The Progression of the Stargardt Disease Type 4 (ProgStar-4) Study: Design and Baseline Characteristics (ProgStar-4 Report No. 1)

BACKGROUND/AIMS: To describe the design and baseline characteristics of patients enrolled in the multicenter, prospective natural history study of Stargardt disease type 4. METHODS: Fifteen eligible patients aged 6 years and older at baseline, harboring disease-causing variants in the PROM1 gene, and with specified ocular lesions were enrolled. They were examined at baseline using a standard protocol, with 6 monthly follow-up visits for a 2-year period including best-corrected ETDRS visual acuity, spectral-domain optical coherence tomography, fundus autofluorescence (FAF), mesopic and scotopic microperimetry (MP). Areas of definitely decreased FAF (DDAF) and questionably decreased FAF were outlined and quantified on FAF images. RESULTS: Amongst the 15 patients (29 eyes) that were enrolled at 5 centers in the USA and Europe, 10 eyes (34.5%) had areas of DDAF with an average lesion area of 3.2 ± 3.5 mm2 (range 0.36-10.39 mm2) at baseline. The mean retinal sensitivity of the posterior pole derived from mesopic MP was 8.8 ± 5.8 dB. CONCLUSIONS: Data on disease progression in PROM1-related retinopathy from this study will contribute to the characterization of the natural history of disease and the exploration of the utility of several modalities to track progression and therefore to potentially be used in future interventional clinical trials

Inhibition of breathing after surfactant depletion is achieved at a higher arterial PCO(2 )during ventilation with liquid than with gas

BACKGROUND: Inhibition of phrenic nerve activity (PNA) can be achieved when alveolar ventilation is adequate and when stretching of lung tissue stimulates mechanoreceptors to inhibit inspiratory activity. During mechanical ventilation under different lung conditions, inhibition of PNA can provide a physiological setting at which ventilatory parameters can be compared and related to arterial blood gases and pH. OBJECTIVE: To study lung mechanics and gas exchange at inhibition of PNA during controlled gas ventilation (GV) and during partial liquid ventilation (PLV) before and after lung lavage. METHODS: Nine anaesthetised, mechanically ventilated young cats (age 3.8 ± 0.5 months, weight 2.3 ± 0.1 kg) (mean ± SD) were studied with stepwise increases in peak inspiratory pressure (PIP) until total inhibition of PNA was attained before lavage (with GV) and after lavage (GV and PLV). Tidal volume (V(t)), PIP, oesophageal pressure and arterial blood gases were measured at inhibition of PNA. One way repeated measures analysis of variance and Student Newman Keuls-tests were used for statistical analysis. RESULTS: During GV, inhibition of PNA occurred at lower PIP, transpulmonary pressure (Ptp) and Vt before than after lung lavage. After lavage, inhibition of inspiratory activity was achieved at the same PIP, Ptp and Vt during GV and PLV, but occurred at a higher PaCO(2 )during PLV. After lavage compliance at inhibition was almost the same during GV and PLV and resistance was lower during GV than during PLV. CONCLUSION: Inhibition of inspiratory activity occurs at a higher PaCO(2 )during PLV than during GV in cats with surfactant-depleted lungs. This could indicate that PLV induces better recruitment of mechanoreceptors than GV

Diagnostic and therapeutic approaches for nonmetastatic breast cancer in Canada, and their associated costs

In an era of fiscal restraint, it is important to evaluate the resources required to diagnose and treat serious illnesses. As breast cancer is the major malignancy affecting Canadian women, Statistics Canada has analysed the resources required to manage this disease in Canada, and the associated costs. Here we report the cost of initial diagnosis and treatment of nonmetastatic breast cancer, including adjuvant therapies. Treatment algorithms for Stages I, II, and III of the disease were derived by age group (< 50 or ≥ 50 years old), principally from Canadian cancer registry data, supplemented, where necessary, by the results of surveys of Canadian oncologists. Data were obtained on breast cancer incidence by age, diagnostic work-up, stage at diagnosis, initial treatment, follow-up practice, duration of hospitalization and direct care costs. The direct health care costs associated with ‘standard’ diagnostic and therapeutic approaches were calculated for a cohort of 17 700 Canadian women diagnosed in 1995. Early stage (Stages I and II) breast cancer represented 87% of all incident cases, with 77% of cases occurring in women ≥ 50 years. Variations were noted in the rate of partial vs total mastectomy, according to stage and age group. Direct costs for diagnosis and initial treatment ranged from $8014 for Stage II women ≥ 50 years old, to$10 897 for Stage III women < 50 years old. Except for Stage III women < 50 years old, the largest expenditure was for hospitalization for surgery, followed by radiotherapy costs. Chemotherapy was the largest cost component for Stage III women < 50 years old. This report describes the cost of diagnosis and initial treatment of nonmetastatic breast cancer in Canada, assuming current practice patterns. A second report will describe the lifetime costs of treating all stages of breast cancer. These data will then be incorporated into Statistics Canada's Population Health Model (POHEM) to perform cost-effectiveness studies of new therapeutic interventions for breast cancer, such as the cost-effectiveness of day surgery, or of radiotherapy to all breast cancer patients undergoing breast surgery. © 1999 Cancer Research Campaig

The oncolytic effect in vivo of reovirus on tumour cells that have survived reovirus cell killing in vitro

