ABSTRACT
The Reflective-Impulsive Dual Processes Model suggests that overeating occurs when the temptation to consume food overrides inhibitory control processes. However, how rewards interact with inhibitory control and their relation to children's weight status and food intake is not understood. Here, 7-to-11-year-old children (n = 66; 32 overweight/obese) completed two versions (baseline [i.e., non-reward incentivized/control] and reward incentivized [food, money, no reward]) of a Go/Nogo task. Intake of palatable foods in the absence of hunger (i.e., eating in the absence of hunger-EAH) was measured following a standardized meal. A drift diffusion model was used to characterize children's performance parameters on the Go/Nogo. On the baseline Go/Nogo, children with higher weight status responded more cautiously, but on reward trials for food/money children were more cautions and made more false alarms relative to the no reward condition. Energy intake during EAH positively correlated with FA errors for food and money vs. no reward, but sex moderated this effect such that FA positively associated with EAH in girls but not boys. Independent of sex, FA for money vs. no reward and food vs. money were both positively associated with energy consumed during EAH. These results suggest that the presence of food and money rewards impair inhibitory control processing, especially in children with higher weight status. Further, increased inhibitory control impairment in response to food rewards, specifically, may be a risk factor for disinhibited eating in girls. Though preliminary, results may be useful in the development of targeted treatments to help moderate excess consumption in children.
Subject(s)
Feeding Behavior , Hunger , Child , Eating , Female , Humans , Hyperphagia , Meals , RewardABSTRACT
We previously generated a high-metabolizable energy (HME) perennial ryegrass (Lolium perenne) by genetically modifying the plant to increase the leaf lipid content. Although substantial progress has been made toward characterizing physiological changes of HME ryegrass, very limited information exists for feeding value and its suitability for adoption into the pastoral system. In this study, independent HME ryegrass lines with a range of elevated leaf lipid concentrations were analyzed for changes in fatty acids and possible associated changes in the broader nutritional profile, including the gross energy, which was found to increase by 6.8%. Because ryegrass is often ensiled and fermentation in the rumen leads to biohydrogenation of fatty acids as well as enteric methane production, we sought to investigate these effects on HME ryegrass. This was achieved by performing mini-scale silos and using an automated gas measurement system to incubate the material in rumen fluid in vitro for 24 h. Our study included treatments comprising 3 independent HME ryegrass genotypes and wild-type control materials prepared fresh and as silage, employing in total 5 incubation studies, using rumen fluids collected from 4 nonlactating Jersey × Holstein cows. At intervals during the incubation, the production of gases, volatile fatty acids, and the degree of biohydrogenation were measured. Statistical data analysis indicated that differences in the nutritional compositions of the ensiled materials largely reflected those of their fresh counterparts. Incubation of both fresh and ensiled HME ryegrass in rumen fluid resulted in: (1) a greater percentage of valuable unsaturated fatty acids compared with the control; (2) a significant reduction of butyrate; and (3) a 10 to 15% decrease in the methane proportion of the total gas production. We conclude that ensiling could be a convenient option for preserving HME as a locally produced high-value supplementary feed; however, large-scale application needs to be investigated. In this paper we discuss the potential use of HME ryegrass to enhancing forage feeding value and the potential environmental benefits to the pastoral agriculture industry.
Subject(s)
Cattle/metabolism , Lolium/metabolism , Methane/biosynthesis , Rumen/metabolism , Silage , Animals , Butyrates/metabolism , Digestion , Energy Metabolism , Fatty Acids, Volatile/metabolism , Female , Fermentation , Lolium/genetics , Plants, Genetically ModifiedABSTRACT
A High Purity Germanium (HPGe) detector has been used to measure the photon spectra in the majority of monoenergetic neutron fields produced at NPL (0.144, 0.250, 0.565, 2.0, 5.0 and 16.5 MeV). The HPGe was characterised and then modelled to produce a response matrix. The measured pulse height spectra were then unfolded to produce photon fluence spectra. The new spectra were used to improve the photon to neutron dose equivalent ratios from some earlier work at NPL with Geiger-Muller tubes and electronic personal dosemeters.
