title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=641 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Distorted body schema after mastectomy with immediate breast reconstruction: a 4-month follow up study link: https://peerj.com/articles/14157 last-modified: 2022-10-03 description: BackgroundAfter breast cancer, some patients report residual pain-related upper limb disability without physical impairment. Although pain and altered proprioception are known to affect the working body schema (WBS), there is little available evidence investigating the WBS of breast cancer survivors (BrCS). WBS—body representations in the brain—affect the “neuromatrix” that modulates pain sensitivity and the threshold for threatening stimuli. The aim of this study was to investigate whether WBS was disrupted after mastectomy with immediate breast reconstruction (IBR) for breast cancer and whether pain and proprioceptive changes affected WBS.MethodsThirty-five BrCS participated in the 4-month follow-up study. They were observed at 1 and 4 months postoperatively. The main outcome measures were the left right judgement test (LRJT) results, absolute angle error, pectoralis minor length index (PMI), pain, and Quick-Disabilities of the Arm, Shoulder, and Hand (Q-DASH) score. They were measured at each observation, and parametric tests were performed to identify the nature of WBS.ResultsBoth the reaction time and accuracy of the hand LRJT were poorer than those of the foot and back LRJT (p < 0.001). The hand LRJT reaction time and accuracy were unchanged over the total follow-up period (p = 0.77 and p = 0.47, respectively). There was a weak correlation between the LRJT reaction time and PMI (r = −0.26, p = 0.07), pain severity (r = 0.37, p = 0.02), and Q-DASH score (r = 0.37, p = 0.02). There was also a weak correlation between LRJT accuracy and Q-DASH score (r = −0.31, p = 0.04). The LRJT accuracy of BrCS who underwent surgery on their dominant side was higher than that of BrCS who underwent surgery on their non-dominant side (p = 0.002). Regression analysis found a weak but significant relationship between the early hand LRJT results and late pain severity (adjusted R2 = 0.179, p = 0.007). A similar relationship was found between early hand LRJT results and Q-DASH score (adjusted R2 = 0.099, p = 0.039).ConclusionTo the best of our knowledge, this is the first study providing the nature of WBS after mastectomy with IBR. In this population, it is necessary to postoperatively preserve WBS integrity for pain and upper limb disability. creator: Asall Kim creator: Eun Joo Yang creator: Myungki Ji creator: Jaewon Beom creator: Chunghwi Yi uri: https://doi.org/10.7717/peerj.14157 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Kim et al. title: An in silico study of how histone tail conformation affects the binding affinity of ING family proteins link: https://peerj.com/articles/14029 last-modified: 2022-09-30 description: BackgroundDue to its intrinsically disordered nature, the histone tail is conformationally heterogenic. Therefore, it provides specific binding sites for different binding proteins or factors through reversible post-translational modifications (PTMs). For instance, experimental studies stated that the ING family binds with the histone tail that has methylation on the lysine in position 4. However, numerous complexes featuring a methylated fourth lysine residue of the histone tail can be found in the UniProt database. So the question arose if other factors like the conformation of the histone tail affect the binding affinity.MethodsThe crystal structure of the PHD finger domain from the proteins ING1, ING2, ING4, and ING5 are docked to four histone H3 tails with two different conformations using Haddock 2.4 and ClusPro. The best four models for each combination are selected and a two-sample t-test is performed to compare the binding affinities of helical conformations vs. linear conformations using Prodigy. The protein-protein interactions are examined using LigPlot.ResultsThe linear histone conformations in predicted INGs-histone H3 complexes exhibit statistically significant higher binding affinity than their helical counterparts (confidence level of 99%). The outputs of predicted models generated by the molecular docking programs Haddock 2.4 and ClusPro are comparable, and the obtained protein-protein interaction patterns are consistent with experimentally confirmed binding patterns.ConclusionThe results show that the conformation of the histone tail is significantly affecting the binding affinity of the docking protein. Herewith, this in silico study demonstrated in detail the binding preference of the ING protein family to histone H3 tail. Further research on the effect of