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1.
Food Chem ; 458: 140283, 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38959796

RÉSUMÉ

Apoptosis was associated with decreased sensory quality attributes of fish during postmortem storage. Based on cytochrome c (cyt-c) release plays a crucial role in apoptosis, the study aims to investigate the factors regulating cyt-c release and whether cyt-c acts as an endogenous pro-oxidant to trigger lipid oxidation. Within 12 h postmortem, dramatic changes in the intramuscular environment (glycogen from 1.57 mg/g to 0.65 mg/g; ATP reduced by 92.91%; pH value reaching the lowest (pH = 7.14)) and the mitochondrial environment (accumulation of mitochondrial ROS and Ca2+ levels) are induced mitochondrial swelling and opening of the MPTP (increased 34.35% and 31.91%), leading to the release of cyt-c from the mitochondria into the cytoplasm and the activation of caspase-3. This leads to lipid oxidation and degradation of myofibrillar proteins, accelerating quality deterioration in color and texture. The results suggest that cyt-c is involved in lipid oxidation during postmortem through the apoptotic mitochondrial pathway.

2.
J Sports Sci Med ; 23(2): 305-316, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38841633

RÉSUMÉ

This study compared the inter-individual variability in adaptive responses to six weeks of small-sided games (SSG) and short sprint interval training (sSIT) in young basketball players. Thirty well-trained young athletes (age: 16.4 ± 0.6 years; stature: 190 ± 8.4 cm; weight: 84.1 ± 8.2 kg) voluntarily participated and were randomly assigned to SSG (3 sets of 5 min 3v3 on full length (28 m) and half-width (7.5 m) court, with 2 minutes of passive recovery in-between), sSIT (3 sets of 12 × 5 s sprinting with 20 s recovery between efforts and 2 min of rest between sets), or CON (routine basketball-specific technical and tactical drills) groups, each of ten. Before and after the training period, participants underwent a series of laboratory- and field-based measurements to evaluate their maximum oxygen uptake (V̇O2max), first and second ventilatory threshold (VT1 and VT2), oxygen pulse, peak and average power output (PPO and APO), linear speed, change of direction (COD), countermovement jump (CMJ), and vertical jump (VJ). Both SSG and sSIT sufficiently stimulated adaptive mechanisms involved in enhancement of the mentioned variables (p < 0.05). However, sSIT resulted in lower residuals in percent changes in V̇O2max (p = 0.02), O2pulse (p = 0.005), VT1 (p = 0.001), PPO (p = 0.03), and linear speed (p = 0.01) across athletes compared to the SSG. Moreover, sSIT resulted in more responders than SSG in V̇O2max (p = 0.02, φ = 0.500), O2pulse (p = 0.003, φ = 0.655), VT1 (p = 0.003, φ = 0.655), VT2 (p = 0.05, φ = 0.436), and linear speed (p = 0.05, φ = 0.420). Our results indicate that sSIT creates a more consistent level of mechanical and physiological stimulus than SSG, potentially leading to more similar adaptations across team members.


Sujet(s)
Adaptation physiologique , Performance sportive , Basketball , Consommation d'oxygène , Humains , Basketball/physiologie , Adolescent , Performance sportive/physiologie , Consommation d'oxygène/physiologie , Mâle , Entrainement fractionné de haute intensité/méthodes , Course à pied/physiologie
3.
Heliyon ; 9(12): e22370, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-38076164

RÉSUMÉ

The Huajiying Formation (135.4-128.7 Ma) of the northern Hebei represents the early stage of the Early Cretaceous Jehol Biota in China, yielding many kinds of vertebrates. The only known pterosaur specimen was incomplete and assigned to the Ornithocheiroidea. Here we report a more complete pterosaur specimen, assigned to the Ctenochasmatidae. A new taxon is established on two autapomorphies: a large pneumatic foramen present on the ventral surface of the proximal end of the first wing phalanx; and coracoid lacking an expansion at its contact with the scapula, as well as the following combination of characteristics: subsquare sternal plate; coracoid having an extremely concave articulation with a posterior expansion; humerus without a tubercle on the proximal margin between the deltopectoral crest and the head; humerus slightly longer than the wing metacarpal; and the first and third wing phalanges equal in length. The relative thicknesses of bone walls are investigated among pterosaurs in three ways. The overall distribution of R/t ratios shows that most non-pterodactyloids, archaeopterodactyloids, and dsungaripterids have smaller R/t ratios than other groups. Relatively thick bone walls are not unique for the Dsungaripteridae as previously thought, and the humerus and radius of dsungaripterids have thinner walls than other bones. The feature of small R/t ratios is plesiomorphic and the thin-walled humerus and radius of dsungaripterids were evolved to meet the need of the flight, not for frequent take-off and landing as previously thought.