Subject(s)
Neutrons , Radiometry , Radiation Dosage , Photons , CalibrationABSTRACT
Patients referred to secondary care for specialist respiratory review frequently undergo multiple hospital attendances for investigations and consultations. This study evaluated the potential of a preclinic telephone consultation and subsequent coordination of tests and face-to-face consultations to reduce hospital visits. Total hospital attendances were recorded for three cohorts (participants, non-participants and comparators) for 6 months from first specialist contact. Patients completed the medical interview satisfaction scale-21 (MISS-21). The study showed that a preclinic telephone consultation can significantly reduce hospital visits over a fixed period without reducing patient satisfaction. In total, 20.8% of the participant group had three or more hospital attendances compared with 42.9% of the non-participant group (p = 0.001) and 44.7% of the comparator group (p = 0.002). Participants had fewer follow up visits and lower rates of non-attendance/late rearrangement of appointments. This service reduces unnecessary hospital visits, seems to improve patient compliance and may save costs associated with non-attendance and follow up consultations.
Subject(s)
Centralized Hospital Services/methods , Continuity of Patient Care , Referral and Consultation/organization & administration , Respiratory Tract Diseases , Telephone , Adult , Aged , Appointments and Schedules , Continuity of Patient Care/economics , Continuity of Patient Care/organization & administration , Cost Savings/methods , Episode of Care , Female , Follow-Up Studies , Humans , Male , Middle Aged , Outpatient Clinics, Hospital/organization & administration , Outpatient Clinics, Hospital/statistics & numerical data , Patient Participation , Patient Satisfaction/statistics & numerical data , Referral and Consultation/standards , Respiratory Tract Diseases/diagnosis , Respiratory Tract Diseases/therapy , Specialization , Surveys and QuestionnairesABSTRACT
Personalised written action plans are increasingly regarded as an important component of chronic obstructive pulmonary disease (COPD) self-management support and yet they may not be understood by those with limited literacy skills. This study was designed to produce a comprehensible pictorial COPD action plan for use by patients and health care professionals. With advice from a group of doctors and nurses a 'standard' written COPD action plan was translated by a medical artist into a series of pictorial images. These were assessed using the techniques of guessability and translucency in 21 adults attending a COPD clinic in a London hospital. Guessability and translucency scores show that pictograms were reasonably well understood, with only 3 pictograms showing low score in both guessability and translucency questionnaires. These included images depicting increased sputum production, swollen ankles, and use of extra doses of reliever medication. However, after brief spoken reinforcement about self-management, most patients could use the pictorial plan to suggest appropriate self-management behaviour such as when to access medical care. We have developed a pictorial COPD action plan. Pictorial methods represent an effective method of reinforcing the spoken word for all ranges of literacy.
Subject(s)
Community Participation/methods , Computer Graphics , Patient Care Planning , Pulmonary Disease, Chronic Obstructive/therapy , Self Care/methods , Aged , Female , Health Literacy/methods , Humans , Male , Middle Aged , Patient Education as Topic/methodsABSTRACT
The Punjab urial (Ovis vignei punjabiensis) is a globally threatened wild sheep species. In Pakistan the species is legally protected and bred in captivity to release into natural habitats to reinforce wild populations. Vigilance and feeding are critical to survival, though the degree to which captive-bred animals exhibit these behaviours post-release has rarely been investigated. We monitored the daily behaviours of five adult urial after release and classifying behaviours from 0600 hrs to 1800 hrs, replicating each one-hour period twice and recording four observations of each animal per hour. At the herd level, vigilance and feeding behaviours were exhibited equally. Males and females invested equal time in feeding, males were more vigilant (p = 0.001) and more aggressive (p = 0.010), and females were more restful (p = 0.019) or engaged in grooming (p = 0.044) or locomotion (p = 0.002). Females spent more time feeding than being vigilant (p = 0.002). Males maintained high levels of vigilance throughout the day. Patterns of resting 1300 hrs to 1500 hrs and feeding in early morning and late afternoon were common for both sexes. Behaviours classified as 'other' were exhibited equally between sexes. Our results reveal positive indications of captive-bred urial balancing threat detection and energy acquisition post-release and exhibiting natural behaviours and activity patterns. We encourage assessment of survivorship to evaluate long-term effectiveness of captive breeding and release as a candidate restoration programme.
