Temporal evolution of new T1-weighted hypo-intense lesions and central brain atrophy in patients with a first clinical demyelinating event treated with subcutaneous interferon β-1a

OBJECTIVE

Evaluate the effect of subcutaneous interferon β-1a (sc IFN β-1a) versus placebo on the evolution of T1-weighted MRI lesions and central brain atrophy in in patients with a first clinical demyelinating event (FCDE).

METHODS

Post hoc analysis of baseline-to-24 month MRI data from patients with an FCDE who received sc IFN β-1a 44 μg once- (qw) or three-times-weekly (tiw), or placebo, in REFLEX. Patients were grouped according to treatment regimen or conversion to clinically definite MS (CDMS) status. The intensity of new lesions on unenhanced T1-weighted images was classified as T1 iso- or hypo-intense (black holes) and percentage ventricular volume change (PVVC) was assessed throughout the study.

RESULTS

In patients not converting to CDMS, sc IFN β-1a tiw or qw, versus placebo, reduced the overall number of new lesions (P < 0.001 and P = 0.005) and new T1 iso-intense lesions (P < 0.001 and P = 0.002) after 24 months; only sc IFN β-1a tiw was associated with fewer T1 hypo-intense lesions versus placebo (P < 0.001). PVVC findings in patients treated with sc IFN β-1a suggested pseudo-atrophy that was ~ fivefold greater versus placebo in the first year of treatment (placebo 1.11%; qw 4.28%; tiw 6.76%; P < 001); similar findings were apparent for non-converting patients.

CONCLUSIONS

In patients with an FCDE, treatment with sc IFN β-1a tiw for 24 months reduced the number of new lesions evolving into black holes.

Using longitudinal survey and sensor data to understand the social and ecological determinants of clean fuels use and discontinuance in rural Ghana

Efforts to reduce the health and ecological burdens of household biomass combustion are underway in Ghana, principally by promoting clean cookstoves and fuels. Recent studies have focused on the sustained use of clean cookstoves, but sometimes household adopt a new cookstove and then end use of that stove. In this study, we introduce a novel framework for understanding and encouraging household transitions to cleaner cooking: clean fuel discontinuance. We leveraged data from the Ghana Randomized Air Pollution and Health Study (GRAPHS) (N = 1412) where pregnant women received either improved biomass (BioLite) or dual burner LPG stoves for free. LPG users were given free LPG refills during GRAPHS. Weekly questionnaires were administered. Stove use monitors tracked a sub-cohort (n = 220) 6 months before and after the fuel subsidy. We examined social and ecological determinants of stove use and discontinuance. Overall intervention stove use adherence was high throughout GRAPHS, with self-reported use at 69% and 86% of participant-weeks for BioLite and LPG arms respectively. Participants used intervention stoves less for meals requiring vigorous stirring. Burns from intervention stoves decreased use among BioLite (RR: 0.96, p = 0.009), but not LPG users. Device breakage was mentioned as an impediment in 18% of free-text responses for LPG users and 1% for BioLite. Tree canopy within a spatial buffer-a plausible proxy for biomass fuels access-was the only variable explaining LPG discontinued stove use in adjusted Cox time-to-event analyses (HR = -0.56, p < 0.001). Future studies should consider the stove use discontinuance framework.

Deliberating performance targets workshop: Potential paths for emerging PM2.5 and O3 air sensor progress

The United States Environmental Protection Agency held an international two-day workshop in June 2018 to deliberate possible performance targets for non-regulatory fine particulate matter (PM_2.5) and ozone (O₃) air sensors. The need for a workshop arose from the lack of any market-wide manufacturer requirement for Ozone documented sensor performance evaluations, the lack of any independent third party or government-based sensor performance certification program, and uncertainty among all users as to the general usability of air sensor data. A multi-sector subject matter expert panel was assembled to facilitate an open discussion on these issues with multiple stakeholders. This summary provides an overview of the workshop purpose, key findings from the deliberations, and considerations for future actions specific to sensors. Important findings concerning PM_2.5 and O₃ sensors included the lack of consistent performance indicators and statistical metrics as well as highly variable data quality requirements depending on the intended use. While the workshop did not attempt to yield consensus on any topic, a key message was that a number of possible future actions would be beneficial to all stakeholders regarding sensor technologies. These included documentation of best practices, sharing quality assurance results along with sensor data, and the development of a common performance target lexicon, performance targets, and test protocols.

