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Kremer, Thomas

https://orcid.org/0000-0002-5999-5183

Mayo Clinic

Roche (Switzerland)

Citations 4

Multicenter Assessment of Immunohistochemical Methods for Pathological Alpha-Synuclein in Sigmoid Colon of Autopsied Parkinson’s Disease and Control Subjects
Beach, Thomas G., Corbillé, Anne-Gaëlle, Letournel, Franck , Kordower, Jeffrey H. , Kremer, Thomas , Intorcia, Anthony J., Hentz, Joseph G. , Sue, Lucia I., Walker, Jessica E. , Kordower, Jeffrey H. , Hentz, Joseph, Muñoz, David G. , Adler, Charles H. , Serrano, Geidy E. , Derkinderen, Pascal

Journal of Parkinson’s Disease | September 2, 2016 | Volume: 6 | Issue: 4 | Pages: 761-770

10.3233/jpd-160888 Get It

Background: Conflicting results from studies of Lewy-type α−synucleinopathy (LTS) in colonic biopsies of subjects with Parkinson’s disease (PD) prompted a two-part multicenter assessment. The first assessment, now published (Acta Neuropathol Commun 4 : 35, 2016), examined archived colonic biopsies and found that none of the tested methods was adequately sensitive or specific. Objective: As the amount of nervous tissue in typical colonic biopsies may be insufficient, and the clinical diagnosis of PD not completely accurate, the objective of the current study was to use instead full-thickness sections of sigmoid colon from autopsy-proven PD and normal subjects. Methods: Seven different immunohistochemical (IHC) methods were used, employing five different primary antibodies and four different combinations of epitope exposure and signal development protocols. Specific staining was defined as being restricted to morphological features consistent with neuronal elements. Stained slides from each subject were independently categorized as being positive or negative for LTS, and their density semi-quantitatively graded, by four raters blinded to diagnosis. Results: Agreement and mean diagnostic performance varied markedly between raters. With the two most accurate raters, 5 methods achieved diagnostic accuracies of 70% or greater; one method had 100% accuracy and 100% inter-rater agreement. The submucosa had the highest prevalence of pathological LTS staining, followed by the muscularis and mucosa. Conclusions: The major conclusion of this study is that, when sufficient submucosa and LTS is present, and when specific staining is defined as being consistent with neuronal morphology, adequately-trained raters may reliably distinguish PD colon from control using suitable IHC methods.
Free flaps for reconstruction of soft tissue defects in lower extremity: A meta‐analysis on microsurgical outcome and safety
Kremer, Thomas , Hernekamp, Frederick, Harhaus, Leila , Saint‐Cyr, Michel, Hirche, Christoph , Xiong, Lingyun , Gazyakan, Emre , Kneser, Ulrich

Microsurgery | January 5, 2016 | Volume: 36 | Issue: 6 | Pages: 511-524

10.1002/micr.30020 Get It

BackgroundMicrosurgical free flaps for reconstruction of soft tissue defects in lower extremity have evolved into a reliable procedure over last decades; however, there lacked high level of evidence.MethodsA systematic literature research was performed including studies between 2000 and 2014 in English, German, and Chinese (PubMed, EMBASE). Publications were selected applying inclusion/exclusion criteria. Postoperative complications were statistically analyzed with metaprop command of R GUI 3.0.1.ResultsAlltogether 30 articles overlooking 1,397 free flaps were included. The rate of total flap loss was 6.0% (95% confidence interval [CI] = 4.0%–8.0%, PQ (P values of Q statistics) = 0.03); the thrombosis rate was 6.0% (95% CI = 4.0%–9.0%, PQ = 0.01); the hematoma rate was 4.0% (95% CI = 3.0%–5.0%, PQ = 0.79); the partial necrosis rate was 6.0% (95% CI = 4.0%–10.0%, PQ < 0.01); the early infection rate was 4.0% (95% CI = 2.0%–6.0%, PQ = 0.03), and the dehiscence rate was 3.0% (95% CI = 2.0%–5.0%, PQ = 0.12). Reconstruction for diabetic foot may be not associated with a significant increase of procedural risk (Total flap loss rate = 6%, 95% CI = 3.0%–9.0%, PQ = 0.44).ConclusionsMicrosurgical reconstruction of soft tissue defects in the lower extremity reconstruction could be regarded safe and reliable. A standardization of report of perioperative parameters and clinical outcomes is needed. © 2016 Wiley Periodicals, Inc. Microsurgery 36:511–524, 2016.
The influence of vascularization of transplanted processed allograft nerve on return of motor function in rats
Giusti, Guilherme , Lee, Joo‐Yup , Kremer, Thomas , Friedrich, Patricia F. , Shin, Alexander Y. , Friedrich, Patricia , Bishop, Allen T. , Shin, Alexander Y

Microsurgery | December 30, 2014 | Volume: 36 | Issue: 2 | Pages: 134-143

10.1002/micr.22371 Get It

Processed nerve allografts have become an alternative to repair segmental nerve defects, with results comparable with autografts regarding sensory recovery; however, they have failed to reproduce comparable motor recovery. The purpose of this study was to determine how revascularizaton of processed nerve allograft would affect motor recovery. Eighty‐eight rats were divided in four groups of 22 animals each. A unilateral 10‐mm sciatic nerve defect was repaired with allograft (group I), allograft wrapped with silicone conduit (group II), allograft augmented with vascular endothelial growth factor (group III), or autograft (group IV). Eight animals from each group were sacrificed at 3 days, and the remaining animals at 16 weeks. Revascularization was evaluated by measuring the graft capillary density at 3 days and 16 weeks. Measurements of ankle contracture, compound muscle action potential, tibialis anterior muscle weight and force, and nerve histomorphometry were performed at 16 weeks. All results were normalized to the contralateral side. The results of capillary density at 3 days were 0.99% ± 1.3% for group I, 0.33% ± 0.6% for group II, 0.05% ± 0.1% for group III, and 75.6% ± 45.7% for group IV. At 16 weeks, the results were 69.9% ± 22.4% for group I, 37.0% ± 16.6% for group II, 84.6% ± 46.6% for group III, and 108.3% ± 46.8% for group IV. The results of muscle force were 47.5% ± 14.4% for group I, 21.7% ± 13.5% for group II, 47.1% ± 7.9% for group III, and 54.4% ± 10.6% for group IV. The use of vascular endothelial growth factor in the fashion used in this study improved neither the nerve allograft short‐term revascularization nor the functional motor recovery after 16 weeks. Blocking allograft vascularization from surrounding tissues was detrimental for motor recovery. The processed nerve allografts used in this study showed similar functional motor recovery compared with that of the autograft. © 2014 Wiley Periodicals, Inc. Microsurgery 36:134–143, 2016.