Subject(s)
Ecosystem , Sheep, Domestic , Animals , Female , Male , Pakistan , SheepABSTRACT
BACKGROUND: The delivery of healthcare during the COVID pandemic has had a significant impact on front line staff. Nurses who work with respiratory patients have been at the forefront of the pandemic response. Lessons can be learnt from these nurses' experiences in order to support these nurses during the existing pandemic and retain and mobilise this skilled workforce for future pandemics. METHODS: This study explores UK nurses' experiences of working in a respiratory environment during the COVID-19 pandemic. An e-survey was distributed via professional respiratory societies; the survey included a resilience scale, the GAD7 (anxiety) and the PHQ9 (depression) tools. Demographic data was collected on age, gender, ethnicity, nursing experience and background, clinical role in the pandemic, and home-life and work balance. RESULTS: Two hundred and fifty-five responses were received for the survey, predominately women (89%, 226/255), aged over 35 (79%, 202/255). Nearly 21% (40/191) experiencing moderate to severe or severe symptoms of anxiety. Similar levels are seen for depression (17.2%, 31/181). 18.9% (34/180) had a low or very low resilience score. Regression analysis showed that for both depression and anxiety variables, age and years of qualification provided the best model fit. Younger nurses with less experience have higher levels of anxiety and depression and had lower resilience. CONCLUSION: This cohort experienced significant levels of anxiety and depression, with moderate to high levels of resilience. Support mechanisms and interventions need to be put in place to support all nurses during pandemic outbreaks, particularly younger or less experienced staff.
Subject(s)
Anxiety/epidemiology , COVID-19/therapy , Depression/epidemiology , Nursing Staff/psychology , Resilience, Psychological , Respiratory Therapy , Adult , Age Factors , COVID-19/psychology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , United Kingdom , Young AdultABSTRACT
Respiratory viral infections are commonly associated with altered immune responses, such as proliferative responses to mitogens and antigens. To examine potential mechanisms, we examined production of IL-1 and IL-1 inhibitors by purified human peripheral blood-derived macrophages exposed to influenza virus or respiratory syncytial virus (RSV). IL-1 and IL-1 inhibitor activities in supernatant fluids from macrophages exposed to the viruses 24 h previously were measured using the standard mouse thymocyte comitogen assay. Crude fluids from macrophages exposed to influenza virus contained substantial IL-1 activity, whereas crude fluids from macrophages exposed to RSV contained marked IL-1 inhibitor activity. Assays with gel filtration-separated fractions revealed that both influenza virus and RSV induced production of both IL-1 and IL-1 inhibitors. Neither IL-2 nor IL-2 inhibitor activities were detected. Thus, effects of human macrophage-derived factors on thymocyte proliferation, or potentially on human lymphocyte proliferation, may reflect the total or net activity of multiple composite factors, the balance of which varies according to the challenge. The data raise the possibility that marked production of IL-1 inhibitor activity in response to RSV plays a role in the clinical recurrence of RSV infection despite the absence of clear evidence for antigenic shift or drift of the virus.
