Diagnosis and management of selective fetal growth restriction in monochorionic twin pregnancies: A cross-sectional international survey.

OBJECTIVE: To identify current practices in the management of selective fetal growth restriction (sFGR) in monochorionic diamniotic (MCDA) twin pregnancies. DESIGN: Cross-sectional survey. SETTING: International. POPULATION: Clinicians involved in the management of MCDA twin pregnancies with sFGR. METHODS: A structured, self-administered survey. MAIN OUTCOME MEASURES: Clinical practices and attitudes to diagnostic criteria and management strategies. RESULTS: Overall, 62.8% (113/180) of clinicians completed the survey; of which, 66.4% (75/113) of the respondents reported that they would use an estimated fetal weight (EFW) of <10th centile for the smaller twin and an inter-twin EFW discordance of >25% for the diagnosis of sFGR. For early-onset type I sFGR, 79.8% (75/94) of respondents expressed that expectant management would be their routine practice. On the other hand, for early-onset type II and type III sFGR, 19.3% (17/88) and 35.7% (30/84) of respondents would manage these pregnancies expectantly, whereas 71.6% (63/88) and 57.1% (48/84) would refer these pregnancies to a fetal intervention centre or would offer fetal intervention for type II and type III cases, respectively. Moreover, 39.0% (16/41) of the respondents would consider fetoscopic laser surgery (FLS) for early-onset type I sFGR, whereas 41.5% (17/41) would offer either FLS or selective feticide, and 12.2% (5/41) would exclusively offer selective feticide. For early-onset type II and type III sFGR cases, 25.9% (21/81) and 31.4% (22/70) would exclusively offer FLS, respectively, whereas 33.3% (27/81) and 32.9% (23/70) would exclusively offer selective feticide. CONCLUSIONS: There is significant variation in clinician practices and attitudes towards the management of early-onset sFGR in MCDA twin pregnancies, especially for type II and type III cases, highlighting the need for high-level evidence to guide management.

Developing a cognitive assessment toolkit for primary care: qualitative assessment of providers' needs and perceptions of usability in clinical practice.

BACKGROUND: Burden of dementia is expected to substantially increase. Early dementia is underdiagnosed in primary care. Given the benefits of active management of dementia, earlier detection in primary care is imperative. The aim of this study was to understand primary care provider (PCP) perceptions of implementing a cognitive assessment toolkit in primary care. METHODS: PCPs in a large health system in the US were recruited to a qualitative study utilizing semi-structured interviews. Interviews captured provider perceptions of options for implementing a cognitive assessment toolkit derived from the Gerontological Society of America (GSA) KAER (Kickstart, Assess, Evaluate, Refer) toolkit, including a workflow and adapted clinical tools. A content analysis approach distinguished themes and exemplary quotes. RESULTS: Ten PCPs were interviewed. They found the toolkit useful, felt the term Kickstart was not specific to dementia care, and stressed that addressing cognitive evaluation would need to be easy to implement in a clinical workflow. Finally, providers knew many resources for referral but were unsure how to help patients navigate options. CONCLUSIONS: Providers stressed simplicity, ease, and efficiency for implementation of a cognitive assessment toolkit. Incorporating these findings into the development of clinical tools and workflows may increase cognitive evaluations conducted by PCPs.

Mixed-methods feasibility study to inform a randomised controlled trial of proton pump inhibitors to reduce strictures following neonatal surgery for oesophageal atresia.

