Peter W. Dillingham

Pharmacy-based assessment of adherence to HAART predicts virologic and immunologic treatment response and clinical progression to AIDS and death.

Although adherence to HAART at a level above 95% has been associated with optimal viral suppression, the impact of different levels of adherence on long-term clinical outcomes has not been determined. We used an objective pharmacy-based measure to examine the association between three levels of adherence to HAART and disease progression among a population-based cohort of HIV-infected patients attending an urban HIV specialty clinic. Higher levels of adherence to HAART were significantly associated with longer time to virologic failure (P < 0.001), greater increase in CD4 cell count (P = 0.04), and lower risk of progression to clinical AIDS or death (P < 0.007). After controlling for other factors, patients with low adherence had over five times the risk of disease progression than patients with moderate adherence (P = 0.007) or patients with high adherence (P = 0.001). There was no significant difference in the risk of progression between patients with moderate and high levels of adherence (P > 0.2). Patients who progressed to AIDS or death had significantly higher viral loads (P = 0.01) and lower CD4 cell counts (P = 0.03) than patients who experienced virologic failure, but did not progress.

Primary Care Delivery Is Associated With Greater Physician Experience and Improved Survival Among Persons with AIDS

OBJECTIVE: It has been shown that greater physician experience in the care of persons with AIDS prolongs survival, but how more experienced primary care physicians achieve better outcomes is not known.DESIGN/SETTING/PATIENTS: Retrospective cohort study of HIV-infected patients enrolled in a large staff-model health maintenance organization from 1990 through 1999.MEASUREMENTS: Adjusted odds of medical service delivery and adjusted hazard ratio of death by physician experience level (least, moderate, most) and service utilization.MAIN RESULTS: Primary care delivery by physicians with greater AIDS experience was associated with improved survival. After controlling for disease severity, patients cared for by the most experienced physicians were twice as likely to receive a primary care visit in a given month compared with patients of the least and moderately experienced physicians (P<.01). Patients of the least experienced physicians received the lowest level of outpatient pharmacy and laboratory services (P<.001) and were half as likely to have a specialty care visit compared with patients of the most and moderately experienced physicians (P<.05). Patients who received infrequent primary care visits by the least experienced physicians were 15.3 times more likely to die than patients of the most experienced physicians (P=.02). There was a significant increase in primary care services delivered to the population of HIV-infected patients receiving care in 1999, when highly active antiretroviral therapy (HAART) was in general use, compared with the time period prior to the introduction of HAART.CONCLUSIONS: Primary care delivery by physicians with greater HIV experience contributes to improved patient outcomes.

An update on the interaction between the serotonin transporter promoter variant (5-HTTLPR), stress and depression, plus an exploration of non-confirming findings

In the three years since the most recent meta-analysis of the association between the serotonin transported promoter polymorphism (5-HTTLPR), stress and the development of depression, another 27 studies have been published on this issue, which is an increase of 50% more studies than were previously reviewed. In addition, previous findings of inconsistency of results across studies argued for further exploration of this relationship. From the 81 studies identified to June 2013, the significant relationship between the short form of the 5-HTTLPR was confirmed (p=.0000009), which is stronger than the relationship reported in the most recent meta-analysis in 2011. However, nearly 26% of the 81 studies reviewed failed to show any significant association between the 5-HTTLPR, stress and depression, and four studies found opposite results to those expected. Examination of the methodologies of all studies failed to indicate any flaws in the opposite or unequivocal studies, and the latter had larger sample sizes than those studies which supported the expected association, arguing that the null results were not an outcome of insufficient statistical power. The need to consider aspects of samples and measures of depression, particularly the presence of subtypes of depression in future research is discussed.

Correcting bias in survival estimation resulting from tag failure in acoustic and radiotelemetry studies

The high detection rates of acoustic- and radio-tagged fish greatly improve the ability of an investigator to obtain information on survival and movement of fish with fewer tags. The trade-off, though, is a greater dependence on the individual tag performance, as each tagged fish in a smaller study represents a greater proportion of the outcome. This reduction in release size, due to the increase in detection capability, places a greater emphasis on the need to accurately gauge the status of the tagged fish. Should a tag fail while a smolt is migrating through the study area, the release-recapture model cannot discern the difference between smolt death and tag failure. If the release-recapture models are not adjusted for the probability of tag failure, the estimates of smolt survival will therefore be negatively biased. This article presents a semiparametric approach for adjusting survival estimates from release-recapture studies for tag failure, and provides subsequent estimation of sampling variance and its contributing components.

Electronic Human Immunodeficiency Virus (HIV) Clinical Reminder System Improves Adherence to Practice Guidelines among the University of Washington HIV Study Cohort

We conducted a prospective study of an electronic clinical reminder system in an academic medical center-based human immunodeficiency virus (HIV) specialty clinic. Published performance indicators were used to examine adherence to HIV practice guidelines before and after its implementation for 1204 patients. More than 90% of patients received CD4 cell count and HIV type 1 (HIV-1) RNA level monitoring every 3-6 months during both time periods, and approximately 80% of patients with a CD4 cell count nadir of <350 cells/mm(3) received highly active antiretroviral therapy. Patients were significantly more likely to receive prophylaxis against Mycobacterium avium complex (hazard ratio, 3.84; 95% confidence interval [CI], 1.58-9.31; P=.003), to undergo annual cervical carcinoma screening (OR, 2.09; 95% CI, 1.04-4.16; P=.04), and to undergo serological screening for Toxoplasma gondii (odds ratio [OR], 1.86; 95% CI, 1.05-3.27; P=.03) and syphilis infection (OR, 3.71; 95% CI, 2.37-5.81; P<.0001). HIV clinical reminders delivered at the time that HIV care is provided were associated with more timely initiation of recommended practices.