Subject(s)
Influenza, Human/immunology , Interleukin-1/biosynthesis , Lymphokines/biosynthesis , Macrophages/immunology , Respirovirus Infections/immunology , Humans , In Vitro Techniques , Influenza A virus , Lymphocyte Activation , Macrophages/metabolism , Respiratory Syncytial VirusesABSTRACT
The identification of corrosion, cracks and defects in pipelines used for transporting oil and gas can reduce the possibility of leaks, and consequently, it can limit the extent of an environmental disaster, public hazard and the associated financial impact of such events. Typically, corrosion in oil pipelines is measured with non-destructive ultrasonic or electromagnetic techniques, on the basis that corrosion and defects are often manifest as a change of thickness in the steel from which pipelines are made. However, such approaches are not practical for underground pipelines and their deployment can be complicated for the case of pipelines covered by insulation. In this paper, we present an innovative, non-destructive testing technique, which exploits the backscatter of a combination of fast-neutron and γ radiation from steel samples of a variety of thicknesses consistent with changes that might arise due to corrosion of a pipe wall. Our research demonstrates the potential to measure and characterise different steel thicknesses by detecting both the elastic, fast-neutron backscatter and the Compton-scattered γ radiations, simultaneously. Further, we demonstrate that the presence of insulation yields a consistent and separable influence on the experimental, wall-thickness measurements. The data from experimental measurements are supported by a comprehensive Monte Carlo computer simulation study.
ABSTRACT
Human mononuclear leukocytes were exposed to microwaves at energies relevant to current public safety recommendations. No detectable effects on viability or function of the leukocytes resulted from exposure to microwaves at specific absorption rates up to 4 milliwatts per milliliter. The results were highly reproducible and provided no evidence that current safety standard recommendations are inappropriate insofar as leukocyte function is concerned.
Subject(s)
Leukocytes/radiation effects , Radio Waves/adverse effects , DNA/biosynthesis , Environmental Exposure , Humans , Maximum Allowable Concentration , Protein Biosynthesis , RNA/biosynthesis , United StatesABSTRACT
Detection of human immunodeficiency virus-type 1 (HIV-1) on only one or a few occasions in infants born to infected mothers has been interpreted to indicate that infection may be transient rather than persistent. Forty-two cases of suspected transient HIV-1 viremia among 1562 perinatally exposed seroreverting infants and one mother were reanalyzed. HIV-1 env sequences were not found in specimens from 20; in specimens from 6, somatic genetic analysis revealed that specimens were mistakenly attributed to an infant; and in specimens from 17, phylogenetic analysis failed to demonstrate the expected linkage between the infant's and the mother's virus. These findings argue that transient HIV-1 infection, if it exists, will only rarely be satisfactorily documented.
Subject(s)
HIV Infections/virology , HIV-1/genetics , HIV-1/isolation & purification , Specimen Handling , DNA, Viral/analysis , DNA, Viral/genetics , Diagnostic Errors , Equipment Contamination , Female , Genes, env , HIV Infections/immunology , HIV Infections/transmission , Humans , Infant , Infant, Newborn , Infectious Disease Transmission, Vertical , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , RNA, Viral/analysis , T-Lymphocytes, Cytotoxic/immunology , Viremia/virologyABSTRACT
BACKGROUND: Brain responses to both food and monetary rewards have been linked to weight gain and obesity in adults, suggesting that general sensitivity to reward contributes to overeating. However, the relationship between brain reward response and body weight in children is unclear. OBJECTIVE: The objective of this study was to assess the brain's response to multiple rewards and the relationship to body weight in children. METHODS: We tested this by performing functional magnetic resonance imaging while children (7- to 11-years-old; healthy weight [n = 31], overweight/obese [n = 30]) played a modified card-guessing task to assess blood-oxygen-level-dependent (BOLD) response to anticipating and winning food and money rewards. Functional magnetic resonance imaging data were analysed using a region of interest and exploratory whole-brain approach. RESULTS: Region of interest results demonstrated increased BOLD response in the striatum to anticipating food vs. neutral (control) and winning money vs. neutral. Whole-brain data showed that winning money vs. food was associated with increased activation in the striatum, as well as regions associated with cognitive control and emotion. Notably, for both approaches, these effects were independent of child weight status. Additionally, children's reported food responsiveness and emotional overeating were negatively correlated with the BOLD response in the left cingulate gyrus for winning food vs. money. CONCLUSION: Overall, findings from this study show that regions associated with reward, cognitive control and emotion may play a role in the brain's response to food and money rewards, independently of how much the child weighs. These findings provide insight into reward sensitivity in children, which may have implications for understanding overeating and the development of obesity.