certain PTMs on the final tail conformation and the interaction between those factors seem to be promising for a better understanding of epigenetics. creator: Nadir Gül creator: Ahmet Yıldız uri: https://doi.org/10.7717/peerj.14029 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2022 Gül and Yıldız title: MicroRNA-21 as a potential biomarker for detecting esophageal carcinoma in Asian populations: a meta-analysis link: https://peerj.com/articles/14048 last-modified: 2022-09-30 description: BackgroundMicroRNA-21 (miR-21) is significantly expressed in a variety of cancers and could be used as a tumor biomarker. However, the results are varied, and no studies on the diagnostic usefulness of miR-21 in Asian esophageal cancer (EC) patients have been published. This meta-analysis was aimed at exploring whether miR-21 can be used as a diagnostic marker and assessing its effectiveness.MethodsThe relevant literature was identified in six main databases: Ovid MEDLINE, PsycINFO, PubMed MEDLINE, Embase, Web of Science, and the Cochrane Library. Two researchers independently selected the literature based on the inclusion and exclusion criteria, extracted data, and evaluated the risk of bias. The meta-analysis was carried out using Review Manager 5.4, Meta-Disc 1.4 and STATA 15.1 software. In the end, 987 patients from 12 different studies were included. Quality evaluation of diagnostic accuracy studies 2 (QUADAS—2) was used to examine the risk of bias.ResultsThe pooled sensitivity (SEN) was 0.72 (95% CI [0.69–0.75]), the pooled specificity (SPE) was 0.78 (95% CI [0.75–0.81]), the pooled positive likelihood ratio (PLR) was 2.87 (95% CI [2.28–3.59]), the pooled negative likelihood ratio (NLR) was 0.36 (95% CI [0.31–0.43]), the pooled diagnostic odds ratio (DOR) was 10.00 (95% CI [7.73–12.95]), and the area under the curve 0.82 (95% CI [0.79–0.85]). A Deeks’ funnel plot shows that there was no publication bias (P = 0.99).ConclusionOur findings suggest miR-21 might be the potential biomarker for detecting EC in Asian populations, with a good diagnostic value. creator: Zheng Han creator: Lingbo Pan creator: Bangjie Lu creator: Huixia Zhu uri: https://doi.org/10.7717/peerj.14048 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Han et al. title: Irradiation with carbon ion beams affects soybean nutritional quality in early generations link: https://peerj.com/articles/14080 last-modified: 2022-09-30 description: As people’s demand for healthy diet increases, improving soybean seed nutritional quality is becoming as important as yield. Carbon ion beam radiation (CIBR) is an effective method to create soybean mutants, and thus breeding cultivars with better seed nutritional quality. In this study, the high-yield soybean line ‘Dongsheng 28’ was used, and three CIBR doses (100, 120, and 140 Gy) were used to explore the characteristics of quality separation and variation in the offspring of early mutant populations. Eleven quality traits, including protein, oil, sucrose, soluble sugar, iron (Fe), manganese (Mn), zinc (Zn), cupper (Cu), daidzin, glycitin, and genistin concentrations were analyzed in the M2 and M3 generations. The results revealed that the range of protein and oil concentration of all three CIBR doses changed by 38.5–42.9% and 18.8–23.8% in the M2 and M3 generations, respectively, while soluble sugar and sucrose concentrations changed by 48.1–123.4 and 22.7–74.7 mg/g, with significant effects by 140 Gy across the two generations. Therefore, around the optimum range, a higher CIBR dose is better for high protein, oil, and sugar varieties selection. In general, irradiation raised isoflavone concentrations, but 140 Gy had an inhibitory effect on isoflavone concentrations in the M3 generation. Although a variety could not be released in the M2 or M3 generation, the results of this study have important guiding significance for the targeted cultivation of specific nutritional quality materials. For instance, a lower irradiation dose is preferable when breeding targets are higher isoflavones and Mn concentrations. It is essential to increase the irradiation dose if the breeding targets contain high levels of protein, oil, sucrose, soluble sugars, Fe, Zn, and Cu. creator: Changkai Liu creator: Xue Wang creator: Yansheng Li creator: Heng Chen creator: Qiuying Zhang creator: Xiaobing Liu uri: https://doi.org/10.7717/peerj.14080 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Liu et al. title: Rapid restructurization of conformationally-distinct alpha-synuclein amyloid fibrils at an elevated temperature link: https://peerj.com/articles/14137 last-modified: 2022-09-30 description: Protein aggregation in the form of amyloid fibrils is linked with the onset and progression of more than 30 