4.
PeerJ ; 11: e15877, 2023.
Article de Anglais | MEDLINE | ID: mdl-37576500

RÉSUMÉ

Objectives: Jumping ability has been identified as a key factor that influences the performance of badminton athletes. Autoregulatory progressive resistance exercise (APRE) and velocity-based resistance training (VBRT) are commonly used approaches to enhance muscle strength and have been shown to accurately monitor the development of explosive power to improve jumping ability. This study aims to investigate the effects of APRE and VBRT on badminton athletes' jumping ability and to provide practical insights into improving their jumping performance during competitions. Methods: Upon completing familiarization and pretesting, 18 badminton athletes were included and completed the training intervention (age, 21.4 ± 1.4 years; stature, 170.1 ± 7.3 cm; body mass, 65.9 ± 12 kg); they were randomly divided into the APRE group (n = 9) and VBRT group (n = 9). Jumping performance was assessed during the countermovement jump (CMJ), squat jump (SJ), and drop jump (DJ) via SmartJump, with CMJ 's and SJ's jump height, eccentric utilization ratio (EUR), and reactive strength index (RSI). All participants then completed a 4-week in-season resistance training intervention. Results: (1) The results of the within-group indicated that only the CMJ (pre: 41.56 ± 7.84 vs post: 43.57 ± 7.85, p < 0.05) of the APRE group had significant differences, whereas the SJ, EUR, and RSI were not significantly different (p > 0.05). (2) The results of the intergroups revealed that all indicators had no significant differences (p > 0.05), but APRE had a moderate effect size on the improvement of the CMJ (η2 = 0.244) and EUR (η2 = 0.068) when compared with VBRT. Conclusions: The results showed that, compared to VBRT, APRE can effectively improve the performance of the reactive athletes' lower limb explosive power in the CMJ in a shorter period of time. The findings indicate that APRE may be useful for coaches seeking to improve the CMJ performance of athletes in the short term.


Sujet(s)
Sports de raquette , Entraînement en résistance , Adulte , Humains , Jeune adulte , Athlètes , Exercice physique , Force musculaire/physiologie , Entraînement en résistance/méthodes
5.
Crit Rev Food Sci Nutr ; : 1-22, 2023 Jun 19.
Article de Anglais | MEDLINE | ID: mdl-37335143

RÉSUMÉ

Aquatic animals are viewed as a good source of healthy lipids. Although drying is an effective method for the preservation of aquatic animal products (AAPs), the whole process is accompanied by lipid oxidation. This article reviews the main mechanism of lipid oxidation in the drying process. It also summarizes the effects of lipid oxidation on the quality of dried aquatic animal products (DAAPs), including nutrients, color, flavor, and hazard components, especially for those harmful aldehydes and heterocyclic amines. In addition, it concluded that moderate lipid oxidation contributes to improving the quality of products. Still, excessive lipid oxidation produces hazardous substances and induces health risks. Hence, to obtain high-quality DAAPs, some effective control technologies to promote/prevent lipid oxidation are introduced and deeply discussed, including salting, high-pressure processing, irradiation, non-thermal plasma technology, defatting treatments, antioxidants, and edible coating. A systematic review of the effect of lipid oxidation on quality attributes and control technologies in DAAPs is presented, and some perspectives are made for future research.

6.
Nat Ecol Evol ; 7(7): 1131-1140, 2023 07.
Article de Anglais | MEDLINE | ID: mdl-37308704

RÉSUMÉ

The amniotic egg with its complex fetal membranes was a key innovation in vertebrate evolution that enabled the great diversification of reptiles, birds and mammals. It is debated whether these fetal membranes evolved in eggs on land as an adaptation to the terrestrial environment or to control antagonistic fetal-maternal interaction in association with extended embryo retention (EER). Here we report an oviparous choristodere from the Lower Cretaceous period of northeast China. The ossification sequence of the embryo confirms that choristoderes are basal archosauromorphs. The discovery of oviparity in this assumed viviparous extinct clade, together with existing evidence, suggests that EER was the primitive reproductive mode in basal archosauromorphs. Phylogenetic comparative analyses on extant and extinct amniotes suggest that the first amniote displayed EER (including viviparity).