Subject(s)
Body Weight/physiology , Brain/physiopathology , Feeding Behavior/physiology , Magnetic Resonance Imaging/methods , Pediatric Obesity/physiopathology , Brain/diagnostic imaging , Child , Female , Food , Humans , Male , Reward , Surveys and QuestionnairesABSTRACT
BACKGROUND: To reduce the risk of transmission of meticillin-resistant Staphylococcus aureus (MRSA), international guidelines recommend admission screening to identify hospital patients at risk of colonization. However, routine monitoring indicates that optimum screening compliance levels are not always achieved. In order to enhance compliance, we must better understand those factors which influence staff screening behaviours. AIM: To identify factors which influence staff compliance with hospital MRSA screening policies. METHODS: A sequential two-stage mixed-methods design applied constructs from normalization process theory and the theoretical domains framework to guide data collection and analysis. Initial qualitative findings informed subsequent development of a national cross-sectional survey of nursing staff (N = 450). Multiple regression modelling identified which barriers and enablers best predict staff compliance. FINDINGS: Three factors were significant in predicting optimum (>90%) compliance with MRSA screening: having MRSA screening routinized within the admission process; category of clinical area; feedback of MRSA screening compliance within the clinical area. Integration of data-sets indicated that organizational systems which 'make doing the right thing easy' influence compliance, as does local ward culture. Embedded values and beliefs regarding the relative (de)prioritization of MRSA screening are important. CONCLUSION: To our knowledge, this is the first study to provide original evidence of barriers and enablers to MRSA screening, applying both sociological and psychological theory. As antimicrobial resistance is a global health concern, these findings have international relevance for screening programmes. Future policy recommendations or behaviour change interventions, based on the insights presented here, could have significant impact upon improving screening compliance.
Subject(s)
Diagnostic Tests, Routine/methods , Disease Transmission, Infectious/prevention & control , Guideline Adherence , Mass Screening/methods , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Staphylococcal Infections/diagnosis , Cross-Sectional Studies , Hospitals , HumansABSTRACT
OBJECTIVES: To determine the effects of a nurse led intermediate care programme in patients who have been hospitalised with an acute exacerbation of chronic obstructive pulmonary disease (AECOPD). DESIGN: Randomised controlled trial. SETTING: Community and hospital care in west London. PARTICIPANTS: 122 patients with COPD. INTERVENTION: A care package incorporating initial pulmonary rehabilitation and self-management education, provision of a written, personalised COPD action plan, monthly telephone calls and 3 monthly home visits by a specialist nurse for a period of 2 years. MAIN OUTCOME MEASURE: Hospital readmission rate. SECONDARY OUTCOMES: Unscheduled primary care consultations and quality of life. RESULTS: There were no differences in hospital admission rates or in exacerbation rates between the two groups. Self-management of exacerbations was significantly different and the intervention group were more likely to be treated with oral steroids alone or oral steroids and antibiotics, and the initiators of treatment for exacerbations were statistically more likely to be the patients themselves. 12 patients in the control group died during the 2 year period, eight as a result of COPD, compared with six patients in the intervention group, of whom one died from COPD. This is a significant difference. When the numbers were adjusted to reflect the numbers still alive at 2 years, in the intervention group patients reported a total of 171 unscheduled contacts with their general practitioner (GP) and in the control group, 280 contacts. The number needed to treat was 0.558--ie, for every one COPD patient receiving the intervention and self-management advice, there were 1.79 fewer unscheduled contacts with the GP. CONCLUSIONS: An intermediate care package incorporating pulmonary rehabilitation, self-management education and the receipt of a written COPD action plan, together with regular nurse contact, is associated with a reduced need for unscheduled primary care consultations and a reduction in deaths due to COPD but did not affect the hospital readmission rate.
