Efficacy of Liver Transplantation in Patients with Primary Biliary Cirrhosis

No controlled trials have been performed to assess the efficacy of liver transplantation. Because of the marked improvement in survival after liver transplantation since 1981, random assignment of patients to a control group not undergoing transplantation is considered clinically inappropriate. To assess the efficacy of liver transplantation in patients with primary biliary cirrhosis, we compared survival in 161 patients with this diagnosis who had undergone a liver transplantation with survival in patients with the same diagnosis who had been treated conservatively. The comparison was performed with use of a recently developed statistical technique, the Mayo model. All patients had undergone liver transplantation between March 1980 and June 1987 and were followed for a median of 25 months. Three months after liver transplantation, the Kaplan–Meier survival probabilities in the recipients were substantially higher than the Mayo-model “simulated-control” survival probabilities (P<0.001). At two years, the Kaplan–Meier survival probability was 0.74, whereas the mean Mayo-model survival probability was 0.31. The patients who were at low risk according to the Mayo model had the best probability of survival after liver transplantation; however, patients at all risk levels who had undergone liver transplantation had higher probabilities of survival than those who had not. We conclude that liver transplantation is an efficacious treatment in patients with advanced primary biliary cirrhosis. (N Engl J Med 1989; 320:1709–13.), LIVER transplantation has been accepted clinically as a lifesaving treatment in various end-stage liver diseases, including primary biliary cirrhosis.1,2 However, no controlled trials have been performed to evaluate the efficacy of this procedure. Indeed, because there has been a marked improvement since 1981 in survival after transplantation, random assignment of patients with advanced liver disease to a nontransplantation control group is considered to be clinically inappropriate. At the Mayo Clinic, a Cox regression model for predicting the probability of survival in patients with conservatively treated primary biliary cirrhosis has been developed.3 To provide control data for assessing the efficacy of…. © 1989, Massachusetts Medical Society. All rights reserved

Age-specific vaccine effectiveness of seasonal 2010/2011 and pandemic influenza A(H1N1) 2009 vaccines in preventing influenza in the United Kingdom

An analysis was undertaken to measure age-specific vaccine effectiveness (VE) of 2010/11 trivalent seasonal influenza vaccine (TIV) and monovalent 2009 pandemic influenza vaccine (PIV) administered in 2009/2010. The test-negative case-control study design was employed based on patients consulting primary care. Overall TIV effectiveness, adjusted for age and month, against confirmed influenza A(H1N1)pdm 2009 infection was 56% (95% CI 42–66); age-specific adjusted VE was 87% (95% CI 45–97) in <5-year-olds and 84% (95% CI 27–97) in 5- to 14-year-olds. Adjusted VE for PIV was only 28% (95% CI x6 to 51) overall and 72% (95% CI 15–91) in <5-year-olds. For confirmed influenza B infection, TIV effectiveness was 57% (95% CI 42–68) and in 5- to 14-year-olds 75% (95% CI 32–91). TIV provided moderate protection against the main circulating strains in 2010/2011, with higher protection in children. PIV administered during the previous season provided residual protection after 1 year, particularly in the <5 years age group

Standing genetic variation and compensatory evolution in transgenic organisms: a growth-enhanced salmon simulation

Genetically modified strains usually are generated within defined genetic backgrounds to minimize variation for the engineered characteristic in order to facilitate basic research investigations or for commercial application. However, interactions between transgenes and genetic background have been documented in both model and commercial agricultural species, indicating that allelic variation at transgene-modifying loci are not uncommon in genomes. Engineered organisms that have the potential to allow entry of transgenes into natural populations may cause changes to ecosystems via the interaction of their specific phenotypes with ecosystem components and services. A transgene introgressing through natural populations is likely to encounter a range of natural genetic variation (among individuals or sub-populations) that could result in changes in phenotype, concomitant with effects on fitness and ecosystem consequences that differ from that seen in the progenitor transgenic strain. In the present study, using a growth hormone transgenic salmon example, we have modeled selection of modifier loci (single and multiple) in the presence of a transgene and have found that accounting for genetic background can significantly affect the persistence of transgenes in populations, potentially reducing or reversing a “Trojan gene” effect. Influences from altered life history characteristics (e.g., developmental timing, age of maturation) and compensatory demographic/ecosystem controls (e.g., density dependence) also were found to have a strong influence on transgene effects. Further, with the presence of a transgene in a population, genetic backgrounds were found to shift in non-transgenic individuals as well, an effect expected to direct phenotypes away from naturally selected optima. The present model has revealed the importance of understanding effects of selection for background genetics on the evolution of phenotypes in populations harbouring transgenes

Surveillance recommendations based on an exploratory analysis of respiratory syncytial virus reports derived from the European Influenza Surveillance System

BACKGROUND: Respiratory syncytial virus (RSV) is an important pathogen that can cause severe illness in infants and young children. In this study, we assessed whether data on RSV collected by the European Influenza Surveillance Scheme (EISS) could be used to build an RSV surveillance system in Europe. METHODS: Influenza and RSV data for the 2002–2003 winter season were analysed for England, France, the Netherlands and Scotland. Data from sentinel physician networks and other sources, mainly hospitals, were collected. Respiratory specimens were tested for influenza and RSV mainly by virus culture and polymerase chain reaction amplification. RESULTS: Data on RSV were entered timely into the EISS database. RSV contributed noticeably to influenza-like illness: in England sentinel RSV detections were common in all age groups, but particularly in young children with 20 (40.8%) of the total number of sentinel swabs testing positive for RSV. Scotland and France also reported the highest percentages of RSV detections in the 0–4 year age group, respectively 10.3% (N = 29) and 12.2% (N = 426). In the Netherlands, RSV was detected in one person aged over 65 years. CONCLUSION: We recommend that respiratory specimens collected in influenza surveillance are also tested systematically for RSV and emphasize the use of both community derived data and data from hospitals for RSV surveillance. RSV data from the EISS have been entered in a timely manner and we consider that the EISS model can be used to develop an RSV surveillance system equivalent to the influenza surveillance in Europe

