Changes in Tissue-Specific Fatty Acid Composition of the Freshwater Alewife (Alosa pseudoharengus) in Response to Temperature

Ectotherms are known to alter the composition of the cell membrane in response to changes in environmental temperature. Tissue-specific fatty acid composition in the alewife (Alosa pseudoharengus) was examined in response to both warm and cold temperature challenges administered over an approximate one month period. Gill, muscle, and liver tissues were analyzed prior to the start of the temperature challenge (initial), following the temperature challenges (survivors), and on those fish that did not survive the temperature challenges (mortalities). Significant differences were found between fatty acid composition of initial fish and survivors for membrane-incorporated fatty acids (polar) and for stored fatty acids (neutral). In the cold challenge, gill tissues exhibited significant remodeling in membrane fatty acids (polar), including decreases in palmitic acid and saturated fatty acids and increases in highly unsaturated fatty acids. In the warm challenge, significant increases in saturated fatty acids were observed in polar lipids of muscle and liver tissue. Notably, a large increase in palmitic acid (C16:0) was observed in response to increased temperatures. Fatty acid profiles of fish that died during the cold challenge exhibited significantly higher levels of C16:0 in muscle tissues when compared to survivors. The observed changes in membrane (polar) fatty acids would be expected to promote appropriate membrane fluidity in response to temperature. Results of this study suggest that freshwater alewives respond to temperature challenges in accordance with what would be predicted by homeoviscous adaptation, although the pattern and extent of changes in response to temperature differed greatly among the tested tissues

Development and evaluation of a manual segmentation protocol for deep grey matter in multiple sclerosis: Towards accelerated semi-automated references

Background: Deep grey matter (dGM) structures, particularly the thalamus, are clinically relevant in multiple sclerosis (MS). However, segmentation of dGM in MS is challenging; labeled MS-specific reference sets are needed for objective evaluation and training of new methods. Objectives: This study aimed to (i) create a standardized protocol for manual delineations of dGM; (ii) evaluate the reliability of the protocol with multiple raters; and (iii) evaluate the accuracy of a fast-semi-automated segmentation approach (FASTSURF). Methods: A standardized manual segmentation protocol for caudate nucleus, putamen, and thalamus was created, and applied by three raters on multi-center 3D T1-weighted MRI scans of 23 MS patients and 12 controls. Intra- and inter-rater agreement was assessed through intra-class correlation coefficient (ICC); spatial overlap through Jaccard Index (JI) and generalized conformity index (CIgen). From sparse delineations, FASTSURF reconstructed full segmentations; accuracy was assessed both volumetrically and spatially. Results: All structures showed excellent agreement on expert manual outlines: intra-rater JI > 0.83; inter-rater ICC ≥ 0.76 and CIgen ≥ 0.74. FASTSURF reproduced manual references excellently, with ICC ≥ 0.97 and JI ≥ 0.92. Conclusions: The manual dGM segmentation protocol showed excellent reproducibility within and between raters. Moreover, combined with FASTSURF a reliable reference set of dGM segmentations can be produced with lower workload

Prehabilitation in patients undergoing colorectal surgery fails to confer reduction in overall morbidity : results of a single-center, single-blinded, randomized controlled trial

Objective: Patients undergoing major surgery are prone to a functional decline due to the impairment of muscle, cardiorespiratory and neurological function as a response to surgical stress. Currently, there are solely weak recommendations in the ERAS protocol regarding the role of preoperative physical activity and prehabilitation in patients undergoing colorectal surgery. Studies in heterogenous cohorts showed contradictory results regarding the impact of prehabilitation on the reduction of postoperative complications. This randomized controlled trial assesses the impact of prehabilitation on postoperative complications in patients undergoing colorectal surgery within an ERAS protocol. Methods: Between July 2016 and June 2019, a single-center, single-blinded , randomized controlled trial designed to test whether physiotherapeutic prehabilitation vs. normal physical activities prior to colorectal surgery may decrease morbidity within a stringent ERAS protocol was carried out. The primary endpoint was postoperative complications assessed by Comprehensive Complications Index (CCI®). Primary and secondary endpoints for both groups were analyzed and compared. Results: A total of 107 patients (54 in the pERACS and 53 in the control cohort) were included in the study and randomized. Dropout rate was 4.5% (n = 5). Mean age (SD) in the control cohort was 65 (29–86) and 66 (24–90) years in pERACS cohort. The pERACS cohort contained more female patients (40% vs. 55%, p = 0.123) and a higher percentage of colorectal adenocarcinoma (32% vs. 23%, p = 0.384) although not significant. Almost all patients underwent minimally invasive surgery in both cohorts (96% vs 98%, p = 1.000). There was no between-cohort difference in the primary outcome measure 30-day Comprehensive Complications Index (15 [0 – 49] vs. 18 [0 – 43], p = 0.059). Secondary outcome as complications assessed according to Clavien-Dindo, length of hospital stay, reoperation rate and mortality showed no difference between both cohorts. Conclusion: Routine physiotherapeutic prehabilitation cannot be recommended for patients undergoing colorectal surgery within an ERAS protocol (Grade A recommendation). To eliminate other confounders like geographical difference or difference in surgical technique, further multicenter RCTs are needed