11 research outputs found

    USPIO-enhanced MRI for preoperative staging of gynecological pelvic tumors: preliminary results

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    The aim of this study was to assess nodal enhancement with ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI) during preoperative staging of gynecological pelvic tumors within the same imaging session for the primary tumor. Pelvic MRI was performed 18-28h after intravenous infusion of USPIO (Combidex/Sinerem, 2.6mg Fe/kg body weight) in 13 women (mean age 51 years) scheduled for surgery for biopsy proven (n=11) or clinically suspected (n=2) uterine carcinoma. Axial T1-weighted spin-echo (SE), T2-weighted fast SE (FSE; with fat saturation), fast spoiled gradient-recalled (FSPGR) echo, sagittal and oblique T2-weighted FSE sequences were acquired on a 1.5-T system. Lymph nodes were prospectively staged using standard criteria, i.e., size and shape, as well as USPIO enhancement. Results were correlated with histology findings. MRI correctly staged all primary uterine tumors. In one case, the preoperative diagnosis of stage IV switched the therapeutic approach to radiochemotherapy. Ninety-one (86 benign, 5 malignant) of the histologically characterized nodes could be correlated with their MRI counterparts. One node was false positive; three micrometastases greater than 5mm and one 5-mm metastasis were missed. On a nodal basis, the sensitivity score was 0.33 and the specificity score, 0.99. On a patient basis, the sensitivity score was 0.25 and the specificity score, 0.80. Our preliminary results indicate that USPIO-enhanced pelvic MRI for preoperative nodal assessment is feasible within one imaging session for primary tumors and that it has a high specificity. However, the low sensitivity in the present study is a limitation for the clinical application of this techniqu

    The Influence of Cataract on Fluorescence Lifetime Imaging Ophthalmoscopy (FLIO).

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    Purpose To investigate the influence of lens opacifications on fluorescence lifetime imaging ophthalmoscopy (FLIO). Methods Forty-seven eyes of 45 patients were included. Mean fluorescence lifetimes (Tm) were recorded with a fluorescence lifetime imaging ophthalmoscope in a short spectral channel (SSC) and a long spectral channel (LSC). Retinal and lens autofluorescence lifetimes were measured in subjects before and after cataract surgery. Lens opacification was graded using the Lens Opacities Classification System III (LOCS III) classification. Results The retinal Tm decreased significantly after cataract surgery in both spectral channels (SSC: -53%, P < 0.0001; LSC: -26%, P = 0.0041). The lens Tm differed significantly between the crystalline and the artificial lens in both spectral channels (P < 0.0001). The "nuclear opacity" and "nuclear color" score of the LOCS III classification correlated significantly with the mean Tm difference in both spectral channels (P < 0.0001). Conclusions Lens opacification results in significantly longer retinal Tm. Therefore the lens status has to be considered when performing cross-sectional fluorescence lifetime analysis. Cataract-formation and cataract-surgery needs to be considered when conducting longitudinal studies. Grading of nuclear opacity following the LOCS III classification provides an approximate conversion formula for the mean change of lifetimes, which can be helpful in the interpretation of data in patients with lens opacities. Translational Relevance FLIO is significantly influenced by lens opacities. Using a lens opacity grading scheme and measuring fluorescence lifetimes before and after cataract surgery, an approximative conversion formula can be calculated, which enables the comparison of lifetimes after cataract surgery or over the course of time

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Fluorescence Lifetimes of Drusen in Age-Related Macular Degeneration.

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    Purpose The purpose of this study was to characterize fundus autofluorescence lifetimes of retinal drusen in patients with AMD. Methods Patients with AMD and retinal drusen and healthy controls of similar age were examined. A fluorescence lifetime imaging ophthalmoscope was used. Retinal autofluorescence was excited using a 473-nm pulsed laser, and fundus autofluorescence lifetimes of the central retina (30°) were measured in two distinct spectral channels (short: 498 to 560 nm [SSC]; long: 560 to 720 nm [LSC]). Mean retinal autofluorescence lifetimes, corresponding fundus autofluorescence intensity images, spectral domain optical coherence tomography, color fundus images, and clinical data were investigated. Patients were analyzed in two distinct groups (soft drusen and reticular pseudodrusen) and compared with control subjects. Results Sixty-four eyes of 64 patients with AMD and retinal drusen (age: mean ± SD, 78 ± 8.5 years; range, 59 to 94 years) were investigated and compared with a control group of 20 age-matched healthy subjects. Mean retinal autofluorescence lifetimes in patients with AMD was significantly prolonged compared with the healthy control eyes (mean ± SEM: SSC, 486 ± 18 vs. 332 ± 11 ps, P < 0.0001; LSC: 493 ± 9 vs. 382 ± 17 ps, P < 0.0001). Areas of drusen featured a wide range of fluorescence lifetime values. Long lifetimes were identified in areas of atrophy and in areas of intraretinal hyperreflective deposits. Short lifetimes corresponded to deposits within the photoreceptor outer segment band. Conclusions Mean retinal autofluorescence lifetimes in AMD patients are significantly prolonged. Intraretinal deposits cause prolonged lifetimes, whereas deposits in the area of the outer photoreceptor segments lead to short fluorescence lifetimes

