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Objectives: This study investigated the relationship between on-field, objective signs immediately following sport-related concussion and self-reported symptom endorsement within 1 day post injury. Methods: A retrospective case series of 237 concussed high school athletes was performed. On-field signs were evaluated immediately post injury. Self-reported symptoms (2 clusters) were collected within 1 day post injury. A two-step structural equation model and follow-up bivariate regression analyses of significant on-field signs and symptom clusters were performed. Results: Signs of immediate memory, β=0.20, p=.04, and postural instability, β=0.19, p < .01, significantly predicted a greater likelihood of endorsing the cognitive-migraine-fatigue symptom cluster within 1 day post injury. Regarding signs correlated with specific symptoms, immediate memory was associated with symptoms of trouble remembering, χ2=37.92, p < .001, odds ratio (OR)=3.89 (95% confidence interval (CI) [2.47, 6.13]), and concentration difficulties, χ2=10.84, p=.001, OR=2.13 (95% CI [1.37, 3.30]). Postural instability was associated with symptom endorsement of trouble remembering, χ2=12.08, p < .001, OR=1.76 (95% CI [1.29, 2.40]). Conclusions: Certain post-concussion on-field signs exhibited after injury were associated with specific symptom endorsement within 1 day post injury. Based on these associations, individualized education-based interventions and academic accommodations may help reduce unanticipated worry from parents, students, and teachers following a student-athlete’s sport-related concussion, especially in cases of delayed onset symptoms. (JINS, 2018, 24, 476–485)
To determine whether increases in contact isolation precautions are associated with decreased adherence to isolation practices among healthcare workers (HCWs).
Prospective cohort study from February 2009 to October 2009.
Eleven teaching hospitals.
One thousand thirteen observations conducted on HCWs. Additional data included the number of persons in isolation, types of HCWs, and hospital-specific contact precaution practices. Main outcome measures included compliance with individual components of contact isolation precautions (hand hygiene before and after patient encounter, donning of gown and glove upon entering a patient room, and doffing upon exiting) and overall compliance (all 5 measures together) during varying burdens of isolation.
Compliance with hand hygiene was as follows: prior to donning gowns/gloves, 37.2%; gowning, 74.3%; gloving, 80.1%; doffing of gowns/gloves, 80.1%; after gown/glove removal, 61%. Compliance with all components was 28.9%. As the burden of isolation increased (20% or less to greater than 60%), a decrease in compliance with hand hygiene (43.6%—4.9%) and with all 5 components (31.5%—6.5%) was observed. In multivariable analysis, there was an increase in noncompliance with all 5 components of the contact isolation precautions bundle (odds ratio [OR], 6.6 [95% confidence interval (CI), 1.15-37.44]; P = .03) and in noncompliance with hand hygiene prior to donning gowns and gloves (OR, 10.1 [95% CI, 1.84—55.54]; P = .008) associated with increasing burden of isolation.
As the proportion of patients in contact isolation increases, compliance with contact isolation precautions decreases. Placing 40% of patients under contact precautions represents a tipping point for noncompliance with contact isolation precautions measures.
Fetal growth restriction is a risk factor for development of adulthood diseases, but the biological mechanism of this association remains unknown. Limited biomarkers have been studied in settings of preterm birth and maternal inflammation, but the relationship between a wide range of immune biomarkers and fetal growth has not been studied. The hypothesis of this study was that fetal growth restriction is associated with altered immune biomarker levels. We examined the relationship between small for gestational age (SGA) status and 27 umbilical cord blood immune biomarkers. This study was part of a large-scale cohort study of preterm birth and low birth weight conducted at Boston Medical Center, an inner city, predominantly minority patient population. Growth status was determined based on birth weight standardized to an internal reference. There were 74 SGA births and 319 appropriate for age (AGA) births with complete clinical and biomarker data. Adjusting for covariates and using AGA as reference, SGA births had lower levels of log IL-1β (ng/l; β −0.38, 95% CI −0.57, −0.19, P < 0.01), log BDNF (β −0.29, 95% CI −0.55, −0.03, P < 0.05) and log NT-3 (β −0.46, 95% CI −0.77, −0.15, P < 0.01). No associations were found between other biomarkers and SGA. In conclusion, three biomarkers were selectively associated with SGA status. Our results provide information that could be used to guide additional studied aimed at determining mechanisms that contribute to fetal growth.
Defining the causal relationship between a microbe and encephalitis is complex. Over 100 different infectious agents may cause encephalitis, often as one of the rarer manifestations of infection. The gold-standard techniques to detect causative infectious agents in encephalitis in life depend on the study of brain biopsy material; however, in most cases this is not possible. We present the UK perspective on aetiological case definitions for acute encephalitis and extend them to include immune-mediated causes. Expert opinion was primarily used and was supplemented by literature-based methods. Wide usage of these definitions will facilitate comparison between studies and result in a better understanding of the causes of this devastating condition. They provide a framework for regular review and updating as the knowledge base increases both clinically and through improvements in diagnostic methods. The importance of new and emerging pathogens as causes of encephalitis can be assessed against the principles laid out here.
