PD-BAT: A novel approach of pooling basophil donors for expansion of commercial laboratory testing of Chronic Spontaneous Urticaria

The type II autoimmune subtype of Chronic Spontaneous Urticaria (CSU) is characterized by the presence of IgG autoantibodies targeting IgE or the IgE high-affinity receptor (FcεRI) on mast cells and basophils. In evaluation of CSU patients, indirect basophil activation testing (BAT), has been utilized, involving the mixing of patient serum with heterologous peripheral blood donors, followed by flow cytometric assessment of basophil markers. However, the reliability of the indirect BAT results hinges on the quality of the donor basophils utilized. In this study, we introduce an innovative approach where multiple potential basophil donors undergo rigorous BAT characterization alongside control samples. By selecting and pooling donors with optimal performance, we significantly enhance the inter-assay reproducibility of the indirect BAT test.

Viral vector delivered immunogen focuses HIV-1 antibody specificity and increases durability of the circulating antibody recall response

The modestly efficacious HIV-1 vaccine regimen (RV144) conferred 31% vaccine efficacy at 3 years following the four-shot immunization series, coupled with rapid waning of putative immune correlates of decreased infection risk. New strategies to increase magnitude and durability of protective immunity are critically needed. The RV305 HIV-1 clinical trial evaluated the immunological impact of a follow-up boost of HIV-1-uninfected RV144 recipients after 6-8 years with RV144 immunogens (ALVAC-HIV alone, AIDSVAX B/E gp120 alone, or ALVAC-HIV + AIDSVAX B/E gp120). Previous reports demonstrated that this regimen elicited higher binding, antibody Fc function, and cellular responses than the primary RV144 regimen. However, the impact of the canarypox viral vector in driving antibody specificity, breadth, durability and function is unknown. We performed a follow-up analysis of humoral responses elicited in RV305 to determine the impact of the different booster immunogens on HIV-1 epitope specificity, antibody subclass, isotype, and Fc effector functions. Importantly, we observed that the ALVAC vaccine component directly contributed to improved breadth, function, and durability of vaccine-elicited antibody responses. Extended boosts in RV305 increased circulating antibody concentration and coverage of heterologous HIV-1 strains by V1V2-specific antibodies above estimated protective levels observed in RV144. Antibody Fc effector functions, specifically antibody-dependent cellular cytotoxicity and phagocytosis, were boosted to higher levels than was achieved in RV144. V1V2 Env IgG3, a correlate of lower HIV-1 risk, was not increased; plasma Env IgA (specifically IgA1), a correlate of increased HIV-1 risk, was elevated. The quality of the circulating polyclonal antibody response changed with each booster immunization. Remarkably, the ALVAC-HIV booster immunogen induced antibody responses post-second boost, indicating that the viral vector immunogen can be utilized to selectively enhance immune correlates of decreased HIV-1 risk. These results reveal a complex dynamic of HIV-1 immunity post-vaccination that may require careful balancing to achieve protective immunity in the vaccinated population. Trial registration: RV305 clinical trial (ClinicalTrials.gov number, NCT01435135). ClinicalTrials.gov Identifier: NCT00223080.

Randomized, Double-Blind Evaluation of Late Boost Strategies for HIV-Uninfected Vaccine Recipients in the RV144 HIV Vaccine Efficacy Trial

Background

The RV144 ALVAC-HIV prime, AIDSVAX B/E boost afforded 60% efficacy against human immunodeficiency virus (HIV) acquisition at 1 year, waning to 31.2% after 3.5 years. We hypothesized that additional vaccinations might augment immune correlates of protection.

Methods

In a randomized placebo-controlled double-blind study of 162 HIV-negative RV144 vaccine recipients, we evaluated 2 additional boosts, given 6-8 years since RV144 vaccination, for safety and immunogenicity, at weeks 0 and 24. Study groups 1-3 received ALVAC-HIV+AIDSVAX B/E, AIDSVAX B/E, and ALVAC-HIV, respectively, or placebo.