Sujet(s)
Lézards , Animaux , Phylogenèse , Viviparité des non mammifères , Reproduction , Mammifères
7.
Front Bioeng Biotechnol ; 11: 1062769, 2023.
Article de Anglais | MEDLINE | ID: mdl-36890909

RÉSUMÉ

Proteins, as gifts from nature, provide structure, sequence, and function templates for designing biomaterials. As first reported here, one group of proteins called reflectins and derived peptides were found to present distinct intracellular distribution preferences. Taking their conserved motifs and flexible linkers as Lego bricks, a series of reflectin-derivates were designed and expressed in cells. The selective intracellular localization property leaned on an RMs (canonical conserved reflectin motifs)-replication-determined manner, suggesting that these linkers and motifs were constructional fragments and ready-to-use building blocks for synthetic design and construction. A precise spatiotemporal application demo was constructed in the work by integrating RLNto2 (as one representative of a synthetic peptide derived from RfA1) into the Tet-on system to effectively transport cargo peptides into nuclei at selective time points. Further, the intracellular localization of RfA1 derivatives was spatiotemporally controllable with a CRY2/CIB1 system. At last, the functional homogeneities of either motifs or linkers were verified, which made them standardized building blocks for synthetic biology. In summary, the work provides a modularized, orthotropic, and well-characterized synthetic-peptide warehouse for precisely regulating the nucleocytoplasmic localization of proteins.

8.
Int J Mol Sci ; 23(24)2022 Dec 10.
Article de Anglais | MEDLINE | ID: mdl-36555320

RÉSUMÉ

Some cephalopods (squids, octopuses, and cuttlefishes) produce dynamic structural colors, for camouflage or communication. The key to this remarkable capability is one group of specialized cells called iridocytes, which contain aligned membrane-enclosed platelets of high-reflective reflectins and work as intracellular Bragg reflectors. These reflectins have unusual amino acid compositions and sequential properties, which endows them with functional characteristics: an extremely high reflective index among natural proteins and the ability to answer various environmental stimuli. Based on their unique material composition and responsive self-organization properties, the material community has developed an impressive array of reflectin- or iridocyte-inspired optical systems with distinct tunable reflectance according to a series of internal and external factors. More recently, scientists have made creative attempts to engineer mammalian cells to explore the function potentials of reflectin proteins as well as their working mechanism in the cellular environment. Progress in wide scientific areas (biophysics, genomics, gene editing, etc.) brings in new opportunities to better understand reflectins and new approaches to fully utilize them. The work introduced the composition features, biochemical properties, the latest developments, future considerations of reflectins, and their inspiration applications to give newcomers a comprehensive understanding and mutually exchanged knowledge from different communities (e.g., biology and material).


Sujet(s)
Decapodiformes , Protéines , Animaux , Protéines/composition chimique , Decapodiformes/composition chimique , Acides aminés , Mammifères/métabolisme
9.
Front Bioeng Biotechnol ; 10: 998194, 2022.
Article de Anglais | MEDLINE | ID: mdl-36312552

RÉSUMÉ

Barnacles are typical fouling organisms strongly adhere to immersed solid substrates by secreting proteinaceous adhesives called cement proteins (CPs). The self-assembly of the CPs forms a permanently bonded layer that binds barnacles to foreign surfaces. However, it is difficult to determine their natural structure and describe their self-assembly properties due to the abundance of cysteines in whole-length CP20. A putative functional motif of Balanus albicostatus CP20 (BalCP20) was identified to present distinctive self-assembly and wet-binding characteristics. Atomic-force microscopy (AFM) and transmission electron microscope (TEM) investigations showed that wildtype BalCP20-P3 formed grain-like spindles, which assembled into fractal-like structures like ears of wheat. SDS-PAGE, AFM, and LSCM showed that DTT treatment opened up disulfide bonds between cysteines and disrupted fractal-like structures. Additionally, these morphologies were abolished when one of the BalCP20-P3 four cysteines was mutated by alanine. Circular dichroism (CD) results suggested that the morphological diversity among BalCP20-P3 and its mutations was related to the proportion of α-helices. Finally, quartz crystal microbalance with dissipation (QCM-D) detected that BalCP20-P3 and its mutations with diverse self-assemblies occupied different affinities. The above results demonstrated that cysteines and disulfide bonds played a crucial role in the self-assembly and wet binding of BalCP20-P3. The work provides new ideas for the underwater bonding of BalCP20 and developing new bionic underwater adhesives.