OBJECTIVES: This mixed-methods feasibility study aimed to explore parents' and medical practitioners' views on the acceptability and design of a clinical trial to determine whether routine prophylactic proton pump inhibitors (PPI) reduce the incidence of anastomotic stricture in infants with oesophageal atresia (OA). DESIGN: Semi-structured interviews with UK parents of an infant with OA and an online survey, telephone interviews and focus groups with clinicians. Data were analysed using reflexive thematic analysis and descriptive statistics. PARTICIPANTS AND SETTING: We interviewed 18 parents of infants with OA. Fifty-one clinicians (49 surgeons, 2 neonatologists) from 20/25 (80%) units involved in OA repair completed an online survey and 10 took part in 1 of 2 focus groups. Interviews were conducted with two clinicians whose survey responses indicated they had concerns about the trial. OUTCOME MEASURES: Parents and clinicians ranked the same top four outcomes ('Severity of anastomotic stricture', 'Incidence of anastomotic stricture', 'Need for treatment of reflux' and 'Presence of symptoms of reflux') as important to measure for the proposed trial. RESULTS: All parents and most clinicians found the use, dose and duration of omeprazole as the intervention medication, and the placebo control, as acceptable. Parents stated they would hypothetically consent to their child's participation in the trial. Concerns of a few parents and clinicians about infants suffering with symptomatic reflux, and the impact of this for study retention, appeared to be alleviated through the symptomatic reflux treatment pathway. Hesitant clinician views appeared to change through discussion of parental support for the study and by highlighting existing research that questions current practice of PPI treatment. CONCLUSIONS: Our findings indicate that parents and most clinicians view the proposed Treating Oesophageal Atresia with prophylactic proton pump inhibitors to prevent STricture (TOAST) trial to be feasible and acceptable so long as infants can be given PPI if clinicians deem it clinically necessary. This insight into parent and clinician views and concerns will inform pilot phase trial monitoring, staff training and the development of the trial protocol.

'I feel like my house was taken away from me': Parents' experiences of having home adaptations for their medically complex, technology-dependent child.

Technology-dependent children are a sub-population of seriously ill children with life-limiting conditions who are being cared for at home by their families. Although home-based care has been the model of care for these children since the late 1980s, there is a paucity of literature about parents' experiences of having home adaptations made to enable their home to be a place of care for their child. Using the findings from auto-driven photo-elicitation interviews conducted between August 2017 and June 2018 with 12 parents (10 mothers and 2 fathers) who have a technology-dependent child (aged 5-25 years) living in England, Scotland and Wales and David Seamon's five concepts of at-homeness (appropriation, at-easeness, regeneration, rootedness and warmth) as a conceptual framework, this paper addresses how parents' experienced home adaptations. Thematic analysis generated a meta-theme of 'Home needs to be a home for all family members' and the three key themes: (1) 'You just get told' and 'you're not involved'; (2) It's just the 'cheapest', 'quickest', 'short-term' approach; (3) Having 'control' and 'thinking things through.' The need to involve parents in decision-making about adaptations that are made to their home (family-informed design) is clear, not only from a cost-saving perspective for the state, but for creating an aesthetic and functional home that optimises health, well-being and feelings of at-homeness for the entire family.

'It doesn't feel like our house anymore': The impact of medical technology upon life at home for families with a medically complex, technology-dependent child.

The study aimed to identify how medical technology impacts upon the home and life at home. Inductive auto-driven photo-elicitation or semi-structured interviews were conducted with technology-dependent children/young people (n = 2) and their family members (n = 15) from 10 families. Thematic analysis generated three themes: Altered physicality and look of the home; Altered sounds in the home; and 'It's worth it! Technology enables us to stay as a family'. Fundamentally, the detrimental impacts of living with medical technology were perceived as worth it as these enabled their child to be at home. Home was not home, and families were incomplete without their child at home.

Comparison of cellular immune responses to avian influenza virus in two genetically distinct, highly inbred chicken lines.