Results

Vaccines were well tolerated. For groups 1 and 2, plasma immunoglobulin (Ig) G, IgA, and neutralizing antibody responses at week 2 were all significantly higher than 2 weeks after the last RV144 vaccination. IgG titers against glycoprotein (gp) 70V1V2 92TH023 increased 14-fold compared with 2 weeks after the last RV144 vaccination (14069 vs 999; P < .001). Groups 1 and 2 did not differ significantly from each other, whereas group 3 was similar to placebo recipients. Responses in groups 1 and 2 declined by week 24 but were boosted by the second vaccination, albeit at lower magnitude than for week 2.

Conclusions

In RV144 vaccinees, AIDSVAX B/E with or without ALVAC-HIV 6-8 years after initial vaccination generated higher humoral responses than after RV144, but these responses were short-lived, and their magnitude did not increase with subsequent boost.

Clinical Trials Registration

NCT01435135.

Reversible Reprogramming of Circulating Memory T Follicular Helper Cell Function during Chronic HIV Infection

Despite the overwhelming benefits of antiretroviral therapy (ART) in curtailing viral load in HIV-infected individuals, ART does not fully restore cellular and humoral immunity. HIV-infected individuals under ART show reduced responses to vaccination and infections and are unable to mount an effective antiviral immune response upon ART cessation. Many factors contribute to these defects, including persistent inflammation, especially in lymphoid tissues, where T follicular helper (Tfh) cells instruct and help B cells launch an effective humoral immune response. In this study we investigated the phenotype and function of circulating memory Tfh cells as a surrogate of Tfh cells in lymph nodes and found significant impairment of this cell population in chronically HIV-infected individuals, leading to reduced B cell responses. We further show that these aberrant memory Tfh cells exhibit an IL-2-responsive gene signature and are more polarized toward a Th1 phenotype. Treatment of functional memory Tfh cells with IL-2 was able to recapitulate the detrimental reprogramming. Importantly, this defect was reversible, as interfering with the IL-2 signaling pathway helped reverse the abnormal differentiation and improved Ab responses. Thus, reversible reprogramming of memory Tfh cells in HIV-infected individuals could be used to enhance Ab responses. Altered microenvironmental conditions in lymphoid tissues leading to altered Tfh cell differentiation could provide one explanation for the poor responsiveness of HIV-infected individuals to new Ags. This explanation has important implications for the development of therapeutic interventions to enhance HIV- and vaccine-mediated Ab responses in patients under ART.

Impact of delirium and suture-less securement on accidental vascular catheter removal in the ICU

The objectives were to describe the incidence of accidental vascular catheter removal (AVCR) in an Australian Intensive Care Unit (ICU) and evaluate whether the fixation method or patient delirium increased the risk of AVCR. This prospective observational study was based in a tertiary level ICU between April 2011 and October 2012. All vascular catheters were secured either by sutures or by a suture-less securement device (STATLOCK(™), Bard Medical, Covington, GA, USA) as per the treating clinician. Data were obtained from bedside nursing staff, with daily screening for delirium completed by the ICU medical team using the Confusion Assessment Method-ICU. 2361 patients were admitted during this period with 1032 patients screened and data available for 322 patients (452 vascular catheters). AVCR occurred in 15 patients (16 vascular catheters) (5.0%) with an incidence of AVCR of 2.77 per 100 catheter-days. Delirious patients were 13-fold more likely to have an AVCR event (odds ratio=13.3; 95% confidence interval 4.36, 40.52; P <0.0001). There was a non-significant trend to an increase in AVCR when using the suture-less securement device (odds ratio=2.6; 95% confidence interval 0.87, 7.8; P=0.09) but delirious patients were no more likely to have an AVCR episode when a suture-less securement device was used (P=0.95). In this study the use of suture-less securement did not seem to increase the risk of AVCR. However, there was a non-significant trend towards increased AVCR when using suture-less securement devices, which may reflect a ß error.