10.
Front Cell Dev Biol ; 10: 862011, 2022.
Article de Anglais | MEDLINE | ID: mdl-35813206

RÉSUMÉ

Reflectin proteins are natural copolymers consisting of repeated canonical domains. They are located in a biophotonic system called Bragg lamellae and manipulate the dynamic structural coloration of iridocytes. Their biological functions are intriguing, but the underlying mechanism is not fully understood. Reflectin A1, A2, B1, and C were found to present distinguished cyto-/nucleoplasmic localization preferences in the work. Comparable intracellular localization was reproduced by truncated reflectin variants, suggesting a conceivable evolutionary order among reflectin proteins. The size-dependent access of reflectin variants into the nucleus demonstrated a potential model of how reflectins get into Bragg lamellae. Moreover, RfA1 was found to extensively interact with the cytoskeleton, including its binding to actin and enrichment at the microtubule organizing center. This implied that the cytoskeleton system plays a fundamental role during the organization and transportation of reflectin proteins. The findings presented here provide evidence to get an in-depth insight into the evolutionary processes and working mechanisms of reflectins, as well as novel molecular tools to achieve tunable intracellular transportation.

11.
Nucl Med Commun ; 42(1): 63-67, 2021 Jan.
Article de Anglais | MEDLINE | ID: mdl-33044406

RÉSUMÉ

PURPOSE: The aim of this study was to explore the value of skeletal standardized uptake value (SUV) obtained by quantitative single-photon emission computed tomography-computed tomography (SPECT/CT) in differential diagnosis of bone metastases from benign lesions. MATERIALS AND METHODS: Retrospective analysis has been conducted to 51 patients with extraskeletal malignant tumors who underwent whole-body bone scan with quantitative SPECT/CT imaging, and there are no more than three hotspots that were visually detected in the SPECT/CT imaging range. Fifty-one patients were enrolled, including 28 men and 23 women with an average age of 58.8 ± 9.5 (37-77) years. A total of 88 hotspots, including 40 benign lesions and 48 metastatic lesions, and corresponding normal sites were obtained. The region of interest (ROI) of the hotspots was sketched. The ROI of the normal bone of the spinal vertebral body adjacent to the lesions or normal bone of the symmetric side of the lesions of other locations was delineated to obtain the maximum SUV (SUVmax) and the average SUV (SUVave). RESULTS: The SUVmax value of all lesions was 20.73 ± 14.01 (3.90-92.61), and the SUVmax value of the corresponding normal parts was 5.88 ± 2.36 (2.08-12.52). The difference between the two groups was statistically significant (t = 10.343, P < 0.01). The SUVave of all lesions was 8.42 ± 4.81 (37-77), and the SUVave of the corresponding normal sites was 3.10 ± 1.51 (0.65-7.54). The difference between the two groups was statistically significant (t = 11.342, P < 0.01). The SUVmax of metastases was 24.77 ± 16.32 (3.90-92.61), and the SUVmax of benign lesions was 15.89 ± 8.51 (4.68-42.32). The difference between the two groups was statistically significant (t = 3.273, P = 0.002). The SUVave of metastases was 9.09 ± 5.59 (0.81-29.08), and the SUVave of benign lesions was 7.61 ± 3.57 (1.66-17.48). There was no significant difference between the two groups (t = 1.44, P = 0.154). The area under the curve (AUC) values of the SUVmax curves was greater than that of the SUVave curve. AUCs of the SUVmax and SUVave were 0.687 (P = 0.03) and 0.576 (P = 0.223), respectively. SUVmax had greater accuracy for discriminating bone metastasis from benign lesions. Hotspots of the patients with malignant neoplasms in bone SPECT/CT may be discriminated using SUVmax with certain accuracy, and the optimal cutoff value was 17.705. CONCLUSION: The SUVmax of bone metastases was significantly larger than that of benign lesions, and there was no significant difference in SUVave between the two groups. Therefore, the SUVmax has a certain value for the differential diagnosis of metastases from benign lesions.


Sujet(s)
Tumeurs osseuses/imagerie diagnostique , Tumeurs osseuses/secondaire , Os et tissu osseux/métabolisme , Tomographie par émission monophotonique couplée à la tomodensitométrie/normes , Adulte , Sujet âgé , Transport biologique , Tumeurs osseuses/métabolisme , Os et tissu osseux/imagerie diagnostique , Diagnostic différentiel , Femelle , Humains , Mâle , Adulte d'âge moyen , Normes de référence
12.
Ann Nucl Med ; 34(8): 549-558, 2020 Aug.
Article de Anglais | MEDLINE | ID: mdl-32583153