Evaluating sustainability of fisheries bycatch mortality for marine megafauna: a review of conservation reference points for data-limited populations

Fisheries bycatch threatens populations of marine megafauna such as marine mammals, turtles, seabirds, sharks and rays, but fisheries impacts on non-target populations are often difficult to assess due to factors such as data limitation, poorly defined management objectives and lack of quantitative bycatch reduction targets. Limit reference points can be used to address these issues and thereby facilitate adoption and implementation of mitigation efforts. Reference points based on catch data and life history analysis can identify sustainability limits for bycatch with respect to defined population goals even when data are quite limited. This can expedite assessments for large numbers of species and enable prioritization of management actions based on mitigation urgency and efficacy. This paper reviews limit reference point estimators for marine megafauna bycatch, with the aim of highlighting their utility in fisheries management and promoting best practices for use. Different estimators share a common basic structure that can be flexibly applied to different contexts depending on species life history and available data types. Information on demographic vital rates and abundance is required; of these, abundance is the most data-dependent and thus most limiting factor for application. There are different approaches for handling management risk stemming from uncertainty in reference point and bycatch estimates. Risk tolerance can be incorporated explicitly into the reference point estimator itself, or probability distributions may be used to describe uncertainties in bycatch and reference point estimates, and risk tolerance may guide how those are factored into the management process. Either approach requires simulation-based performance testing such as management strategy evaluation to ensure that management objectives can be achieved. Factoring potential sources of bias into such evaluations is critical. This paper reviews the technical, operational, and political challenges to widespread application of reference points for management of marine megafauna bycatch, while emphasizing the importance of developing assessment frameworks that can facilitate sustainable fishing practices.

Ion selective electrodes in environmental analysis

An overview is given dealing with the application of ion-selective electrodes (ISEs) in environmental analysis. ISEs are placed into the context of the trend of development of sensors for extensive and frequent monitoring. Discussed are the issues such as sensing platforms and their mass-production, improvement of precision, diagnostic of sensor functionality, and development of reference electrodes. Several examples of real-life application of ISEs in environmental analysis are given. The main emphasis of this article is directed towards summarizing recent results of the authors during the past several years.

Drivers of retention and discards of elasmobranch non-target catch

SUMMARY To address growing concern over the effects of fisheries non-target catch on elasmobranchs worldwide, the accurate reporting of elasmobranch catch is essential. This requires data on a combination of measures, including reported landings, retained and discarded non-target catch, and post-discard survival. Identification of the factors influencing discard versus retention is needed to improve catch estimates and to determine wasteful fishing practices. To do this, retention rates of elasmobranch non-target catch in a broad subset of fisheries throughout the world were compared by taxon, fishing country, and gear. A regression tree and random forest analysis indicated that taxon was the most important determinant of retention in this dataset, but all three factors together explained 59% of the variance. Estimates of total elasmobranch removals were calculated by dividing the Food and Agriculture Organization of the United Nations (FAO) global elasmobranch landings by average retention rates, and suggest that total elasmobranch removals may exceed FAO reported landings by as much as 400%. This analysis is the first efforttodirectlycharacterizeglobaldriversofdiscards for elasmobranch non-target catch. The results highlight the importance of accurate quantification of retention and discard rates to improve assessments of the potential impacts of fisheries on these species.

Calculating the variance of the finite rate of population change from a matrix model in Mathematica

Abstract The finite annual rate of population increase ( λ ) is a fundamental demographic parameter that characterizes the relative annual change in animal numbers. Uncertainty in the estimation of λ from demographic population viability analyses (PVAs) has been largely limited to sensitivity analysis, calculating a pseudo-distribution for λ ˆ using Monte Carlo methods, or by use of bootstrap methods. The delta method has been used and suggested by several researchers, but no one has provided the computational means to implement it. In this paper, we present Mathematica code to calculate λ and its variance based on eigenvalue calculations of a Leslie transition matrix. We demonstrate the procedure using data from a Hawaiian hawk ( Buteo solitarius ) study.

The effects of external cues on individual and collective behavior of shoaling fish

We examine changes in interaction rules, predictability, and vigilance of x-ray tetras due to external food and alarm cues. Collective animal behavior is an emergent phenomenon arising from the local interactions of the members of animal groups. Considerable progress has been made in characterizing these interactions, particularly inferring rules that shape and guide the responses of animals to their near neighbors. To date, experimental work has focused on collective behavior within a single, stable context. We examine the individual and collective behavior of a schooling fish species, the x-ray tetra (Pristella maxillaris), identifying their response to changes in context produced by food cues or conspecific alarm cues. Fish exposed to alarm cues show pronounced, broad-ranging changes of behavior, including reducing speed and predictability in their movements. Alarmed fish also alter their responses to other group members, including enacting a smaller zone of repulsion and increasing their frequency of observation of, and responsiveness to, near neighbors. Fish subject to food cues increased speed as a function of neighbor positions and reduced encounter frequency with near neighbors. Overall, changes in individual behavior and the interactions among individuals in response to external cues coincide with changes in group-level patterns, providing insight into the adaptability of behavior to changes in context and interrelationship between local interactions and global patterns in collective behavior.