Low pathogenicity avian influenza causes mild disease involving the respiratory, gastrointestinal, and reproductive systems of wild and domestic birds. Avian influenza research often emphasizes the effect of the virus genetics on disease, but the influence of host genetics on resistance to infection is not well understood. The genetic determinants of enhanced resistance to influenza can be explored by using genetically distinct, highly inbred chicken lines that differ in susceptibility to influenza. In this study, we compared the mucosal cellular immune responses between the relatively resistant Fayoumi M43 chicken line and the relatively susceptible Leghorn GB2 chicken line after challenging with low pathogenicity avian influenza virus (LPAIV) H6N2. The birds were inoculated at 21 days of age with 107 50 % egg infective dose (EID50) LPAIV H6N2 via nasal and tracheal routes in two separate experiments. Clinical signs were recorded, tracheal swabs were collected to measure viral titer, and tracheas and lungs were harvested for flow cytometric analysis of macrophage, B cell, and T cell populations at 4 days post-infection (dpi) (Experiments 1 and 2) and 6 dpi (Experiment 2). Blood and tears were also collected at 7 and 14 dpi (Experiment 1) to measure antibody levels. Compared to both the non-challenged Fayoumis and the relatively susceptible Leghorn chickens, relatively resistant Fayoumi chickens challenged with LPAIV demonstrated enhanced MHC class I expression on antigen-presenting cells and increased macrophage, B cell, and T cell frequencies in the trachea, which were associated with reduced tracheal viral titers at 4 dpi. In contrast, MHC class I expression and immune cell frequencies in the trachea were not different between challenged Leghorns and non-challenged Leghorns. Furthermore, Leghorns shed higher virus titers in their trachea compared to Fayoumis. Challenged Fayoumis and Leghorns both produced AIV-specific IgY detected in the serum and tears, but AIV-specific IgA was not detected in the tears. In this study, we provide new insight into immune mechanisms of enhanced resistance to avian influenza in chickens, which may lead to improved vaccination strategies and breeding programs.

Genetic variation and selection of MHC class I loci differ in two congeneric frogs.

Major histocompatibility complex (MHC) genes encode proteins in the acquired immune response pathway that often show distinctive selection-driven patterns in wild vertebrate populations. We examined genetic variation and signatures of selection in the MHC class I alpha 1 (A1)- and alpha 2 (A2)-domain encoding exons of two frog congeners [Agalychnis callidryas (n = 20) and A. lemur (n = 20)] from a single locality in Panama. We also investigated how historical demographic processes may have impacted MHC genetic diversity by analyzing a neutral mitochondrial marker. We found that both MHC domains were highly variable in both species, with both species likely expressing three loci. Our analyses revealed different signatures of selection between the two species, most notably that the A. callidryas A2 domain had experienced positive selection while the A2 domain of A. lemur had not. Diversifying selection acted on the same number of A1 and A2 allelic lineages, but on a higher percentage of A1 sites compared to A2 sites. Neutrality tests of mitochondrial haplotypes predominately indicated that the two species were at genetic equilibrium when the samples were collected. In addition, two historical tests of demography indicated both species have had relatively stable population sizes over the past 100,000 years; thus large population size changes are unlikely to have greatly influenced MHC diversity in either species during this time period. In conclusion, our results suggest that the impact of selection on MHC diversity varied between these two closely related species, likely due to a combination of distinct ecological conditions and past pathogenic pressures.

Fasting or fear: disentangling the roles of predation risk and food deprivation in the nitrogen metabolism of consumers.

Predators can alter nutrient cycles simply by inducing stress in prey. This stress accelerates prey's protein catabolism, nitrogen waste production, and nitrogen cycling. Yet predators also reduce the feeding rates of their prey, inducing food deprivation that is expected to slow protein catabolism and nitrogen cycling. The physiology of prey under predation risk thus balances the influences of predation risk and food deprivation, and this balance is central to understanding the role of predators in nutrient cycles. We explored the separate and combined effects of predation risk and food deprivation on prey physiology and nutrient cycling by exposing guppies (Poecilia reticulata) to predation risk and food deprivation in a 2 × 2 design. We simulated predation risk using chemical cues from a natural predator of guppies, and we created food deprivation by rationing food availability. We measured guppy response as food consumption, growth, tissue energy density, tissue carbon:nitrogen, and nitrogen (N) excretion and assimilation. We found that N-linked physiological processes (N consumption, assimilation, excretion) were strongly affected by predation risk, independent of food consumption. Guppies excreted substantially less under predation risk than they did under food deprivation or control conditions. These results suggest that predation risk, per se, triggers physiological changes in guppies that increase N retention and decrease N excretion. We suggest that slower N metabolism under predation risk is an adaptive response that minimizes protein loss in the face of predictable, predator-induced food restriction. Notably, N metabolism shares common hormonal control with food seeking behavior, and we speculate that increased N retention is a direct and immediate result of reduced food seeking under predation risk. Contrary to predation-stress-based hypotheses for how predators affect nutrient cycling by prey, our result indicates that even short-term exposure to predators may decelerate, rather than accelerate, the speed of N cycling by suppressing N turnover by prey.