The costs of respiratory illnesses arising from Florida gulf coast Karenia brevis blooms

This is the final version of the article. Available from NIEHS via the DOI in this recordBACKGROUND: Algal blooms of Karenia brevis, a harmful marine algae, occur almost annually off the west coast of Florida. At high concentrations, K. brevis blooms can cause harm through the release of potent toxins, known as brevetoxins, to the atmosphere. Epidemiologic studies suggest that aerosolized brevetoxins are linked to respiratory illnesses in humans. OBJECTIVES: We hypothesized a relationship between K. brevis blooms and respiratory illness visits to hospital emergency departments (EDs) while controlling for environmental factors, disease, and tourism. We sought to use this relationship to estimate the costs of illness associated with aerosolized brevetoxins. METHODS: We developed a statistical exposure-response model to express hypotheses about the relationship between respiratory illnesses and bloom events. We estimated the model with data on ED visits, K. brevis cell densities, and measures of pollen, pollutants, respiratory disease, and intra-annual population changes. RESULTS: We found that lagged K. brevis cell counts, low air temperatures, influenza outbreaks, high pollen counts, and tourist visits helped explain the number of respiratory-specific ED diagnoses. The capitalized estimated marginal costs of illness for ED respiratory illnesses associated with K. brevis blooms in Sarasota County, Florida, alone ranged from $0.5 to$4 million, depending on bloom severity. CONCLUSIONS: Blooms of K. brevis lead to significant economic impacts. The costs of illness of ED visits are a conservative estimate of the total economic impacts. It will become increasingly necessary to understand the scale of the economic losses associated with K. brevis blooms to make rational choices about appropriate mitigation.This research was sponsored by the Florida Fish & Wildlife Conservation Commission (07182) and the Departments of Environmental Protection and Health; the U.S. Centers for Disease Control and Prevention; the Center for Oceans and Human Health at the Woods Hole Oceanographic Institution [National Science Foundation (NSF) OCE-0430724; National Institute of Environmental Health Sciences (NIEHS) P50 ES012742]; the Ocean and Human Health Center at the University of Miami Rosenstiel School (NSF 0CE0432368; NIEHS 1 P50 ES12736); and the NIEHS (PO1 ES 10594)

An exposure-effect approach for evaluating ecosystem-wide risks from human activities

Ecosystem-based management (EBM) is promoted as the solution for sustainable use. An ecosystem-wide assessment methodology is therefore required. In this paper, we present an approach to assess the risk to ecosystem components from human activities common to marine and coastal ecosystems. We build on: (i) a linkage framework that describes how human activities can impact the ecosystem through pressures, and (ii) a qualitative expert judgement assessment of impact chains describing the exposure and sensitivity of ecological components to those activities. Using case study examples applied at European regional sea scale, we evaluate the risk of an adverse ecological impact from current human activities to a suite of ecological components and, once impacted, the time required for recovery to pre-impact conditions should those activities subside. Grouping impact chains by sectors, pressure type, or ecological components enabled impact risks and recovery times to be identified, supporting resource managers in their efforts to prioritize threats for management, identify most at-risk components, and generate time frames for ecosystem recovery

Mesiodistal root angulation of permanent teeth in children with mixed dentition and normal occlusion

OBJECTIVE: There is little information regarding the mesiodistal angulation of permanent teeth in mixed dentition. The aim of this study was to evaluate mesiodistal root angulation of permanent incisors, canines and first molars of 100 Brazilian children, using a new horizontal reference plane based on the midpoint of the intercuspation of primary canines and permanent first molars in panoramic radiographs during the mixed-dentition phase. MATERIAL AND METHODS: Children were equally divided between the genders with a mean age of 8.9 years (SD=0.76), normal occlusion and no eruptive disturbances. RESULTS: The angulation of the permanent maxillary first molars was close to the vertical, whereas the mandibular molars presented approximately 25 degrees of distal root angulation. The maxillary canines were the most distally angulated teeth, whereas the permanent mandibular canines were vertically positioned. The evaluation of the anterior maxillary area showed vertical position of permanent lateral, and central incisors with a slight distal angulation, whereas the permanent mandibular incisors tended to a mesial radicular convergence. CONCLUSIONS: The proposed reference line could be useful in mixed dentition root angulation evaluation; there was a slight asymmetry in the mesiodistal angulation among homologous teeth, and also a small variation between the male and the female groups, but no difference between 8-and 10-year-old children

Observing response processes with eye tracking in international large-scale assessments: evidence from the OECD PIAAC assessment

This paper reports on a pilot study that used eye tracking techniques to make detailed observations of item response processes in the OECD Programme for the International Assessment of Adult Competencies (PIAAC). The lab-based study also recorded physiological responses using measures of pupil diameter and electrodermal activity. The study tested 14 adult respondents as they individually completed the PIAAC computer-based assessment. The eye tracking observations help to fill an ‘explanatory gap’ by providing data on variation in item response processes that are not captured by other sources of process data such as think aloud protocols or computer-generated log files. The data on fixations and saccades provided detailed information on test item response strategies, enabling profiling of respondent engagement and response processes associated with successful performance. Much of that activity does not include the use of the keyboard and mouse, and involves ‘off-screen’ use of pen and paper (and calculator) that are not captured by assessment log-files. In conclusion, this paper points toward an important application of eye tracking in large-scale assessments. This includes insights into response processes in new domains such as adaptive problem-solving that aim to identify individuals’ ability to select and combine resources from the digital and physical environment