to the environment and is potentially adaptive when dealing with environmental variation. However, robustness in the face of a changing environment may often be beneficial for traits that are tightly linked to fitness. We hypothesized that robustness of some traits may depend on specific patterns of plasticity within and among other traits. We used a reaction norm approach to study robustness and phenotypic plasticity of three life-history traits of the collembolan Orchesella cincta in environments with different thermal regimes. We measured adult mass, age at maturity and growth rate of males and females from heath and forest habitats at two temperatures (12 and 22 °C). We found evidence for ecotype-specific robustness of female adult mass to temperature, with a higher level of robustness in the heath ecotype. This robustness is facilitated by plastic adjustments of growth rate and age at maturity. Furthermore, female fecundity is strongly influenced by female adult mass, explaining the importance of realizing a high mass across temperatures for females. These findings indicate that different predicted outcomes of life-history theory can be combined within one species' ontogeny and that models describing life-history strategies should not assume that traits like growth rate are maximized under all conditions. On a methodological note, we report a systematic inflation of variation when standard deviations and correlation coefficients are calculated from family means as opposed to individual data within a family structure.

Newborn screening for X-linked adrenoleukodystrophy in New York State: diagnostic protocol, surveillance protocol and treatment guidelines.

PURPOSE: To describe a diagnostic protocol, surveillance and treatment guidelines, genetic counseling considerations and long-term follow-up data elements developed in preparation for X-linked adrenoleukodystrophy (X-ALD) newborn screening in New York State. METHODS: A group including the director from each regional NYS inherited metabolic disorder center, personnel from the NYS Newborn Screening Program, and others prepared a follow-up plan for X-ALD NBS. Over the months preceding the start of screening, a series of conference calls took place to develop and refine a complete newborn screening system from initial positive screen results to long-term follow-up. RESULTS: A diagnostic protocol was developed to determine for each newborn with a positive screen whether the final diagnosis is X-ALD, carrier of X-ALD, Zellweger spectrum disorder, acyl CoA oxidase deficiency or D-bifunctional protein deficiency. For asymptomatic males with X-ALD, surveillance protocols were developed for use at the time of diagnosis, during childhood and during adulthood. Considerations for timing of treatment of adrenal and cerebral disease were developed. CONCLUSION: Because New York was the first newborn screening laboratory to include X-ALD on its panel, and symptoms may not develop for years, long-term follow-up is needed to evaluate the presented guidelines.

Cholesteatoma has a high prevalence in Turner syndrome, highlighting the need for earlier diagnosis and the potential benefits of otoscopy training for paediatricians.

AIM: Girls with Turner syndrome are prone to cholesteatoma, a serious suppurative middle ear disease. We aimed to confirm its high prevalence in Turner syndrome, identify risk factors and suggest possible strategies for earlier detection. METHODS: We reviewed 179 girls with Turner syndrome between 1989 and 2012 to identify cases of cholesteatoma. RESULTS: Seven girls (3.9%) had cholesteatoma (index girls) and each was compared with three age-matched girls without cholesteatoma (comparison girls). All the index girls had either the 45,X or 45,X/46X,i(Xq) karyotypes. Nine ears were initially affected, with three recurrences in two girls. Median age at first cholesteatoma presentation was 11.9 years (range: 7.5-15.2), with otorrhoea for three (range: one to seven) months in all 12 affected ears. Index girls had a significantly higher proportion of previous recurrent acute (p = 0.007) and chronic otitis media (p = 0.008), chronic perforation (p = 0.038) aural polyps (p < 0.0001) and tympanic membrane retraction (p = 0.0001) than comparison girls. CONCLUSION: Cholesteatoma has a high prevalence in Turner syndrome. Risk factors include 45,X and 46,XiXq karyotypes; a history of chronic otitis media, tympanic membrane retraction and persistent otorrhoea; and older age. Earlier recognition of ear disease is needed and otoscopy training for paediatricians caring for Turner syndrome patients may be beneficial.

Real evaporative cooling efficiency of one-layer tight-fitting sportswear in a hot environment.

Real evaporative cooling efficiency, the ratio of real evaporative heat loss to evaporative cooling potential, is an important parameter to characterize the real cooling benefit for the human body. Previous studies on protective clothing showed that the cooling efficiency decreases with increasing distance between the evaporation locations and the human skin. However, it is still unclear how evaporative cooling efficiency decreases as the moisture is transported from the skin to the clothing layer. In this study, we performed experiments with a sweating torso manikin to mimic three different phases of moisture absorption in one-layer tight-fitting sportswear. Clothing materials Coolmax(®) (CM; INVISTA, Wichita, Kansas, USA; 100%, profiled cross-section polyester fiber), merino wool (MW; 100%), sports wool (SW; 50% wool, 50% polyester), and cotton (CO; 100%) were selected for the study. The results demonstrated that, for the sportswear materials tested, the real evaporative cooling efficiency linearly decreases with the increasing ratio of moisture being transported away from skin surface to clothing layer (adjusted R(2) >0.97). In addition, clothing fabric thickness has a negative effect on the real evaporative cooling efficiency. Clothing CM and SW showed a good ability in maintaining evaporative cooling efficiency. In contrast, clothing MW made from thicker fabric had the worst performance in maintaining evaporative cooling efficiency. It is thus suggested that thin fabric materials such as CM and SW should be used to manufacture one-layer tight-fitting sportswear.

Cholesteatoma surgery in children: 10-year retrospective review.

