@article{RischStollSchomoelleretal.2020, author = {Risch, Lucie and Stoll, Josefine and Schom{\"o}ller, Anne and Engel, Tilman and Mayer, Frank and Cassel, Michael}, title = {Intraindividual Doppler Flow Response to Exercise Differs Between Symptomatic and Asymptomatic Achilles Tendons}, series = {Frontiers in physiology}, volume = {12}, journal = {Frontiers in physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne, Schweiz}, issn = {1664-042X}, doi = {10.3389/fphys.2021.617497}, pages = {1 -- 8}, year = {2020}, abstract = {Objective: This study investigated intraindividual differences of intratendinous blood flow (IBF) in response to running exercise in participants with Achilles tendinopathy. Design: This is a cross-sectional study. Setting: The study was conducted at the University Outpatient Clinic. Participants: Sonographic detectable intratendinous blood flow was examined in symptomatic and contralateral asymptomatic Achilles tendons of 19 participants (42 ± 13 years, 178 ± 10 cm, 76 ± 12 kg, VISA-A 75 ± 16) with clinically diagnosed unilateral Achilles tendinopathy and sonographic evident tendinosis. Intervention: IBF was assessed using Doppler ultrasound "Advanced Dynamic Flow" before (Upre) and 5, 30, 60, and 120 min (U5-U120) after a standardized submaximal constant load run. Main Outcome Measure: IBF was quantified by counting the number (n) of vessels in each tendon. Results: At Upre, IBF was higher in symptomatic compared with asymptomatic tendons [mean 6.3 (95\% CI: 2.8-9.9) and 1.7 (0.4-2.9), p < 0.01]. Overall, 63\% of symptomatic and 47\% of asymptomatic Achilles tendons responded to exercise, whereas 16 and 11\% showed persisting IBF and 21 and 42\% remained avascular throughout the investigation. At U5, IBF increased in both symptomatic and asymptomatic tendons [difference to baseline: 2.4 (0.3-4.5) and 0.9 (0.5-1.4), p = 0.05]. At U30 to U120, IBF was still increased in symptomatic but not in asymptomatic tendons [mean difference to baseline: 1.9 (0.8-2.9) and 0.1 (-0.9 to 1.2), p < 0.01]. Conclusion: Irrespective of pathology, 47-63\% of Achilles tendons responded to exercise with an immediate acute physiological IBF increase by an average of one to two vessels ("responders"). A higher amount of baseline IBF (approximately five vessels) and a prolonged exercise-induced IBF response found in symptomatic ATs indicate a pain-associated altered intratendinous "neovascularization."}, language = {en} } @article{RischWochatzMesserschmidtetal.2017, author = {Risch, Lucie and Wochatz, Monique and Messerschmidt, Janin and Engel, Tilman and Mayer, Frank and Cassel, Michael}, title = {Reliability of evaluating achilles tendon vascularization assessed with doppler ultrasound advanced dynamic flow}, series = {Journal of ultrasound in medicine}, volume = {37}, journal = {Journal of ultrasound in medicine}, number = {3}, publisher = {Wiley}, address = {Hoboken}, issn = {0278-4297}, doi = {10.1002/jum.14414}, pages = {737 -- 744}, year = {2017}, abstract = {The reliability of quantifying intratendinous vascularization by high-sensitivity Doppler ultrasound advanced dynamic flow has not been examined yet. Therefore, this study aimed to investigate the intraobserver and interobserver reliability of evaluating Achilles tendon vascularization by advanced dynamic flow using established scoring systems. Methods-Three investigators evaluated vascularization in 67 recordings in a test-retest design, applying the Ohberg score, a modified Ohberg score, and a counting score. Intraobserver and interobserver agreement for the Ohberg score and modified Ohberg score was analyzed by the Cohen kappa and Fleiss kappa coefficients (absolute), Kendall tau b coefficient, and Kendall coefficient of concordance (W; relative). The reliability of the counting score was analyzed by intraclass correlation coefficients (ICC) 2.1 and 3.1, the standard error of measurement (SEM), and Bland-Altman analysis (bias and limits of agreement [LoA]). Results-Intraobserver and interobserver agreement (absolute/relative) ranged from 0.61 to 0.87/0.87 to 0.95 and 0.11 to 0.66/0.76 to 0.89 for the Ohberg score and from 0.81 to 0.87/0.92 to 0.95 and 0.64 to 0.80/0.88 to 0.93 for the modified Ohberg score, respectively. The counting score revealed an intraobserver ICC of 0.94 to 0.97 (SEM, 1.0-1.5; bias, -1; and LoA, 3-4 vessels). The interobserver ICC for the counting score ranged from 0.91 to 0.98 (SEM, 1.0-1.9; bias, 0; and LoA, 3-5 vessels). Conclusions-The modified Ohberg score and counting score showed excellent reliability and seem convenient for research and clinical practice. The Ohberg score revealed decent intraobserver but unexpected low interobserver reliability and therefore cannot be recommended.