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41.
Lukas Reznicek Sarah Cserhati Florian Seidensticker Raffael Liegl Anselm Kampik Michael Ulbig Aljoscha S. Neubauer Marcus Kernt 《Acta ophthalmologica. Supplement》2013,91(7):e529-e536
Purpose: To evaluate macular morphology and function in diabetic macular edema (DME) over the course of intravitreal anti‐vascular endothelial growth factor (VEGF) treatment with Ranibizumab. Methods: A consecutive series of 39 study eyes with centre‐involving DME were included in this study. In all subjects, best‐corrected visual acuity (BCVA) according ETDRS protocol, fluorescein angiography (FA), microperimetric macular sensitivity (MP) and Spectral Domain optical coherence tomography (SD‐OCT) cross‐sectional scans were obtained before treatment and after 3 monthly applied intravitreal Ranibizumab injections. Six different morphological qualities [IS/OS layer integrity, outer nuclear layer (ONL) cysts, ONL cyst size, inner nuclear layer (INL) cysts, blocking phenomenon and subretinal fluid] were graded of each cross‐sectional OCT scan before and over the course of treatment by two experienced graders. Correlation analyses between functional and morphological parameters were obtained. Results: Mean BCVA increased from 26 ± 14 to 33 ± 13 letters after 3 consecutive monthly applied Ranibizumab injections (p < 0.001). Central retinal thickness (CRT) decreased from 504 ± 144 to 387 ± 122 μm (p < 0.001). Over the course of treatment, IS/OS continuity improved (index: 0.56 ± 0.52 to 0.43 ± 0.49, Z = ?1.415, p = 0.157), ONL cyst prevalence and size decreased significantly (index: 0.61 ± 0.44 to 0.56 ± 0.35, Z = ?3.41, p = 0.001 and 1.75 ± 0.88 to 1.17 ± 1.05, Z = ?4.02, p < 0.001), INL cyst prevalence decreased (index: 0.35 ± 0.52 to 0.28 ± 0.52, Z = ?1.60, p = 0.109), blocking phenomenon did not change significantly (index: 00.12 ± 0.16 to 0.13 ± 0.15, Z = ?0.45, p = 0.656) and subretinal fluid almost disappeared (index: 0.10 ± 0.24 vs. 0.00 ± 0.01, Z = ?2.56, p = 0.011). Correlation analyses revealed highest significant correlations between ONL cyst prevalence and their size and CRT as well as BCVA and MP before treatment and over the course of treatment. Conclusions: ONL cysts and their size as morphological parameters correlate with retinal function measured with BCVA and microperimetry before and over the course of anti‐VEGF therapy with Ranibizumab in patients with DME. 相似文献
42.
A 2,5-disubstituted tetrazole with p-nitrophenyl and 3-pyridyl units as acceptors (1a), and three push–pull tetrazoles with p-nitrophenyl as an acceptor and phenyl (1b), 2-(dibenzo[b,d]furan-4-yl) (1c), and 4-(N,N-diphenylamino)phenyl (1d) as donor groups, were synthesized by copper-catalyzed aerobic C–N coupling of p-nitrophenyl tetrazole with appropriately substituted aryl boronic acids. The absorption and emission spectra of 1a–c showed minimal dependence on the polarity of the solvent; however, in the case of 1d a blue shift was noted in the longest absorption band (λ1) as the polarity increased. The fluorescence intensity of the title compounds was found to be solvent-dependent; however, no apparent correlation to solvent polarity could be established. The absorption and emission characteristics of 1a–d were also influenced by the nature of the substituent as 1d, bearing a strong electron donating 4-(N,N-diphenylamino)phenyl group, displayed a significant red shifted absorption (λ1) as well as emission (λem) bands compared to other compounds. Time dependent density functional calculations (CAM-B3LYP/6-311++G**) revealed that the longest wavelength band (λ1) is associated with an intramolecular charge transfer (ICT) from HOMO/HOMO-1/HOMO-2 → LUMO/LUMO+1 in these molecules. The first hyperpolarizability values, βHRS, of 1a–d were measured using the solution-based hyper-Rayleigh scattering technique using a femtosecond Ti:Sapphire laser and the highest NLO activity was measured for 1d with the greatest push–pull characteristics. A strong correlation was observed between the calculated hyperpolarizability (βtot) and experimentally measured values (βHRS).A 2,5-disubstituted tetrazole with a p-nitrophenyl unit as an acceptor and a 4-(N,N-diphenylamino) phenyl group as a donor exhibits strong push–pull characteristics and displays high NLO activity. 相似文献
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Shih-Te Hung Jelmer Cnossen Daniel Fan Marijn Siemons Daphne Jurriens Kristin Grußmayer Oleg Soloviev Lukas C. Kapitein Carlas S. Smith 《Biomedical optics express》2022,13(6):3275
High-NA light sheet illumination can improve the resolution of single-molecule localization microscopy (SMLM) by reducing the background fluorescence. These approaches currently require custom-made sample holders or additional specialized objectives, which makes the sample mounting or the optical system complex and therefore reduces the usability of these approaches. Here, we developed a single-objective lens-inclined light sheet microscope (SOLEIL) that is capable of 2D and 3D SMLM in thick samples. SOLEIL combines oblique illumination with point spread function PSF engineering to enable dSTORM imaging in a wide variety of samples. SOLEIL is compatible with standard sample holders and off-the-shelve optics and standard high NA objectives. To accomplish optimal optical sectioning we show that there is an ideal oblique angle and sheet thickness. Furthermore, to show what optical sectioning delivers for SMLM we benchmark SOLEIL against widefield and HILO microscopy with several biological samples. SOLEIL delivers in 15 μm thick Caco2-BBE cells a 374% higher intensity to background ratio and a 54% improvement in the estimated CRLB compared to widefield illumination, and a 184% higher intensity to background ratio and a 20% improvement in the estimated CRLB compared to HILO illumination. 相似文献
45.