Assessing efficient patient care: should length of stay be calculated independently of local admission rates?

OBJECTIVE

To compare the length of hospitalisation for infants with bronchiolitis across the Eastern region and to assess the impact of the varying admission rates in each hospital.

DESIGN

Data collection through the Hospital Episode Statistics (HES) using the ICD clinical coding for bronchiolitis across all hospitals in east of England for three winter seasons (October to March for the years 2009/10, 2010/11 and 2011/12).

MAIN OUTCOME MEASURE

Length of hospital stay, corrected to adjust for local population.

RESULTS

Seventeen hospitals across the east of England were included in this study. Overall admission rate (as a percentage of the population) for the region was 3.3% and consistent with national data, but rates within individual hospitals varied between 1.5% and 5.7% over the 3-year period. Bed days per 1000 population ('standardised bed days') per year varied almost fourfold, from 34.5 to 122.3 in different hospitals. Corrected length of stay showed high discordance when compared to average length of stay.

CONCLUSIONS

The average length of stay is substantially affected by admission rates, with hospitals who admit a greater proportion of infants appearing to have a shorter uncorrected length of stay. We propose that a single corrected measure for length of stay should be used when assessing the efficiency of care because it is unaffected by variations in local admission rates and is adjusted for local population size.

Effects of Vaginal Estrogens on Serum Estradiol Levels in Postmenopausal Breast Cancer Survivors Taking an Aromatase Inhibitor or a Selective Estrogen Receptor Modulator

Introduction: Intravaginal estradiol (E2) has been proposed as a safe alternative to systemic estrogen therapy. We report serum E2 levels in breast cancer survivors using either vaginal E2 ring (Estring®) or beta E2 tablet (Vagifem®) while also taking an aromatase inhibitor (AI) or selective estrogen receptor modulator (SERM). These patients are compared to a group of breast cancer survivors using an AI but not taking a VE. Patients and Methods: Postmenopausal women with estrogen receptor positive breast cancer (n=24) using an AI or SERM and vaginal estrogens (VE) to control atrophic vaginitis (ring inserted every 90 days; n=10 or 1 tablet inserted 2 x per week; n=14) and 24 control survivors using an AI without VE were enrolled after informed consent. Serum samples were drawn from ring patients pre-insertion and 30 and 60 days post insertion, from tablet patients the morning prior to insertion and 12 hours post insertion, and from controls taking an AI &gt;14 d. Serum samples were assayed for E2 concentrations by highly sensitive radio-immunoassay (Cancer Res 1987;47:1957). Statistical analyses were carried out using SAS® System, v. 9.2. Results: Patient data are provided in tables 1 and 2 (control data not shown). Circulating E2 levels pre-insertion in tablet patients were not significantly different than those in control patients (mean difference=4.7 pmol/l SD:3.2; CI: 2.9-4.9, p=0.48). E2 levels pre-insertion in patients using the ring were significantly greater than controls (mean difference=14.2 pmol/l; SD:7.2;CI, 11-19:p=0.0001). In tablet patients, E2 levels at 12 hours post insertion were 76 pmol/l higher than at pre-insertion baseline (SD:97; CI, 14-89, p&lt;0.0001), and E2 levels at 12 weeks post insertion in ring patients were 30 pmol/l higher than at pre-insertion baseline(SD:50; CI: 10-20, p=0.001). Discussion: Our data did not show a significant difference in pre-insertion E2 levels for the tablet compared to controls, but we did observe a significant difference in pre-insertion E2 levels for the ring compared to controls. Importantly, we also observed a significant elevation in E2 levels in most patients using VEs post insertion, regardless of the type of device (tablet or ring). The clinical significance of vaginal E2 absorption is unknown, although elevated E2 levels are diametrically opposite of the desired effect for breast cancer patients taking an AI. Vaginal estrogen in patients receiving an adjuvant AI must be advised with caution.ID#SERM/AIPRE-INSERTION PMOL/LPOST-INSERTION PMOL/LMONTHS ON TABLETV4T4.61424V10T35.449V13TIS193V14T1330813V2L4.91912V9L&lt;3.01938V11L&lt;3.01318V5E105773V1A&lt;3.01912V3A&lt;3.0&lt;3.014V6A&lt;3.08918V7A&lt;3.03348V8A5.322936V12A&lt;3.06113IS=Insufficient sample; A=anastrozole; L=letrozole; E=exemestane; T=tamoxifen; R=raloxifeneTable 2. Cases on VE E2 Ring and AI or SERMID #SERM/AIPRE-INSERTION PMOL/L30 DAYS PMOL/L60 DAYS PMOL/LMONTHS ON RINGE6T25222015E9T11169.815E10T15201712E8R18151412E4L19161512E5L&lt;3.0&lt;3.0&lt;3.09E7L&lt;3.0&lt;3.0&lt;3.054E1A121071693E2A1511116E3A2131356 