The use of oncolytic viruses has received considerable attention in recent years and many viruses have proved to be effective against a variety of cancer models and a few are currently being used in clinical trials. However, the possible emergence and outcome of virus-resistant tumour cells has not been addressed. We previously reported the effective use of reovirus against lymphoid malignancies, including the Burkitt's lymphoma cell line Raji. Here we isolated in vitro persistently infected (PI) Raji cells, and cells ‘cured' of persistent reovirus infection (‘cured' cells). Both PI and cured Raji cells resisted reovirus infection and cell killing in vitro. In vivo, the PI cells were non-tumorigenic in SCID mice, but cured cells regained the parental cells' ability to form tumours. Tumour xenografts from the cured cells, however, were highly susceptible to reovirus oncolysis in vivo. This susceptibility was due to the proteolytic environment within tumours that facilitates reovirus infection and cell killing. Our results show that persistent infection by reovirus impedes tumour development and that although PI cells cleared of reovirus are tumorigenic, they are killed upon rechallenge with reovirus. Both the PI and cured states are therefore not likely to be significant barriers to reovirus oncolytic therapy

Longitudinal Changes of Fixation Location and Stability Within 12 Months in Stargardt Disease: ProgStar Report No. 12

Purpose: To investigate the natural history of Stargardt disease (STGD1) using fixation location and fixation stability. // Design: Multicenter, international, prospective cohort study. // Methods: Fixation testing was performed using the Nidek MP-1 microperimeter as part of the prospective, multicenter, natural history study on the Progression of Stargardt disease (ProgStar). A total of 238 patients with ABCA4-related STGD1 were enrolled at baseline (bilateral enrollment in 86.6%) and underwent repeat testing at months 6 and 12. // Results: Outcome measures included the distance of the preferred retinal locus from the fovea (PRL) and the bivariate contour ellipse area (BCEA). After 12 months of follow-up, the change in the eccentricity of the PRL from the anatomic fovea was −0.0014 degrees (95% confidence interval [CI], −0.27 degrees, 0.27 degrees; P = .99). The deterioration in the stability of fixation as expressed by a larger BCEA encompassing 1 standard deviation of all fixation points was 1.21 degrees squared (deg2) (95% CI, −1.23 deg2, 3.65 deg2; P = .33). Eyes with increases and decreases in PRL eccentricity and/or BCEA values were observed. // Conclusions: Our observations point to the complexity of fixation parameters. The association of increasingly eccentric and unstable fixation with longer disease duration that is typically found in cross-sectional studies may be countered within individual patients by poorly understood processes like neuronal adaptation. Nevertheless, fixation parameters may serve as useful secondary outcome parameters in selected cases and for counseling patients to explain changes to their visual functionality

Knowledge translation on dementia: a cluster randomized trial to compare a blended learning approach with a "classical" advanced training in GP quality circles

<p>Abstract</p> <p>Background</p> <p>Thus far important findings regarding the dementia syndrome have been implemented into patients' medical care only inadequately. A professional training accounting for both, general practitioners' (GP) needs and learning preferences as well as care-relevant aspects could be a major step towards improving medical care. In the WIDA-study, entitled "Knowledge translation on dementia in general practice" two different training concepts are developed, implemented and evaluated. Both concepts are building on an evidence-based, GP-related dementia guideline and communicate the guideline's essential insights.</p> <p>Methods/Design</p> <p>Both development and implementation emphasize a procedure that is well-accepted in practice and, thus, can achieve a high degree of external validity. This is particularly guaranteed through the preparation of training material and the fact that general practitioners' quality circles (QC) are addressed. The evaluation of the two training concepts is carried out by comparing two groups of GPs to which several quality circles have been randomly assigned. The primary outcome is the GPs' knowledge gain. Secondary outcomes are designed to indicate the training's potential effects on the GPs' practical actions. In the first training concept (study arm A) GPs participate in a structured case discussion prepared for by internet-based learning material ("blended-learning" approach). The second training concept (study arm B) relies on frontal medical training in the form of a slide presentation and follow-up discussion ("classical" approach).</p> <p>Discussion</p> <p>This paper presents the outline of a cluster-randomized trial which has been peer reviewed and support by a national funding organization – Federal Ministry of Education and Research (BMBF) – and is approved by an ethics commission. The data collection has started in August 2006 and the results will be published independently of the study's outcome.</p> <p>Trial Registration</p> <p>Current Controlled Trials [ISRCTN36550981]</p

The Lysosome and Intracellular Signalling.

In addition to being the terminal degradative compartment of the cell's endocytic and autophagic pathways, the lysosome is a multifunctional signalling hub integrating the cell's response to nutrient status and growth factor/hormone signalling. The cytosolic surface of the limiting membrane of the lysosome is the site of activation of the multiprotein complex mammalian target of rapamycin complex 1 (mTORC1), which phosphorylates numerous cell growth-related substrates, including transcription factor EB (TFEB). Under conditions in which mTORC1 is inhibited including starvation, TFEB becomes dephosphorylated and translocates to the nucleus where it functions as a master regulator of lysosome biogenesis. The signalling role of lysosomes is not limited to this pathway. They act as an intracellular Ca2+ store, which can release Ca2+ into the cytosol for both local effects on membrane fusion and pleiotropic effects within the cell. The relationship and crosstalk between the lysosomal and endoplasmic reticulum (ER) Ca2+ stores play a role in shaping intracellular Ca2+ signalling. Lysosomes also perform other signalling functions, which are discussed. Current views of the lysosomal compartment recognize its dynamic nature. It includes endolysosomes, autolysosome and storage lysosomes that are constantly engaged in fusion/fission events and lysosome regeneration. How signalling is affected by individual lysosomal organelles being at different stages of these processes and/or at different sites within the cell is poorly understood, but is discussed