High sensitivity troponin T provides useful prognostic information in non-acute chest pain

OBJECTIVE

To evaluate the prognostic value of high-sensitivity troponin T (hs-cTnT) in patients who present to General Practitioners (GPs) with non-acute chest pain.

DESIGN, SETTING AND PATIENTS

A total of 625 patients who were referred by their GPs to a regional Rapid Access Chest Pain Clinic in Tayside, Scotland were consented and recruited. Diamond-Forrester pretest probability of coronary artery disease (CAD) was used to select patients with intermediate and high-pretest probability. Hs-cTnT and B-type Natriuretic Peptide (BNP) were measured and final diagnosis recorded. Twelve-month follow-up for cardiac events and hospital admission data was collected. Sensitivity, specificity, positive predictive value and negative predictive value (NPV), for both prognosis and diagnosis, were produced using various pre-specified cut-off values for hs-cTnT and BNP.

RESULTS

A total of 579 patients were included in the final analysis. Of these, 477 had intermediate/high-pretest probability of CAD. A total of 431 (90.4%) of patients had a hs-cTnT ≤14 ng/l. In this study, hs-cTnT of 14 ng/l was the best cut-off for ruling out if a patient would have an admission for cardiac chest pain in the following 12 months (specificity 90%, NPV 91.4%). It performed well as a predictor of a subsequent negative diagnosis of cardiac chest pain with a specificity of 92.4% and NPV of 83.5%.

CONCLUSIONS

Hs-cTnT, at the same level currently used in clinical practice as a diagnostic cut-off for myocardial infarction and acute coronary syndromes, is also a clinically-meaningful indicator for further 12-month cardiac chest pain hospital admissions in patients with non-acute chest pain referred to chest pain clinics by GPs.

Indacaterol once-daily is equally effective dosed in the evening or morning in COPD

Indacaterol is a novel, inhaled, long-acting β(2)-agonist providing 24-h bronchodilation with once-daily (o.d.) dosing in patients with COPD. In this double-blind, incomplete block crossover study, patients with moderate-to-severe COPD were randomised to receive three treatment cycles from: indacaterol 300 μg o.d. dosed PM or AM, salmeterol 50 μg twice daily or placebo, each for 14 days. Trough FEV(1) was measured 24 h after indacaterol, and 12 h after salmeterol. Ninety-six patients (mean age: 64 years; post-bronchodilator FEV(1) 57% predicted, FEV(1)/FVC 55%) were randomised; 83 completed. After 14 days, the difference vs. placebo in trough FEV(1) for PM indacaterol was 200 mL (p < 0.001 [primary analysis]) and for AM indacaterol was 200 mL (p < 0.001). Compared with salmeterol, trough FEV(1) for PM indacaterol was 110 mL higher (p < 0.001), and for AM indacaterol was 50 mL higher (p = NS). Over 14 days, vs. placebo, both PM and AM indacaterol improved the % of nights with no awakenings (by 11.9 and 8.1 points; p < 0.01); the % of days with no daytime symptoms (by 6.7 and 5.5 points; p < 0.05); and the % of days able to perform usual activities (by 6.7 and 7.8 points; p < 0.05). Indacaterol provided 24-h bronchodilation and improvement in symptoms regardless of whether taken regularly in the morning or evening.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT00615030.