amyloidoses, including multiple neurodegenerative disorders, such as Alzheimer’s or Parkinson’s disease. Despite countless studies and years of research, the process of such aggregate formation is still not fully understood. One peculiar aspect of amyloids is that they appear to be capable of undergoing structural rearrangements even after the fibrils have already formed. Such a phenomenon was reported to occur in the case of alpha-synuclein and amyloid beta aggregates after a long period of incubation. In this work, we examine whether incubation at an elevated temperature can induce the restructurization of four different conformation alpha-synuclein amyloid fibrils. We show that this structural alteration occurs in a relatively brief time period, when the aggregates are incubated at 60 °C. Additionally, it appears that during this process multiple conformationally-distinct alpha-synuclein fibrils all shift towards an identical secondary structure. creator: Mantas Ziaunys creator: Andrius Sakalauskas creator: Kamile Mikalauskaite creator: Vytautas Smirnovas uri: https://doi.org/10.7717/peerj.14137 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Ziaunys et al. title: Progressive overload without progressing load? The effects of load or repetition progression on muscular adaptations link: https://peerj.com/articles/14142 last-modified: 2022-09-30 description: BackgroundProgressive overload is a principle of resistance training exercise program design that typically relies on increasing load to increase neuromuscular demand to facilitate further adaptations. However, little attention has been given to another way of increasing demand—increasing the number of repetitions.ObjectiveThis study aimed to compare the effects of two resistance training programs: (1) increasing load while keeping repetition range constant vs (2) increasing repetitions while keeping load constant. We aimed to compare the effects of these programs on lower body muscle hypertrophy, muscle strength, and muscle endurance in resistance-trained individuals over an 8-week study period.MethodsForty-three participants with at least 1 year of consistent lower body resistance training experience were randomly assigned to one of two experimental, parallel groups: A group that aimed to increase load while keeping repetitions constant (LOAD: n = 22; 13 men, nine women) or a group that aimed to increase repetitions while keeping load constant (REPS: n = 21; 14 men, seven women). Subjects performed four sets of four lower body exercises (back squat, leg extension, straight-leg calf raise, and seated calf raise) twice per week. We assessed one repetition maximum (1RM) in the Smith machine squat, muscular endurance in the leg extension, countermovement jump height, and muscle thickness along the quadriceps and calf muscles. Between-group effects were estimated using analyses of covariance, adjusted for pre-intervention scores and sex.ResultsRectus femoris growth modestly favored REPS (adjusted effect estimate (CI90%), sum of sites: 2.8 mm [−0.5, 5.8]). Alternatively, dynamic strength increases slightly favored LOAD (2.0 kg [−2.4, 7.8]), with differences of questionable practical significance. No other notable between-group differences were found across outcomes (muscle thicknesses, <1 mm; endurance, <1%; countermovement jump, 0.1 cm; body fat, <1%; leg segmental lean mass, 0.1 kg), with narrow CIs for most outcomes.ConclusionBoth progressions of repetitions and load appear to be viable strategies for enhancing muscular adaptations over an 8-week training cycle, which provides trainers and trainees with another promising approach to programming resistance training. creator: Daniel Plotkin creator: Max Coleman creator: Derrick Van Every creator: Jaime Maldonado creator: Douglas Oberlin creator: Michael Israetel creator: Jared Feather creator: Andrew Alto creator: Andrew D. Vigotsky creator: Brad J. Schoenfeld uri: https://doi.org/10.7717/peerj.14142 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Plotkin et al. title: Exercise interventions in migraine patients: a YouTube content analysis study based on grades of recommendation link: https://peerj.com/articles/14150 last-modified: 2022-09-30 description: BackgroundMigraine is the second leading cause of disability worldwide, engendering a high economic cost in developed countries. The adverse events related to pharmacological treatment use have increased interest in non-pharmacological interventions such as exercise. YouTube offers a public source of information for migraine patients regarding exercise interventions for migraine improvement. However, this information has not been validated to ensure the quality and validity of its content.ObjectiveThis qualitative content