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The article discusses research on the development of a novel experimental device used in the elevated-electrospinning of highly volatile and rapidly crystallizing polymer solutions and melts. Researchers studied the main parameters of the gentle annular gas veil in this electrospinning process. Also determined were the ways in which electrical conductivity of solvents influenced the diameter of electrospun fibers composed of ultra-high molecular weight polyethylene. Factors that aided the formation of a suitable fiber structure included polymer solution concentration, conductivity, and temperature.

Aim: In this study we present and evaluated a new registration technology for the jaw-bone surface. It is based on a micromechatronic device for the generation of a 'mechanical image' of the bone surface by means of an array of micro-needles that are penetrating the soft tissue until they touch the surface of the bone. This 'mechanical impression image' is aligned with the CT data set. Material and Methods: Based on laboratory measurements on 10 specially prepared jawbone models we evaluate the accuracy of this new registration method. Results: Our measurements of the 10 specimens revealed a maximum overall location error of 0.97 mm (range: 0.35-0.97 mm). Conclusions: From the technical point of view the presented registration technology has the potential to improve the performance (i.e. accuracy and avoidance of errors) of the registration process for bony structures in selected applications of image-guided surgery. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The ability of readily available clinical information to predict the occurrence of diabetic foot ulcer has not been extensively studied. We conducted a prospective study of the individual and combined effects of commonly available clinical information in the prediction of diabetic foot ulcer occurrence. RESEARCH DESIGN AND METHODS: We followed 1,285 diabetic veterans without foot ulcer for this outcome with annual clinical evaluations and quarterly mailed questionnaires to identify foot problems. At baseline we assessed age; race; weight; current smoking; diabetes duration and treatment; HbA(1c) (A1C); visual acuity; history of laser photocoagulation treatment, foot ulcer, and amputation; foot shape; claudication; foot insensitivity to the 10-g monofilament; foot callus; pedal edema; hallux limitus; tinea pedis; and onychomycosis. Cox proportional hazards modeling was used with backwards stepwise elimination to develop a prediction model for the first foot ulcer occurrence after the baseline examination. RESULTS: At baseline, subjects were 62.4 years of age on average and 98% male. Mean follow-up duration was 3.38 years, during which time 216 foot ulcers occurred, for an incidence of 5.0/100 person-years. Significant predictors (P < or = 0.05) of foot ulcer in the final model (hazard ratio, 95% CI) included A1C (1.10, 1.06-1.15), impaired vision (1.48, 1.00-2.18), prior foot ulcer (2.18, 1.61-2.95), prior amputation (2.57, 1.60-4.12), monofilament insensitivity (2.03, 1.50-2.76), tinea pedis (0.73, 0.54-0.98), and onychomycosis (1.58, 1.16-2.16). Area under the receiver operating characteristic curve was 0.81 at 1 year and 0.76 at 5 years. CONCLUSIONS: Readily available clinical information has substantial predictive power for the development of diabetic foot ulcer and may help in accurately targeting persons at high risk of this outcome for preventive interventions. [ABSTRACT FROM AUTHOR]

BACKGROUND: Biomarkers may play an important role in identifying patients at risk for cancer therapy cardiotoxicity. Our objectives were to define the patterns of change in biomarkers with cancer therapy and their associations with cardiotoxicity. METHODS: In a multicenter cohort of 78 breast cancer patients undergoing doxorubicin and trastuzumab therapy, 8 biomarkers were evaluated at baseline and every 3 months over a maximum follow-up of 15 months. These biomarkers, hypothesized to be mechanistically relevant to cardiotoxicity, included high-sensitivity cardiac troponin I (hs-cTnI), high-sensitivity C-reactive protein (hsCRP), N-terminal pro–B-type natriuretic peptide (NT-proBNP), growth differentiation factor 15 (GDF-15), myeloperoxidase (MPO), placental growth factor (PlGF), soluble fms-like tyrosine kinase receptor-1 (sFlt-1), and galectin 3 (gal-3). We determined if biomarker increases were associated with cardiotoxicity at the same visit and the subsequent visit over the entire course of therapy. Cardiotoxicity was defined by the Cardiac Review and Evaluation Criteria; alternative definitions were also considered. RESULTS: Across the entire cohort, all biomarkers except NT-proBNP and gal-3 demonstrated increases by 3 months; these increases persisted for GDF-15, PlGF, and hs-cTnI at 15 months. Increases in MPO, PlGF, and GDF-15 were associated with cardiotoxicity at the same visit [MPO hazard ratio 1.38 (95% CI 1.10–1.71), P = 0.02; PlGF 3.78 (1.30–11.0), P = 0.047; GDF-15 1.71 (1.15–2.55), P = 0.01] and the subsequent visit. MPO was robust to alternative outcome definitions. CONCLUSIONS: Increases in MPO are associated with cardiotoxicity over the entire course of doxorubicin and trastuzumab therapy. Assessment with PlGF and GDF-15 may also be of value. These findings motivate validation studies in additional cohorts.