Borrelia burgdorferi Manipulates Innate and Adaptive Immunity to Establish Persistence in Rodent Reservoir Hosts.

Borrelia burgdorferi sensu lato species complex is capable of establishing persistent infections in a wide variety of species, particularly rodents. Infection is asymptomatic or mild in most reservoir host species, indicating successful co-evolution of the pathogen with its natural hosts. However, infected humans and other incidental hosts can develop Lyme disease, a serious inflammatory syndrome characterized by tissue inflammation of joints, heart, muscles, skin, and CNS. Although B. burgdorferi infection induces both innate and adaptive immune responses, they are ultimately ineffective in clearing the infection from reservoir hosts, leading to bacterial persistence. Here, we review some mechanisms by which B. burgdorferi evades the immune system of the rodent host, focusing in particular on the effects of innate immune mechanisms and recent findings suggesting that T-dependent B cell responses are subverted during infection. A better understanding of the mechanisms causing persistence in rodents may help to increase our understanding of the pathogenesis of Lyme disease and ultimately aid in the development of therapies that support effective clearance of the bacterial infection by the host's immune system.

Positive selection drives the evolution of a major histocompatibility complex gene in an endangered Mexican salamander species complex.

Immune gene evolution can be critical to species survival in the face of infectious disease. In particular, polymorphism in the genes of the major histocompatibility complex (MHC) helps vertebrates combat novel and diverse pathogens by increasing the number of pathogen-derived proteins that can initiate the host's acquired immune response. In this study, we used a combination of presumably adaptive and neutral markers to investigate MHC evolution in populations of five salamander species within the Ambystoma velasci complex, a group consisting of 15 recently diverged species, several of which are endangered. We isolated 31 unique MHC class II ß alleles from 75 total individuals from five species in this complex. MHC heterozygosity was significantly lower than expected for all five species, and we found no clear relationship between number of MHC alleles and species range, life history, or level of heterozygosity. We inferred a phylogeny representing the evolutionary history of Ambystoma MHC, with which we found signatures of positive selection on the overall gene, putative peptide-binding residues, and allelic lineages. We identified several instances of trans-species polymorphism, a hallmark of balancing selection observed in other groups of closely related species. In contrast, we did not detect comparable allelic diversity or signatures of selection on neutral loci. Additionally, we identified 17 supertypes among the 44 unique Ambystoma alleles, indicating that these sequences may encode functionally distinct MHC variants. We therefore have strong evidence that positive selection is a major evolutionary force driving patterns of MHC polymorphism in this recently radiated species complex.

StaphPlex system for rapid and simultaneous identification of antibiotic resistance determinants and Panton-Valentine leukocidin detection of staphylococci from positive blood cultures.