Evaluation of light transmission and distribution materials for Lunar and Martian bioregenerative life support

The materials that were selected and evaluated in this study in the context of bioregenerative advanced life support included polymer optical cables, for transmission of photosynthetic photon flux (PPF), and light pipe, woven optical pad and light-emitting fiber (LEF) for PPF distribution. All materials exhibited significant fidelity in transmitting the spectral characteristics of the artificial lluminator's Xenon-Metal Halide lamp. The PPF attenuation values for the polymer cables EL-200, EL-300, EL-400, and EL-500 were not significantly distinguishable from one another nor from that of the fused-silica cable of 0.34 dB/m. With the exception of EL-100 and EL-700, which had significantly lower PPF transmission efficiencies of 54.9%/m and 66.6%/m, respectively, all the other polymer cables had PPF transmission efficiencies of over 85%/m which, except for EL-300, were not significantly different from one another nor from that of the fused-silica cable of 93.2%/m. The highest PPF output efficiency achieved for the 7.1-cm light pipe 14.7%, for its maximum pipe length of 100 cm. At a constant pipe length of 50 cm, the PPF output efficiency of the 10-cm light pipe of 0.71% was significantly lower than that of the 7.1-cm light pipe of 10.54%. The PPF output for the woven optical pad was determined to be 36.3%. The PPF output efficiency for the LEF without the optic fastener was determined to be 27.1%, whereas that for the LEF with the optic fastener was 50.3%, that is, the maximum value of PPF output efficiency in the study. The polymer optical cables, light pipe, woven optical pad, and LEF exhibited significant regularity and symmetry in their PPF output spatial distributions.

Stiff competition expected in ED market

At the British Association of Urological Surgeons Annual Meeting, held June 2529, 2001, in Dublin, Ireland, participants gathered to absorb the newest information regarding treatment strategies, as well as the latest procedures and new developments in equipment.

Virtual reality-enhanced stroke rehabilitation

A personal computer (PC)-based desktop virtual reality (VR) system was developed for rehabilitating hand function in stroke patients. The system uses two input devices, a CyberGlove and a Rutgers Master II-ND (RMII) force feedback glove, allowing user interaction with a virtual environment. This consists of four rehabilitation routines, each designed to exercise one specific parameter of hand movement: range, speed, fractionation or strength. The use of performance-based target levels is designed to increase patient motivation and individualize exercise difficulty to a patient's current state. Pilot clinical trials have been performed using the above system combined with noncomputer tasks, such as pegboard insertion or tracing of two-dimensional (2-D) patterns. Three chronic stroke patients used this rehabilitation protocol daily for two weeks. Objective measurements showed that each patient showed improvement on most of the hand parameters over the course of the training. Subjective evaluation by the patients was also positive. This technical report focuses on this newly developed technology for VR rehabilitation.

Making advances - but not too quickly and not too many

The World Congress of Neurology is one of the major international neurology conferences, and this year's meeting, held June 1722, brought almost 5,000 delegates to London from all corners of the globe. At the opening address, President of the World Federation of Neurology James Toole called on neurologists to use the greatly improved means of communication to improve society.

TDM: the key to more effective HIV treatment?

At the 5th International Congress on Drug Therapy in HIV Infection, held in Glasgow, Scotland, October 22-26, 2000, the increasingly important role of the clinical pharmacologist was underlined. Now that complicated combination therapy regimens are routine in HIV treatment, therapeutic drug monitoring (TDM) is increasingly necessary to monitor drug levels in blood, potential drug interactions, changes in bioavailability and patient nonadherence. Most of the congress was devoted to the presentation of the latest clinical data on the major drugs and their most important combinations used for HAART, including data on trials with nelfinavir, indinavir, BMS-232632, ritonavir, nevirapine, lamivudine/zidovudine and lopinavir/ritonavir, as well as with dronabinol. The sense of optimism triggered by the advent of HAART in the last few years continues to grow, and this will clearly be encouraged by more efficient approaches to treatment such as the advent of TDM.