Alzheimer’s disease (AD) involves selective loss of muscarinic m2, but not m1, subtype neuroreceptors in cortical and hippocampal regions of the human brain. Until recently, emission tomographic study of the loss of m2 receptors in AD has been limited by the absence of available m2-selective radioligands that can penetrate the blood-brain barrier. We now demonstrate the in vivo m2 selectivity of an analog of (R)-QNB, 3-quinuclidinyl 2-(5-bromothienyl)-2-thienylglycolate (BrQNT), by dissection and autoradiographic studies of the in vivo inhibition of radioiodinated Z-1-azabicyclo[2.2.2]oct-3-yl α-hydroxy-α-(1-iodo-1-propen-3-yl)-α-phenylacetate (Z-(-,-)-[125I]IQNP) binding by unlabeled BrQNT in rat brain. In the absence of BrQNT, Z-(-,-)-[125I]IQNP labels brain regions containing muscarinic receptors, with an enhanced selectivity for the m2 subtype. In the presence of 60–180 nmol of co-injected racemic BrQNT, Z-(-,-)-[125I]IQNP labeling in those brain regions containing predominantly m2 subtype is reduced to background levels, while levels of radioactivity in areas not enriched in the m2 subtype do not significantly decrease. We conclude that BrQNT is m2-selective in vivo, and that [76Br]BrQNT, or a radiofluorinated analog, may be of potential use in positron emission tomographic (PET) study of the loss of m2 receptors in AD. In addition, a radioiodinated analog may be of potential use in single photon emission tomographic (SPECT) studies. [ABSTRACT FROM AUTHOR]

Background: Because cancer patients survive longer, the impact of cardiotoxicity associated with the use of cancer treatments escalates. The present study investigates whether early alterations of myocardial strain and blood biomarkers predict incident cardiotoxicity in patients with breast cancer during treatment with anthracyclines, taxanes, and trastuzumab. Methods and Results: Eighty-one women with newly diagnosed human epidermal growth factor receptor 2–positive breast cancer, treated with anthracyclines followed by taxanes and trastuzumab were enrolled to be evaluated every 3 months during their cancer therapy (total of 15 months) using echocardiograms and blood samples. Left ventricular ejection fraction, peak systolic longitudinal, radial, and circumferential myocardial strain were calculated. Ultrasensitive troponin I, N-terminal pro–B-type natriuretic peptide, and the interleukin family member (ST2) were also measured. Left ventricular ejection fraction decreased (64 ± 5% to 59 ± 6%; P<0.0001) over 15 months. Twenty-six patients (32%, [22%–43%]) developed cardiotoxicity as defined by the Cardiac Review and Evaluation Committee Reviewing Trastuzumab; of these patients, 5 (6%, [2%–14%]) had symptoms of heart failure. Peak systolic longitudinal myocardial strain and ultrasensitive troponin I measured at the completion of anthracyclines treatment predicted the subsequent development of cardiotoxicity; no significant associations were observed for left ventricular ejection fraction, N-terminal pro–B-type natriuretic peptide, and ST2. Longitudinal strain was <19% in all patients who later developed heart failure. Conclusions: In patients with breast cancer treated with anthracyclines, taxanes, and trastuzumab, systolic longitudinal myocardial strain and ultrasensitive troponin I measured at the completion of anthracyclines therapy are useful in the prediction of subsequent cardiotoxicity and may help guide treatment to avoid cardiac side-effects.