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 806.

US nephrologists' recommendation of dialysis modality: results of a national survey

Selection of a dialysis modality for persons with end-stage renal disease (ESRD) has important lifestyle and occupational implications. The factors affecting modality choice remain unclear, resulting in a low rate of peritoneal dialysis (PD) in the United States compared with other countries. A national survey of 271 US nephrologists was conducted from June 1997 to June 1998 to assess the relative importance of nonclinical and clinical factors related to dialysis modality selection for patients with ESRD. Hypothetical patient scenarios were randomly assigned to nephrologists to determine their recommendation for dialytic therapy based on patient demographic, clinical, and social factors. US nephrologists were more likely to recommend PD for men with ESRD compared with women (39% versus 33%; P: < 0.05; adjusted odds ratio, 1.44; 95% confidence interval, 1.15 to 1.80), as well as for patients with good compliance (adjusted odds ratio, 11.80; 95% confidence interval, 9.29 to 15.01), weight less than 200 lb (adjusted odds ratio, 2.3; 95% confidence interval, 1.8 to 2.9), residual renal function (adjusted odds ratio, 2.14; 95% confidence interval, 1.71 to 2.70), absence of diabetes (adjusted odds ratio, 2.0; 95% confidence interval, 1.6 to 2.5), and living with family (adjusted odds ratio, 1.7; 95% confidence interval, 1.4 to 2.1). Nephrologists in practice for 11 or more years were less likely to recommend PD. The association of male sex with PD therapy suggests a potential bias or sensitivity to women's perception of body image. Race was not associated with PD recommendations after controlling for other demographic and clinical characteristics. Because the incident US ESRD population is increasingly characterized by factors associated with not selecting PD (diabetes, obesity, malnourishment, living alone, and substance abuse problems), our results suggest that PD use may decrease over time.

Tertiary Normal Faulting in the Canyon Range, Eastern Sevier Desert

The contact between pre-Mesozoic and Tertiary rocks in the western Canyon Range, west-central Utah, has been interpreted as a large, low-angle normal fault that marks the breakaway zone of the hypothesized, basin-forming Sevier Desert detachment. Recent fieldwork suggests that the contact may in fact be depositional along much or all of its length. Deformational fabric in the supposed footwall likely traces to the Mesozoic Sevier orogeny rather than to Tertiary detachment faulting. Kinematic indicators at the range front are not generally consistent with low-angle normal-fault motion; instead, well-exposed high-angle faults are the dominant range-bounding structures. The Tertiary conglomerates of the western Canyon Range foothills, previously viewed as an evolving syntectonic deposit related to detachment faulting, are here reinterpreted as three distinct units that reflect different periods and tectonic settings. The pattern in these conglomerates, and in fault-offset gravity-slide deposits that mantle the western foothills, is consistent with block faulting and rotation along several generations of high-angle structures. Local seismic-reflection data lend qualitative support to this interpretation, and underscore the need to consider alternative working hypotheses for evolution of the Sevier Desert basin.