Subject(s)
Pulmonary Disease, Chronic Obstructive/nursing , Acute Disease , Aged , Community Health Services/economics , Community Health Services/methods , Female , Health Care Costs , Hospitalization/statistics & numerical data , Humans , Male , Patient Education as Topic , Pulmonary Disease, Chronic Obstructive/economics , Pulmonary Disease, Chronic Obstructive/physiopathology , Quality of Life , Spirometry , Steroids/therapeutic use , Tablets , Treatment OutcomeABSTRACT
A HPGe detector has been used to measure the photon spectra from the majority of radionuclide neutron sources in use at NPL (252Cf, 241Am-Be, 241Am-Li, 241Am-B). The HPGe was characterised then modelled to produce a response matrix. The measured pulse height spectra were then unfolded to produce photon fluence spectra. Changes in the photon spectrum with time from a 252Cf source are evident. Spectra from a 2-year-old and 42-year-old 252Cf source are presented showing the change from a continuum to peaks from long-lived isotopes of Cf. Other radionuclide neutron source spectra are also presented and discussed. The new spectra were used to improve the photon to neutron dose equivalent ratios from some earlier work at NPL with GM tubes and EPDs.
Subject(s)
Americium/standards , Beryllium/standards , Californium/standards , Laboratories/standards , Neutrons , Photons , Radiation Monitoring/standards , Americium/analysis , Beryllium/analysis , Calibration , Californium/analysis , Computer Simulation , Monte Carlo Method , Radiation DosageABSTRACT
INTRODUCTION: Pulmonary rehabilitation (PR) is a core component of Chronic Obstructive Pulmonary Disease (COPD) management with well recognized benefits. While suggestions for educational content within pulmonary rehabilitation have been detailed in clinical guidance, it is unclear what educational content is delivered as part of pulmonary rehabilitation, who delivers it, and how it is delivered. METHODS: A systematic review was conducted to identify what educational content is delivered as part of pulmonary rehabilitation, how is this delivered and who delivers it. Databases were searched from 1981 to 2017 using multiple search terms related to "pulmonary rehabilitation" and "education". RESULTS: Fourteen studies were identified. This included 6 survey studies, 5 quasi-experimental studies and 3 RCTs. Five key topics that were consistently included within PR programmes were identified as: 1) Anxiety/depression and stress management. 2) Early recognition of signs of infection. 3) Dyspnea and symptom management. 4) Nutrition. 5) Techniques using inhalers and nebulizers. Broader topics such as welfare/benefits, sexuality, and advance care directives did not frequently feature. Only four studies used tools to measure knowledge or learning pre and post rehabilitation in an attempt to evaluate the effectiveness of the education delivered as part of PR. CONCLUSIONS: The delivery of education in PR programmes is variable and does not follow suggested educational topics. Education needs to take a patient centered motivational approach to ensure effective delivery. Further research into appropriate educational outcome measures are needed, in order to evaluate the changes in behaviour associated with education.
Subject(s)
Delivery of Health Care/methods , Health Education/methods , Pulmonary Disease, Chronic Obstructive/rehabilitation , Databases, Bibliographic , Disease Management , Health Behavior , Humans , Motivation , Patient-Centered Care , Pulmonary Disease, Chronic Obstructive/psychologyABSTRACT
As part of its wide-ranging neutron metrology capabilities, the National Physical Laboratory in the UK has a thermal neutron facility in which accelerator-produced neutrons are moderated within a large assembly or pile of graphite bricks. The neutron field has previously been well characterised in terms of the fluence rate and energy spectrum at various irradiation positions. However, recent changes to the structure (e.g. enlarging the central irradiation cavity) have prompted a renewal and extension of this work. We have also used Monte Carlo modelling to improve our understanding of the pile's performance.