OBJECTIVE: To review outcomes following paediatric cholesteatoma surgery performed between 1999 and 2009 in a tertiary paediatric ENT unit. STUDY DESIGN: Retrospective case note review. RESULTS: A total of 137 mastoid procedures were recorded. Fifty-four per cent of children were observed to have disease involving the entire middle-ear cleft and mastoid complex. The revision rate was 25 per cent. Time to recurrence was one to three years in 17 patients, three to six years in five patients, and six to nine years in three cases. Eight of 25 revision cases demonstrated spontaneous improvement in air conduction thresholds following primary surgery. A high facial ridge and inadequate meatoplasty correlated highly with disease recurrence. CONCLUSION: Children tend to present with aggressive disease. Disease extent and ossicular chain involvement are associated with a higher risk of recurrent disease. Spontaneous improvement in hearing thresholds following cholesteatoma surgery should alert the clinician to recurrent disease.

HeartBeat--improving heart attack care.

We aimed to save lives by assuring best practice in ST elevation myocardial infarction (STEMI) through initiating the Institute for Healthcare Improvement (IHI) methodology nationally. Following collection of a minimum dataset, annual change in indicators in the five initiating hospitals for the period Oct 2006 - Sept 2009 was assessed by analysing the percentage of patients receiving the eight components of evidenced based care on admission and discharge and in-hospital mortality rate. For 635 patients, performance on seven of the eight indicators of care exceeded 90% annually. Timely reperfusion therapy (thrombolysis, primary percutaneous coronary intervention (PPCI)) improved non-significantly from 68.2% (107 patients) in year 1 to 77.1% (118 patients) in year 3. In-hospital mortality declined significantly from 12.4% (24 deaths) in year 1 to 5% (9 deaths) in year 3. Evidence based STEMI care is followed to a high degree but timely reperfusion and PPCI provision remain a challenge nationally.

Newborn screening for Tyr-I: two years' experience of the New York State program.

In 2 years, the New York newborn screening program has analyzed approximately 500,000 samples for succinylacetone (SUAC), the biomarker for Tyrosinemia, type I. There have been five screen-positive results. Two of these results were considered borderline, and a repeat specimen was requested. In three cases, an immediate referral was made to a specialty care center. Two of those three cases were confirmed for Tyr-I.

Indirect genetics effects and evolutionary constraint: an analysis of social dominance in red deer, Cervus elaphus.

By determining access to limited resources, social dominance is often an important determinant of fitness. Thus, if heritable, standard theory predicts mean dominance should evolve. However, dominance is usually inferred from the tendency to win contests, and given one winner and one loser in any dyadic contest, the mean proportion won will always equal 0.5. Here, we argue that the apparent conflict between quantitative genetic theory and common sense is resolved by recognition of indirect genetic effects (IGEs). We estimate selection on, and genetic (co)variance structures for, social dominance, in a wild population of red deer Cervus elaphus, on the Scottish island of Rum. While dominance is heritable and positively correlated with lifetime fitness, contest outcomes depend as much on the genes carried by an opponent as on the genotype of a focal individual. We show how this dependency imposes an absolute evolutionary constraint on the phenotypic mean, thus reconciling theoretical predictions with common sense. More generally, we argue that IGEs likely provide a widespread but poorly recognized source of evolutionary constraint for traits influenced by competition.

Evolution of adaptive diversity and genetic connectivity in Arctic charr (Salvelinus alpinus) in Iceland.

The ecological theory of adaptive radiation predicts that the evolution of phenotypic diversity within species is generated by divergent natural selection arising from different environments and competition between species. Genetic connectivity among populations is likely also to have an important role in both the origin and maintenance of adaptive genetic diversity. Our goal was to evaluate the potential roles of genetic connectivity and natural selection in the maintenance of adaptive phenotypic differences among morphs of Arctic charr, Salvelinus alpinus, in Iceland. At a large spatial scale, we tested the predictive power of geographic structure and phenotypic variation for patterns of neutral genetic variation among populations throughout Iceland. At a smaller scale, we evaluated the genetic differentiation between two morphs in Lake Thingvallavatn relative to historically explicit, coalescent-based null models of the evolutionary history of these lineages. At the large spatial scale, populations are highly differentiated, but weakly structured, both geographically and with respect to patterns of phenotypic variation. At the intralacustrine scale, we observe modest genetic differentiation between two morphs, but this level of differentiation is nonetheless consistent with strong reproductive isolation throughout the Holocene. Rather than a result of the homogenizing effect of gene flow in a system at migration-drift equilibrium, the modest level of genetic differentiation could equally be a result of slow neutral divergence by drift in large populations. We conclude that contemporary and recent patterns of restricted gene flow have been highly conducive to the evolution and maintenance of adaptive genetic variation in Icelandic Arctic charr.

The danger of applying the breeder's equation in observational studies of natural populations.

The breeder's equation, which predicts evolutionary change when a phenotypic covariance exists between a heritable trait and fitness, has provided a key conceptual framework for studies of adaptive microevolution in nature. However, its application requires strong assumptions to be made about the causation of fitness variation. In its univariate form, the breeder's equation assumes that the trait of interest is not correlated with other traits having causal effects on fitness. In its multivariate form, the validity of predicted change rests on the assumption that all such correlated traits have been measured and incorporated into the analysis. Here, we (i) highlight why these assumptions are likely to be seriously violated in studies of natural, rather than artificial, selection and (ii) advocate wider use of the Robertson-Price identity as a more robust, and less assumption-laden, alternative to the breeder's equation for applications in evolutionary ecology.