Preference values for visual states in patients planning to undergo cataract surgery

To assess how preference values that cataract surgery patients assign to their preoperative visual states relate to visual acuity and problems in specific aspects of daily life, the authors interviewed 47 patients scheduled to have cataract surgery. Using a rating-scale technique with a scale from 0 (death) to 1 (excellent health), the patients had a mean preference value of 0.68 for their preoperative vision. Patients' preference values for their preoperative vision were more closely related to problems in specific aspects of daily life (especially feelings of depression and problems interacting with people) than to visual acuity in the operative eye, better eye, or worse eye, or a weighted average of visual acuities in both eyes. These results provide a rationale for relying more on patients' views about the effects of visual impairment than on measures of visual acuity when assessing the need for cataract surgery.

National survey of Clerkship Directors in Internal Medicine on the competencies that should be addressed in the medicine core clerkship

PURPOSE

To prioritize competencies that should be addressed in the medicine core clerkship, assess factors influencing this prioritization, and estimate the percentage of clerkship time that should be devoted to inpatient versus outpatient care.

METHODS

A national survey of the Clerkship Directors in Internal Medicine (CDIM) was used. Using explicit criteria, respondents assigned priority scores, on a 1 to 5 scale, to 17 general competencies and 60 disease-specific clinical competencies pertinent to care of adult patients in inpatient. ambulatory, intensive care, and emergency settings.

RESULTS

Ninety-three (75%) of 124 CDIM members responded. The highest mean priority scores were assigned to 6 general competencies: case presentation skills (4.65), diagnostic decision-making (4.64), history and physical diagnosis (4.61), test interpretation (4.47), communication with patients (4.35), and therapeutic decision-making (4.12). Disease-specific clinical competency areas receiving the highest mean priority scores were: hypertension (4.57), coronary disease (4.53), diabetes mellitus (4.45), heart failure (4.42), pneumonia (4.39), chronic obstructive pulmonary disease (4.26), acid-base/electrolyte disorders (4.19), and acute chest pain (4.08). Priorities for general competencies were moderately correlated with importance to the practice of general internists (mean Spearman rho 0.49) and with importance to students pursuing careers outside internal medicine (mean Spearman rho 0.45), but only weakly correlated with the adequacy with which a competency was addressed in other parts of the curriculum. Respondents' mean recommended allocation of clerkship time was: 52% inpatient, 33% ambulatory care, 8% intensive care, and 7% emergency medicine. This time allocation did not differ by any characteristics of respondents.

CONCLUSION

There is consensus among medicine clerkship directors that the medicine core clerkship should emphasize fundamental competencies and devote at least one third of the time to clinical competencies pertinent to ambulatory care.

Parallelized formulation of the maximum likelihood-expectation maximization algorithm for fine-grain message-passing architectures

Recent architectural and technological advances have led to the feasibility of a new class of massively parallel processing systems based on a fine-grain, message-passing computational model. These machines provide a new alternative for the development of fast, cost-efficient Maximum Likelihood-Expectation Maximization (ML-EM) algorithmic formulations. As an important first step in determining the potential performance benefits to be gathered from such formulations, we have developed an ML-EM algorithm suitable for the high-communications, low-memory (HCLM) execution model supported by this new class of machines. Evaluation of this algorithm indicates a normalized least-square error comparable to, or better than, that obtained via a sequential ray-driven ML-EM formulation and an effective speedup in execution time (as determined via discrete-event simulation of the Pica multiprocessor system currently under development at the Georgia Institute of Technology) of well over two orders of magnitude compared to current ray-driven sequential ML-EM formulations on high-end workstations. Thus, the HCLM algorithmic formulation may provide ML-EM reconstructions within clinical time-frames.