Phenotypic methods take several days for identification and antimicrobial susceptibility testing of staphylococcal isolates after gram-positive cocci in clusters (GPCC) are observed in positive blood cultures. We developed and validated a StaphPlex system that amplifies and detects 18 gene targets simultaneously in 1 reaction for species-level identification of staphylococci, detection of genes encoding Panton-Valentine leukocidin (PVL), and antimicrobial resistance determinants of staphylococci. The StaphPlex system was compared to phenotypic methods for organism identification and antimicrobial resistance detection for positive blood culture specimens in which GPCC were observed. Among a total of 360 GPCC specimens, 273 (75.8%), 37 (10.3%), 37 (10.3%), 1 (0.3%), 3 (0.8%), and 9 (2.5%) were identified by StaphPlex as coagulase-negative Staphylococcus (CoNS), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), or mixed infections of CoNS and MRSA, CoNS and MSSA, or nonstaphylococci, respectively, with an overall accuracy of 91.7%. The 277 CoNS-containing specimens were further identified to the species level as containing 203 (73.3%) Staphylococcus epidermidis isolates, 10 (3.6%) Staphylococcus haemolyticus isolates, 27 (9.7%) Staphylococcus hominis isolates, 1 (0.4%) Staphylococcus lugdunensis isolate, and 36 (13.0%) other CoNS isolates, with an overall accuracy of 80.1% compared to an API STAPH test and CDC reference identification. Numerous very major errors were noticed when detection of aacA, ermA, ermC, tetM, and tetK was used to predict in vitro antimicrobial resistance, but relatively few major errors were observed when the absence of these genes was used to predict susceptibility. The StaphPlex system demonstrated 100% sensitivity and specificity, ranging from 95.5% to 100.0% when used for staphylococcal cassette chromosome mec typing and PVL detection. StaphPlex provides simultaneous staphylococcal identification and detection of PVL and antimicrobial resistance determinants within 5 h, significantly shortening the time needed for phenotypic identification and antimicrobial susceptibility testing.

Degradation of volatile hydrocarbons from steam-classified solid waste by a mixture of aromatic hydrocarbon-degrading bacteria.

Steam classification is a process for treatment of solid waste that allows recovery of volatile organic compounds from the waste via steam condensate and off-gases. A mixed culture of aromatic hydrocarbon-degrading bacteria was used to degrade the contaminants in the condensate, which contained approx. 60 hydrocarbons, of which 38 were degraded within 4 d. Many of the hydrocarbons, including styrene, 1,2,4-trimethylbenzene, naphthalene, ethylbenzene, m-/p-xylene, chloroform, 1,3-dichloropropene, were completely or nearly completely degraded within one day, while trichloroethylene and 1,2,3-trichloropropane were degraded more slowly.

Degradation of mixtures of aromatic and chloroaliphatic hydrocarbons by aromatic hydrocarbon-degrading bacteria.

The well-characterized toluene-oxidizing bacteria Pseudomonas putida PaW1, P. putida F1, P. mendocina KR1, Burkholderia cepacia G4, B. cepacia JS150, and Ralstonia pickettii PKO1, as well as several strains of bacteria isolated from activated sludge, were examined for their ability to degrade mixtures of aromatic and chloroaliphatic hydrocarbons. Collectively, the strains tested were able to transform all of the 14 aromatic hydrocarbons included in the mixtures, with most strains degrading five or more. Few strains degraded trichloroethylene well under these conditions, only one degraded methylene chloride, and none were able to transform chloroform. G4, PKO1, KR1, F1, and JS150 exhibited generally broad but oxygenase-specific degradation profiles, with the three monooxygenase strains degrading significantly more o-xylene and trichloroethylene, and F1 and JS150 degrading greater quantities of isopropylbenzene and 1,4-dichlorobenzene. PaW1 degraded only the methylaromatic hydrocarbons and styrene. Sludge isolates enriched on benzene, toluene, styrene and the xylenes exhibited degradation profiles similar to F1 or PaW1, while the pattern of hydrocarbon degradation for the ethylbenzene, isopropylbenzene, 1,3,5-trimethylbenzene, and 1,3-dichlorobenzene isolates were distinct from the other strains and from each other. Overall, our results showed that many of the bacteria which utilize aromatic compounds are capable of degrading a diverse array of aromatic hydrocarbons in mixtures, but that chloroaliphatics such as methylene chloride and chloroform may be recalcitrant to co-oxidation in the presence of aromatics or trichloroethylene.