Tight binaries discovered in young nearby associations are ideal targets to provide dynamical mass measurments through orbital monitoring. Coupled with estimated temperatures, surface gravities and luminosities, direct mass measurments provide benchmarks for evolutionary models of low-mass stars (M ≤ 0.5 M๏) and brown dwarfs (M ≤ 0.078 M๏) at young ages (Age ≤ 100 Myrs).
TWA22 AB is likely to be a member of the nearby TW Hydrae association (Age ~ 8 Myr). It was resolved in a tigh binary with a projected separation of a few AU. In this paper we present preliminary results on the companion orbital monitoring and on the spectral characterisation of the system.
On 29 April 2009, an imported case of pandemic (H1N1) 2009 virus infection was detected in a London school. As further cases, pupils and staff members were identified, school closure and mass prophylaxis were implemented. An observational descriptive study was conducted to provide an insight into the clinical presentation and transmission dynamics in this setting. Between 15 April and 15 May 2009, 91 symptomatic cases were identified: 33 were confirmed positive for pandemic (H1N1) 2009 virus infection; 57 were tested negative; in one the results were unavailable. Transmission occurred first within the school, and subsequently outside. Attack rates were 2% in pupils (15% in the 11–12 years age group) and 17% in household contacts. The predominant symptoms were fever (97%), respiratory symptoms (91%), and sore throat (79%). Limited spread in the school may have been due to a combination of school closure and mass prophylaxis. However, transmission continued through household contacts to other schools.
By 2007 more than half of the world's population is expected to reside in cities (United Nations,2004). As urban populations and the number of cities expand, natural and agricultural lands are transformed into highly altered landscapes. These changes in demography and land use have contributed to the alteration of biogeochemical cycles at local, regional and global scales (Vitousek et al., 1997a; Pouyat et al., 2003). Yet we lack sufficient data with which to assess the underlying mechanisms of land-use change (Groffman et al., 2004), largely because of the difficulty encountered when applying established biogeochemical research methods such as large-scale field manipulations to urban and suburban ecosystems (Pouyat et al., 1995a). Moreover, current conceptual and quantitative biogeochemical models incorporate human effects only indirectly (Groffman and Likens, 1994).
As a result, most urban ecosystem studies have relied on a comparative approach or ‘natural experiments’ to investigate urban effects on biogeochemical cycles in ecological remnants characteristic of a particular area or region (Pickett et al., 2001). This approach takes advantage of remnant systems as ‘whole ecosystem’ manipulations by which the effects of multiple urban stress and disturbance factors are assessed with established statistical methods and modelling approaches (Pouyat et al., 1995a; Breitburg et al., 1998; Carreiro and Tripler, 2005; Carreiro et al., Chapter 19).
Twenty-three strains of rhinovirus were isolated from 102 patients who had common colds on arrival at a Royal Air Force recruit centre during a 6-month period from June to November, 1960. Three of these strains were M type rhino-viruses similar to ECHO 28 virus. Twenty strains were H type rhinoviruses which fell into six or more different antigenic types. Two of these types were similar to the prototypes Sal/1/58/H and Sheffield/1/60/H. Three types were antigenically distinct from those previously reported in this country and several strains are still unclassified. Other human respiratory viruses were not isolated from common colds occurring at this time among the population studied.
We are indebted to the Senior Medical Officer of R.A.F. Cardington for providing facilities for the investigation, to Squadron Leader M. Shearer for his help in collecting convalescent blood specimens, and to the Director-General of the Royal Air Force Medical Service for permission to publish this paper.
We wish to acknowledge the excellent technical assistance of Miss Ann Deacon. We should also like to thank Dr H. E. M. Kay of the Royal Marsden Hospital for supplying human embryo kidney.
Thirty-three of 72 heroin addicts attending a recognized clinic for drug addition had a history of jaundice, but in only five was the serum positive for hepatitis-associated antigen (HAA) when examined by immunodiffusion, immunoelectro-osmophoresis and complement fixation. Two of these were repeatedly positive over an 8–12 month follow-up period and liver biopsy showed chronic persistent hepatitis. A third later developed acute hepatitis. A study of the injection habits suggested that the present low incidence of HAA and the decrease in number of cases with jaundice was probably related to the provision of free disposable syringes by the clinic since it was opened in 1968.
An approach is developed to study the dynamics of protein conformational transitions in depth. A computational (Monte Carlo) approach based on a united residue model is used. Unbiased transitions between the Apo and Holo conformations/states of calmodulin are observed at the rate of 1 per day per processor. A series of models of increasing complexity is studied, accounting for hydrophobic interactions and calcium binding. Details of the transitional region and structural information about intermediate states are obtained. Statistically converged ensembles of transitions are obtained in a reasonable real time period.