analysis study aims to review and evaluate YouTube videos regarding exercise for migraine.MethodsA systematic review of the current evidence regarding exercise for migraine was performed to establish evidence classification and grades of recommendation with the Scottish Intercollegiate Guidelines Network tool. The data sources were PubMed, PEDro, Cochrane, EBSCO, Google Scholar and Web of Science. The quality of YouTube videos on exercise in migraine was reviewed using the Global Quality Scale and DISCERN scale. Finally, the classification in grades of recommendation was used to evaluate the included videos in terms of the various exercise modalities.ResultsThe classification into recommendation grades showed a grade B for aerobic exercise, yoga and changes in lifestyle behavior regarding exercise. A total of 129 videos were included. The healthcare and exercise professional authors produced higher quality videos with a significant statistical difference, although the alternative therapists and patients’ videos had a greater impact and a higher viewership based on correlation analysis. The evaluation of the videos based on the recommendation grades could only include 90 videos. 71% of these videos showed a B grade of recommendation, which corresponded to fewer than half of the total included videos.ConclusionsYouTube needs higher quality videos on exercise for migraine, and healthcare and exercise professional authors need to improve their scoping strategies to acquire more views. The authors of YouTube videos should have better access to the best current evidence regarding exercise interventions in migraine. creator: Álvaro Reina-Varona creator: Borja Rodríguez de Rivera-Romero creator: Carlos Donato Cabrera-López creator: José Fierro-Marrero creator: Irene Sánchez-Ruiz creator: Roy La Touche uri: https://doi.org/10.7717/peerj.14150 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Reina-Varona et al. title: Optimal selection of COVID-19 vaccination sites in the Philippines at the municipal level link: https://peerj.com/articles/14151 last-modified: 2022-09-30 description: In this work, we present an approach to determine the optimal location of coronavirus disease 2019 (COVID-19) vaccination sites at the municipal level. We assume that each municipality is subdivided into smaller administrative units, which we refer to as barangays. The proposed method solves a minimization problem arising from a facility location problem, which is formulated based on the proximity of the vaccination sites to the barangays, the number of COVID-19 cases, and the population densities of the barangays. These objectives are formulated as a single optimization problem. As an alternative decision support tool, we develop a bi-objective optimization problem that considers distance and population coverage. Lastly, we propose a dynamic optimization approach that recalculates the optimal vaccination sites to account for the changes in the population of the barangays that have completed their vaccination program. A numerical scheme that solves the optimization problems is presented and the detailed description of the algorithms, which are coded in Python and MATLAB, are uploaded to a public repository. As an illustration, we apply our method to determine the optimal location of vaccination sites in San Juan, a municipality in the province of Batangas, in the Philippines. We hope that this study may guide the local government units in coming up with strategic and accessible plans for vaccine administration. creator: Kurt Izak Cabanilla creator: Erika Antonette T. Enriquez creator: Arrianne Crystal Velasco creator: Victoria May P. Mendoza creator: Renier Mendoza uri: https://doi.org/10.7717/peerj.14151 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Cabanilla et al. title: Mode-specific effects of concentric and eccentric isokinetic training of the hamstring muscle at slow angular velocity on the functional hamstrings-to-quadriceps ratio-a randomized trial link: https://peerj.com/articles/13842 last-modified: 2022-09-29 description: BackgroundPrevious studies have examined the mode specificity of eccentric and concentric isokinetic training, but have reported conflicting results. Few studies have reported that eccentric and concentric isokinetic training are mode-specific, i.e., they will increase only the eccentric or concentric strength, respectively. Other studies have reported that mode specificity does not exist. Therefore, this study aimed to assess the mode-specific effects of eccentric and concentric isokinetic training of the hamstring muscle at slow angular velocity on eccentric peak torque of the hamstring (PTecc), concentric peak torque of the quadriceps (PTcon), acceleration time of