The sartans are coming!

The 3(rd) International Symposium on Angiotensin II Antagonism was held in London February 28-March 2, 2000, and was accompanied by a number of company-sponsored symposia discussing "sartan" drugs. The advent of these angiotensin II receptor antagonists in the 1990s was welcomed with much enthusiasm owing to their reduced side effect profiles in comparison with members of other classes of antihypertensive drugs. Losartan and valsartan had previously been combined successfully with hydrochlorothiazide. A new sartan combination--candesartan cilexetil + hydrochlorothiazide--was announced during the meeting and new clinical trial data were presented. There are a number of questions that still need answers with respect to the role of the sartans in areas other than hypertension; help in answering at least some of these questions should be provided soon by the results of several megastudies that are currently under way.

A novel quantitative method for 3D measurement of Parkinsonian tremor

OBJECTIVE

To demonstrate the usefulness of a three dimensional (3D) motion analysis system for the quantitative measurement of tremor in patients with Parkinson's disease (PD).

METHODS

Six PD patients with hand tremors were studied using a system that employed 3D electromagnetic position sensors to measure the actual, cumulative displacement of the tremoring finger. Patients were studied in different hand positions and activating conditions before and 30, 60, 90 and 120 min after intake of Pramipexole, a dopamine agonist known to reduce tremor. Tremor amplitude and frequency, before and after drug intake, were compared using Mann-Whitney U test and Wilcoxon rank test, respectively.

RESULTS

The motion analysis system allowed discrimination of tremor related events from movement artifact and allowed the calculation of real world movement of the finger tremor despite altered hand positions and orientation. Average 3D tremor frequency ranged from 3.71 to 4.34 Hz. Median tremor amplitude (total distance traveled per 5 s interval) decreased with drug from 4.9 to 1.6 cm for resting tremor, 4.5 to 3.7 cm for postural tremor, 3.4 to 3.3 cm for precision tremor, 10.2 to 3.3 cm for tapping activation and 108.6 to 5.7 cm for counting activation.

CONCLUSIONS

Our method of 3D analysis provides a robust, single quantitative measure of tremor amplitude that is intuitive and likely to reflect the functional impact of tremor. This methodology should be useful in comparing tremor across patients and in measuring the efficacy of therapeutic interventions.

Immunodeficiency and the gut: clues to the role of the immune system in gastrointestinal disease

Gastrointestinal disease occurs in a high proportion of patients with primary immunodeficiency. While enteric infections are responsible for the gastrointestinal pathology in many individuals, it is now clear that infection alone is not sufficient to explain the gut pathology found in many immunodeficiencies. This article focuses on recent developments in this field and highlights the insights gained in understanding the complex relationship between immunodeficiency and the gut.

Simultaneous genotyping for all three known structural mutations in the human mannose-binding lectin gene

We describe a rapid and simple method for genotyping the three known structural mutations within exon 1 of the mannan-binding lectin (MBL) gene. A PCR-amplifiable synthetic DNA (Universal Heteroduplex Generator) was annealed to genomic PCR product from exon 1 to generate unique DNA heteroduplexes for each mutation. Heteroduplexes were then resolved by non-denaturing polyacrylamide gel electrophoresis. The technique was initially validated with previously typed samples and then applied to previously untyped samples with the results confirmed by DNA sequencing.

Haptoglobin typing of bloodstains using horizontal discontinuous polyacrylamide gel electrophoresis

A horizontal electrophoresis method using a discontinuous polyacrylamide gel to identify haptoglobin polymorphs is described. Improvements over the traditional vertical gel method include less sample required, easy gel preparation, and shortened run time. Additionally, vertical electrophoresis equipment, which can be technically challenging, is not needed. Caucasian, Black and Hispanic databases, each created from 100 autopsy blood samples from the New York City Medical Examiner's Office, are also presented.