}, language = {en} } @article{VukicevicNeffeLuetzowetal.2015, author = {Vukicevic, Radovan and Neffe, Axel T. and Luetzow, Karola and Pierce, Benjamin F. and Lendlein, Andreas}, title = {Conditional Ultrasound Sensitivity of Poly[(N-isopropylacrylamide)-co-(vinyl imidazole)] Microgels for Controlled Lipase Release}, series = {Macromolecular rapid communications}, volume = {36}, journal = {Macromolecular rapid communications}, number = {21}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1022-1336}, doi = {10.1002/marc.201500311}, pages = {1891 -- 1896}, year = {2015}, abstract = {Triggering the release of cargo from a polymer network by ultrasonication as an external, non-invasive stimulus can be an interesting concept for on-demand release. Here, it is shown that, in pH-and thermosensitive microgels, the ultrasound sensitivity of the polymer network depends on the external conditions. Crosslinked poly[(N-isopropylacrylamide)-co-(vinyl imidazole)] microgels showed a volume phase transition temperature (VPTT) of 25-50 degrees C, which increases with decreasing pH. Above the VPTT the polymer chains are collapsed, while below VPTT they are extended. Only in the case of maximum observed swelling, where the polymer chains are expanded, the microgels are mechanically fragmented through ultrasonication. In contrast, when the polymer chains are partially collapsed it is not possible to manipulate the microgels by ultrasound. Additionally, the ultrasound-induced on-demand release of wheat germ lipase from the microgels could be demonstrated successfully. The principle of conditional ultrasound sensitivity is likely to be general and can be used for selection of matrix-cargo combinations.}, language = {en} } @article{LiWangSchlemmetal.2011, author = {Li, Jian and Wang, Zi-Neng and Schlemm, Ludwig and Pfab, Thiemo and Xiao, Xiao-Min and Chen, You-Peng and Hocher, Berthold}, title = {Low birth weight and elevated head-to-abdominal circumference ratio are associated with elevated fetal glycated serum protein concentrations}, series = {Journal of hypertension}, volume = {29}, journal = {Journal of hypertension}, number = {9}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, issn = {0263-6352}, doi = {10.1097/HJH.0b013e328349a2e6}, pages = {1712 -- 1718}, year = {2011}, abstract = {Objective To analyze the association between low birth weight, head-to-abdominal circumference ratio, and insulin resistance in early life. Method and results Glycated serum proteins (GSPs) were quantified at delivery in 612 Chinese mother/child pairs serving as a surrogate of maternal and fetal glycemia. Differential ultrasound examination of the fetal's body (head circumference, biparietal diameter, pectoral diameter, abdominal circumference, and femur length) was done in average 1 week prior to delivery. Multivariable regression analysis considering gestational age at delivery, the child's sex, maternal BMI, maternal age at delivery, maternal body weight, and pregnancyinduced hypertension revealed that fetal GSP was inversely associated with birth weight (R(2) = 0.416; P < 0.001). Fetal GSP was furthermore positively associated with the head-to-abdominal circumference ratio, whereas the maternal GSP was negatively correlated with the offspring's head-to-abdominal circumference ratio (R(2) = 0.285; P = 0.010 and R(2) = 0.261; P = 0.020, respectively). The increased head-to-abdominal circumference ratio in newborns with higher fetal GSP is mainly due to a reduced abdominal circumference rather than reduced growth of the brain. Conclusion The disproportional intrauterine growth is in line with the concept of so-called brain sparing, a mechanism maintaining the intrauterine growth of the brain at the expense of trunk growth. Our data suggest that the low birth weight phenotype, linked to cardiovascular diseases like hypertension in later life, might be a phenotype of disproportional intrauterine growth retardation and early life insulin resistance.}, language = {en} } @article{CasselMuellerCarlsohnetal.2012, author = {Cassel, Michael and M{\"u}ller, Steffen and Carlsohn, Anja and Baur, Heiner and Jerusel, N. and Mayer, Frank}, title = {Intra- and interrater variability of sonographic investigations of patella and achilles tendons}, series = {Sportverletzung, Sportschaden : Grundlagen, Pr{\"a}vention, Rehabilitation}, volume = {26}, journal = {Sportverletzung, Sportschaden : Grundlagen, Pr{\"a}vention, Rehabilitation}, number = {1}, publisher = {Thieme}, address = {Stuttgart}, issn = {0932-0555}, doi = {10.1055/s-0031-1281839}, pages = {21 -- 26}, year = {2012}, abstract = {Background: Clinical examinations of tendon disorders routinely include ultrasound examinations, despite the fact that availability of data concerning validity criteria of these measurements are limited. The present study therefore aims to evaluate the reliability of measurements of Achilles- and Patella tendon diameter and in the detection of structural adaptations. Materials and Methods: In 14 healthy, recreationally active subjects both asymptomatic Achilles (AT) and patella tendons (PT) were measured twice by two examiners in a test-retest design. Besides the detection of anteroposterior (a.p.-) and mediolateral (m.l.-) diameters, areas of hypoechogenicity and neovascularisation were registered. Data were analysed descriptively with calculation of test-retest variability (TRV), intraclass-correlation coefficient (ICC) and Bland and Altman's plots with bias and 95\% limits of agreement (LOA). Results: Intra- and interrater differences of AT- and PT-a.p.-diameter varied from 0.2 - 1.2 mm, those of AT- and PT-m.l-diameter from 0.7-5.1 mm. Areas of hypoechogenicity were visible in 24\% of the tendons, while 15\% showed neovascularisations. Intrarater AT-a.p.-diameters showed sparse deviations (TRV 4.5-7.4\%; ICC 0.60-0.84; bias -0.05-0.07 mm; LOA-0.6-0.5 to -1.1 - 1.0 mm), while interrater AT- and PT-m.l.-diameters were highly variable (TRV 13.7-19.7\%; ICC 0.11-0.20; bias -1.4-4.3 mm; LOA-5.5-2.7 to -10.5 - 1.9 mm). Conclusion: Our results suggest that the measurement of AT- and PT-a.p.-diameters is a reliable parameter. In contrast, reproducibility of AT- and PT-m.l.-diameters is questionable. The study corroborates the presence of hypoechogenicity and neovascularisation in asymptomatic tendons.}, language = {de} }