    Fallfilmverdampfer und Verfahren zu dessen Betrieb und Verwendung

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    Die Erfindung betrifft einen Fallfilmverdampfer (1) mit zumindest einer Berieselungseinrichtung (11), zumindest einer darunter angeordneten Verdampferstruktur (12) und zumindest einem Sumpf (13), wobei die Verdampferstruktur (12) zumindest eine Heizfläche (121) aufweist, welche mit einer porösen Beschichtung (2) versehen ist, wobei die poröse Beschichtung (2) zumindest teilweise so ausgestaltet ist, dass ein mittlerer Porendurchmesser r der Poren (25) der ersten porösen Beschichtung (2) und deren größte zusammenhängende senkrechte Ausdehnung h in folgendem Zusammenhang stehen:wobei σ die Oberflächenspannung und θ den Kontaktwinkel bezeichnen, ρ die Dichte der Flüssigkeit angibt, g die Schwerebeschleunigung darstellt und F den Umlenkfaktor bezeichnet, welcher zwischen etwa 0,1 und etwa 1 oder zwischen etwa 0,2 und etwa 1 gewählt ist. Weiterhin betrifft die Erfindung ein Verfahren zur Verdampfung einer Flüssigkeit und eine Verwendung des Fallfilmverdampfers

    USPIO-enhanced MRI for preoperative staging of gynecological pelvic tumors: preliminary results

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    The aim of this study was to assess nodal enhancement with ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI) during preoperative staging of gynecological pelvic tumors within the same imaging session for the primary tumor. Pelvic MRI was performed 18-28 h after intravenous infusion of USPIO (Combidex/Sinerem, 2.6 mg Fe/kg body weight) in 13 women (mean age 51 years) scheduled for surgery for biopsy proven ( n=11) or clinically suspected ( n=2) uterine carcinoma. Axial T1-weighted spin-echo (SE), T2-weighted fast SE (FSE; with fat saturation), fast spoiled gradient-recalled (FSPGR) echo, sagittal and oblique T2-weighted FSE sequences were acquired on a 1.5-T system. Lymph nodes were prospectively staged using standard criteria, i.e., size and shape, as well as USPIO enhancement. Results were correlated with histology findings. MRI correctly staged all primary uterine tumors. In one case, the preoperative diagnosis of stage IV switched the therapeutic approach to radiochemotherapy. Ninety-one (86 benign, 5 malignant) of the histologically characterized nodes could be correlated with their MRI counterparts. One node was false positive; three micrometastases greater than 5 mm and one 5-mm metastasis were missed. On a nodal basis, the sensitivity score was 0.33 and the specificity score, 0.99. On a patient basis, the sensitivity score was 0.25 and the specificity score, 0.80. Our preliminary results indicate that USPIO-enhanced pelvic MRI for preoperative nodal assessment is feasible within one imaging session for primary tumors and that it has a high specificity. However, the low sensitivity in the present study is a limitation for the clinical application of this technique

    Preoperative breast cancer staging: MR imaging of the axilla with ultrasmall superparamagnetic iron oxide enhancement

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    PURPOSE To evaluate magnetic resonance (MR) imaging with ultrasmall superparamagnetic iron oxide (USPIO) enhancement for preoperative axillary lymph node staging in patients with breast cancer by using histopathologic findings as the standard of reference. MATERIALS AND METHODS MR imaging was performed with a 1.5-T system within 24-36 hours after the start of intravenous slow-drip infusion of USPIO in 20 patients with breast cancer who were scheduled for surgery, followed by gadolinium-enhanced MR imaging. Lymph nodes were staged prospectively by using newly established criteria, and results were correlated with histologic findings. RESULTS In two patients, preoperative findings led to a change in therapeutic approach, and neoadjuvant chemotherapy was given; both patients were excluded from statistical analysis. Results of axillary staging with USPIO-enhanced MR imaging were true-positive in nine, true-negative in seven, false-positive in zero, and false-negative in two of 18 patients (sensitivity, 82%; specificity, 100%; positive predictive value, 100%; second reader, kappa = 1.0). Four hundred five lymph nodes were detected with MR imaging. For first and second readers, respectively, lymph node-based sensitivity was 83% and 73% and specificity was 96% and 97% (kappa = 0.68). USPIO as the intravascular contrast agent could not replace gadolinium for assessment of the primary tumor; however, no clinically relevant interaction was seen. Thus, an integrated imaging approach was feasible in all patients. CONCLUSION USPIO-enhanced MR imaging has the potential to become an adjunct to conventional MR imaging of the breast for preoperative assessment of axillary lymph nodes in patients with breast cancer
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