Richard S P Huang Julie Y Tse Lukas Harries Ryon P Graf Douglas I Lin Karthikeyan Murugesan Matthew C Hiemenz Vamsi Parimi Tyler Janovitz Brennan Decker Eric Severson Mia A Levy Shakti H Ramkissoon Julia A Elvin Jeffrey S Ross Erik A Williams 《The oncologist》2022,27(8):655
BackgroundIn the current study, we examined the real-world prevalence of highly pigmented advanced melanomas (HPMel) and the clinicopathologic, genomic, and ICPI biomarker signatures of this class of tumors.Materials and MethodsOur case archive of clinical melanoma samples for which the ordering physician requested testing for both PD-L1 immunohistochemistry (IHC) and comprehensive genomic profiling (CGP) was screened for HPMel cases, as well as for non-pigmented or lightly pigmented advanced melanoma cases (LPMel).ResultsOf the 1268 consecutive melanoma biopsies in our archive that had been submitted for PD-L1 IHC, 13.0% (165/1268) were HPMel and 87.0% (1103/1268) were LPMel. In the HPMel cohort, we saw a significantly lower tumor mutational burden (TMB, median 8.8 mutations/Mb) than in the LPMel group (11.4 mut/Mb), although there was substantial overlap. In examining characteristic secondary genomic alterations (GA), we found that the frequencies of GA in TERTp, CDKN2A, TP53, and PTEN were significantly lower in the HPMel cases than in LPMel. A higher rate of GA in CTNNB1, APC, PRKAR1A, and KIT was identified in the HPMel cohort compared with LPMel.ConclusionsIn this study, we quantified the failure rates of melanoma samples for PD-L1 testing due to high melanin pigmentation and showed that CGP can be used in these patients to identify biomarkers that can guide treatment decisions for HPMel patients. Using this practical clinical definition for tumor pigmentation, our results indicate that HPMel are frequent at 13% of melanoma samples, and in general appear molecularly less developed, with a lower TMB and less frequent secondary GA of melanoma progression. 相似文献
46.
Wilhelm Wimmer Moritz von Werdt Georgios Mantokoudis Lukas Anschuetz Martin Kompis Marco Caversaccio 《Auris, nasus, larynx》2019,46(5):681-686
ObjectiveTo re-evaluate current indication criteria and to estimate the audiological outcomes of patients with Bonebridge bone conduction implants based on preoperative bone conduction thresholds.MethodsWe assessed the outcome of 28 subjects with either conductive or mixed hearing loss (CMHL) or single-sided deafness (SSD) who were undergoing a Bonebridge implantation. We used linear regression to evaluate the influence of preoperative bone conduction thresholds of the better/poorer ear, indication group, and language (German- and French-speaking patients) on aided sound field thresholds. In addition, aided word recognition scores at 65 dB sound pressure level were fit with a logistic model that included preoperative bone conduction thresholds of the better/poorer ear, indication group, and language as effects.ResultsWe found that both aided sound field thresholds and word recognition were correlated with the preoperative bone conduction thresholds of the better hearing ear. No correlation between audiological outcomes and the preoperative bone conduction thresholds of the poorer ear, language, or indication group was found.ConclusionBone conduction thresholds of the better hearing ear should be used to estimate the outcome of patients undergoing Bonebridge implantation. We suggest the indication criteria for Bonebridge candidates considering maximal bone conduction thresholds of the better ear at 38 dB HL to achieve an aided sound field threshold of at least 30 dB hearing level and an aided word recognition score of at least 75% for monosyllabic words. 相似文献
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