the hamstring (AThams) and quadriceps (ATquad), deceleration time of the hamstring (DThams) and quadriceps (DTquad), time to peak torque of the hamstring (TPThams) and quadriceps (TPTquad), and functional Hamstring-to-Quadriceps ratio (PTecc/PTcon).SubjectsA total of 30 participants were randomly divided into eccentric and concentric groups.MethodsTwo groups pre-test-post-test experimental design was used. In the eccentric and concentric groups, eccentric and concentric isokinetic training of hamstring muscle was performed respectively, at an angular velocity of 60°/s for 6 weeks duration. PTecc, PTcon, AThams, ATquad, DThams, DTquad, TPThams, TPTquad, and PTecc/PTcon were measured before and after the completion of training.ResultsIn the eccentric group, a significant difference (p < 0.05) was observed in PTecc (increased by 21.55%), AThams (decreased by 42.33%), ATquad (decreased by 28.74%), and PTecc/PTcon (increased by 17.59%). No significant difference (p > 0.05) was observed in PTcon, TPThams, TPTquad, DThams, and DTquad. In the concentric group, a significant difference (p < 0.05) was observed in PTecc (increased by 12.95%), AThams (decreased by 27.38%) ATquad (decreased by 22.08%), DTquad (decreased by 26.86%), and PTecc/PTcon (increased by 8.35%). No significant difference (p > 0.05) was observed in PTquad, TPThams, TPTquad, and DThams. Between-group analysis revealed a significant difference (p < 0.05) only in TPTquad; otherwise, in the rest of the parameters, no significant difference (p > 0.05) was observed.ConclusionsBoth eccentric and concentric isokinetic training of the hamstring for 6 weeks increased PTecc, PTecc/PTcon, and decreased AThams and ATquad. The effects of eccentric and concentric isokinetic training of the hamstring on PTecc, PTecc/PTcon, AThams, and ATquad were not mode specific. creator: Kushla Nand Sharma creator: Nishat Quddus creator: Unaise Abdul Hameed creator: Sohrab Ahmad Khan creator: Anita Kumari creator: Ahmad H. Alghadir creator: Masood Khan uri: https://doi.org/10.7717/peerj.13842 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2022 Sharma et al. title: The preclinical pharmacological study of a novel intravenous anesthetic, ET-26 hydrochloride, in aged rats link: https://peerj.com/articles/13995 last-modified: 2022-09-29 description: BackgroundET-26 hydrochloride (ET-26HCl) is a novel analogue of etomidate approved for clinical trials. However, all results from recent studies were accomplished in young adult animals. The objective of this study was to evaluate the efficacy and safety of ET-26HCl in aged rats.MethodsAged Sprague-Dawley rats were randomly divided into three groups (three males and three females in each group) were given dose of two-fold of median effective dose (ED50) of ET-26HCl, etomidate and propofol: the measurements of loss of the righting reflex (LORR) and cardiovascular and respiratory function after injection at the two-fold dose of the median effective dose were used for evaluation of effectiveness and safety, and the modified adrenocorticotropic hormone-stimulation experiment was used to evaluate the inhibition effect of the drugs on the synthesis of adrenal cortical hormones.ResultsThere was no significant difference in the onset time among propofol, etomidate and ET-26HCl. The duration of propofol (850.5 ± 77.4 s) was significantly longer than that caused by etomidate (489.8 ± 77.0 s, p = 0.007) and ET-26HCl (347.3 ± 49.0 s, p = 0.0004). No significant difference was observed in the time to stand and normal activity among drugs. A total of 66.7% of rats in the ET-26HCl group were evaluated to have mild hematuria. Then, etomidate and ET-26HCl had a milder blood pressure inhibition effect than propofol. Apnea was observed in all rats administered propofol and the duration for this side effect was 45.0 ± 9.0 s. For etomidate and ET-26HCl, no apnea was observed. No other clinical signs of side-effect were observed, and no rats died. No significant difference was observed in corticosterone concentrations between ET-26HCl and solvent group. However, rats administered etomidate had lower corticosterone concentrations than those administered ET-26HCl at 15, 30, and 60 min.ConclusionsOur results indicate ET-26HCl in aged rats is an effective sedative-hypnotic with stable myocardial and respiratory performance and also have mild adrenocortical suppression. Thus, these findings increase the potential for the clinical use of ET-26HCl in the elderly population. creator: Pan Chang creator: YongWei Su creator: DeYing Gong creator: Yi Kang creator: Jin Liu creator: YuJun Zhang creator: Wen-sheng Zhang uri: https://doi.org/10.7717/peerj.13995 license: https://creativecommons.org/licenses/by-nc/4.0 rights: ©2022 Chang et al.