Background. Infectious mononucleosis (IM) is a risk factor for chronic fatigue. Reduced activity is the most consistent factor found to be associated with poor outcome following the onset of infectious mononucleosis. However, little is known about the biological mechanisms involved in the pathogenesis of chronic fatigue following IM and no study, so far, has examined the relation between certain illness beliefs and poor outcome. This study explored immunological, endocrine, behavioural and cognitive responses to the acute illness and assessed which components of these groups of risk factors predicted a chronic course.
Method. Using a prospective cohort design, 71 primary care patients with IM were enrolled onto the study and interviewed. Their recovery was explored by postal questionnaire up to 1 year later.
Results. In the univariate analysis, increased baseline levels of immune activation were associated with fatigue at baseline and 3 months. Cortisol levels were not associated with fatigue at any point. Using multivariate models of clinical and psychosocial baseline factors, severity of symptoms and illness perceptions were found to predict fatigue 3 months later. At 6 months, fatigue was best predicted by female gender and illness perceptions, and at 12 months by female gender and a symptoms–disability factor.
Conclusions. In the multivariate analysis no factors were found to predict poor outcome at all time-points. Instead the pattern of predictors changed over time, partly but not completely consistent with our a priori predictions. Larger studies are needed to explore further the predictive nature of biopsychosocial factors in the pathogenesis of chronic fatigue related to IM. The psycho-behavioural predictors found in this study are amenable to intervention. Such interventions should be tested in randomized controlled trials.
We present preliminary results from a deep near-infrared J-band and I-band photometric survey of the Pleiades for freely-floating superplanets and brown dwarfs (BD) near the deuterium burning limit (DBL). With limiting magnitudes of J=20.5 and I=23.5, we have selected candidate Pleiads on the basis of evolutionary tracks, color-magnitudes, and I-J color lower limits (non-detections at deep I-band). Likelihoods of membership will be ultimately determined by a combination of image profile analysis, spectral energy distribution, proper motion, and low-resolution measurements of near-infrared water and/or methane absorption slopes. If confirmed, our faintest candidates are predicted to have made the transition from L to T spectral types with temperatures down to 820 K, and masses approaching 10 MJup.
Five major hepatotrophic viruses causing acute or chronic viral hepatitis have been identified. The viruses causing types A to E have been extensively characterized; other viruses, including Epstein-Barr virus and cytomegalovirus may also cause hepatitis. A giant cell hepatitis, and fulminant hepatitis (Fagan et al., 1989; Phillips et al., 1991), for which viruses are being sought, are recognised. Although the molecular virology and serological response in viral hepatitis have been studied in depth, the immune response to hepatitis A to E remains complex. The immunobiology of type B hepatitis has been most widely studied.
Hepatitis A virus (HAV) has a similar particle size, capsid structure and genome organisation to other picornoviruses, but is sufficiently different to be classified as a genus within the picornovirus family. The genomes of several strains of HAV have been sequenced and found to be 7470–7478 nucleotides (nt) in length. Type A hepatitis is spread predominantly by the faecal-oral route, but parenteral transmission has been described. Clinical disease with jaundice is uncommon in infants and young children and the infection may pass unnoticed in this group. Severe hepatitis is correspondingly more common in older persons. In countries where there has been improvement in socio-economic conditions and sanitation, such as southern Europe and China, there has been an increase in the mean age of infection.
There is a high level of conservation of cDNA of human HAV strains at the nucleotide level, but PCR based partial sequencing of regions of HAV has revealed unexpected genetic diversity.
The azole antifungal agents represent a major advance in the management of superficial and systemic fungal infections. Itraconazole appears to have a broad spectrum of in vitro activity and is the first azole antifungal agent to have activity against Aspergillus species. Itraconazole acts primarily by impairing the synthesis of ergosterol, resulting in a defective fungal cell membrane with altered permeability and function. It is effective for a wide variety of mycotic infections and some fungal meningeal infections. Most adverse effects have been relatively minor and do not lead to discontinuation of therapy.
Our study examines a stochastic R&D model with flexible termination time and without rivalry. Specifically, we assume a stochastic relationship between expenditures rate and the project's status. Furthermore, the termination time of the project is incorporated into the R&D model as a decision variable by allowing the controller to ‘sell' the obtained technology from the project at any point of time. The proposed framework extends the classical approach in the R&D literature.
The main purpose of our study is to determine the optimal stopping time of the project and to characterize qualitatively the firm's expenditure strategy. We show that under certain realistic conditions, the optimal stopping strategy is a control limit policy. Furthermore, the research effort increases monotonically over the development time of the project.