Subject(s)
Laboratories/standards , Monte Carlo Method , Neutrons , Radiation Monitoring/instrumentation , Radiation Protection/instrumentation , Computer Simulation , Equipment Design , Particle Accelerators , Radiation DosageABSTRACT
Human mononuclear leukocytes (MNL) exposed to respiratory syncytial virus (RSV) produce net IL-1 inhibitor bioactivity with the anticipated consequences of cell cycle arrest, suppressed virus-specific proliferation, and reduced expression of activation markers. These studies were undertaken to investigate effects of exposure and resultant net IL-1 inhibitor activity on the expression of the intercellular adhesion molecule-1 (ICAM-1), and its ligand the lymphocyte function-associated antigen (LFA-1). MNL collected at 1, 4, and 24 h after exposure to influenza virus (which induces net IL-1 bioactivity) showed enhanced expression of ICAM-1 and LFA-1 relative to sham-exposed MNL and exhibited cell clustering. In contrast, exposure to RSV was associated with suppressed expression of both ICAM-1 and LFA-1 and with minimal detectable cell clustering throughout the culture period. Influenza virus-exposed MNL produced significantly more IL-1 and IFN-gamma (which require cell-cell collaboration for optimal production) than did RSV-exposed MNL. These data raise the possibility that exposure of MNL to RSV fails to elicit or blocks the early events necessary for cellular collaboration, contributing to early suppression of the clonal expansion of RSV-specific lymphocytes.
Subject(s)
Antigens, CD/biosynthesis , Cell Adhesion Molecules/biosynthesis , Leukocytes, Mononuclear/immunology , Lymphocyte Function-Associated Antigen-1/biosynthesis , Orthomyxoviridae/immunology , Respiratory Syncytial Viruses/immunology , Adult , Cell Communication , Cells, Cultured , Humans , Intercellular Adhesion Molecule-1 , Interferon-gamma/biosynthesis , Interleukin-1/biosynthesis , Leukocytes, Mononuclear/microbiologyABSTRACT
Monocyte and lymphocyte surface-expressed viral antigens have been demonstrated after exposure of unseparated human mononuclear leukocytes to influenza virus in vitro. The current studies, using [35S]methionine pulse-labeled purified preparations of virus-exposed macrophages, depleted of lymphocytes, demonstrate that the presence of these viral proteins does represent new synthesis. However, purified lymphocytes, depleted of monocytes-macrophages and exposed to influenza virus, showed no detectable viral protein synthesis. In further experiments, unseparated mononuclear leukocytes were exposed to virus and subsequently separated by countercurrent centrifugal elutriation. Both macrophages and lymphocytes were then shown to synthesize influenza proteins. Cell-free control or influenza virus-infected macrophage-derived supernatant fluids did not facilitate influenza virus infection of the lymphocytes. The data suggest that macrophages are required for influenza virus infection of human lymphocytes, and raise the possibility that macrophage facilitation of an abortive infection of lymphocytes plays a role in the generation of effective immunity to viral antigens.
Subject(s)
Cell Transformation, Viral , Influenza A virus/genetics , Influenza, Human/blood , Lymphocytes/physiology , Macrophages/physiology , Antigens, Viral/analysis , Humans , Methionine/metabolism , Molecular Weight , Sulfur Radioisotopes , Viral Proteins/biosynthesisABSTRACT
An investigation of the simultaneous unfolding of data from neutron spectrometers using the UMG codes MAXED and GRAVEL has been performed. This approach involves combining the data from the spectrometers before unfolding, thereby performing a single combined unfolding of all the data to yield a final combined spectrum. The study used measured data from three proton recoil counters and also Bonner sphere and proton recoil counter responses calculated from their response functions. In each case, the spectrum derived from combined unfolding is compared with either the spectrum obtained from merging the independently unfolded spectra or the spectrum used to calculate the responses. The advantages and disadvantages of this technique are discussed.