RÉSUMÉ

OBJECTIVE: This retrospective study investigated the performance of whole-body bone scintigraphy combined with SPECT/CT and established a grading diagnostic criterion for bone metastases. METHODS: We summarized signs of whole-body bone imaging combined with SPECT in nuclear medicine and CT signs of corresponding parts. Then we established a diagnostic criterion for bone metastases by using whole-body bone scintigraphy combined with local SPECT/CT. The criterion is classified into five grades. 120 patients with a total of 141 lesions underwent whole-body bone scintigraphy and SPECT/CT. Two reviewers read the images according to the diagnostic criterion. With pathological diagnosis as the "gold standard", the diagnostic efficacy for bone metastases and the diagnostic agreement between the two reviewers were analyzed to validate the feasibility of the criterion. Diagnostic effectiveness was expressed in terms of sensitivity, specificity, positive predictive value, negative predictive value, and accuracy. RESULTS: The diagnostic accuracy of the two reviewers was 90.1% and 92.9% respectively, sensitivity was both 100%, specificity was 41.7% and 58.3%, positive predictive value was 89.3% and 92.1%, and negative predictive value was both 100%. The kappa value of the diagnostic tests performed by the two reviewers on whole-body bone scintigraphy combined with SPECT/CT was 0.919 (P < 0.001). CONCLUSION: The grading diagnostic criterion for bone metastases by whole-body bone scintigraphy combined with SPECT/CT has high diagnostic accuracy and good consistency between reviewers, but the specificity was still low even with SPECT/CT.


Sujet(s)
Tumeurs osseuses/imagerie diagnostique , Tumeurs osseuses/secondaire , Tomographie par émission monophotonique couplée à la tomodensitométrie , Imagerie du corps entier , Adulte , Femelle , Humains , Mâle , Adulte d'âge moyen , Valeur prédictive des tests , Études rétrospectives , Sensibilité et spécificité
13.
Biochem Biophys Res Commun ; 525(4): 823-829, 2020 05 14.
Article de Anglais | MEDLINE | ID: mdl-32164940

RÉSUMÉ

Barnacles are notorious marine fouling organisms. Their successful attachment to a substrate requires that they search for an appropriate habitat during their cyprid stage. A chemical cue called SIPC (Settlement-Inducing Protein Complex) has been shown to play a key role in the induction of cyprid gregarious settlement; however, the underlying biochemical mechanism remains unclear. Here, RNA-seq was used to examine the gene expression profiles of Amphibalanus amphitrite cyprids in response to SIPC and to identify SIPC-activated intracellular signaling pathways. A total of 389 unigenes were differentially expressed in response to SIPC, and cement protein genes were not among them. KEGG enrichment analysis suggested that SNARE interactions in the vesicular transport pathway were significantly influenced by SIPC treatment, indicating a possible role for SIPC in triggering protein transportation and secretion. Several genes with specific functions in metamorphosis were found among the differentially expressed genes (DEGs). GO (Gene Ontology) enrichment analysis revealed that the DEGs were significantly enriched in enamel mineralization pathways, suggesting that SIPC may also be involved in the activation of mineralization.


Sujet(s)
Thoracica/physiologie , Transcriptome , Animaux , Analyse de profil d'expression de gènes , Larve , Métamorphose biologique/génétique , Transport des protéines/génétique , Thoracica/génétique
14.
Langmuir ; 36(10): 2673-2682, 2020 03 17.
Article de Anglais | MEDLINE | ID: mdl-32097553

RÉSUMÉ

The reflectin proteins have been extensively studied for their role in reflectance in cephalopods. In the recently evolved Loliginid squids, these proteins and the structural color they regulate are dynamically tunable, enhancing their effectiveness for camouflage and communication. In these species, the reflectins are found in highest concentrations within the structurally tunable, membrane enclosed, periodically stacked lamellae of subcellular Bragg reflectors and in the intracellular vesicles of specialized skin cells known as iridocytes and leuocophores, respectively. To better understand the interactions between the reflectins and the membrane structures that encompass them, we analyzed the interactions of two purified reflectins with synthetic phospholipid membrane vesicles similar in composition to cellular membranes, using confocal fluorescence microscopy and dynamic light scattering. The purified recombinant reflectins were found to drive multivalent vesicle agglomeration in a ratio-dependent and saturable manner. Extensive proteolytic digestion terminated with PMSF of the reflectin A1-vesicle complexes triggered energetic membrane rearrangement, resulting in vesicle fusion, fission, and tubulation. This behavior contrasted markedly with that of vesicles complexed with reflectin C, from which PMSF-terminated proteolysis only released the original size vesicles. Clues to the basis for this difference, residing in significant differences between the structures of the two reflectins, led to the suggestion that specific reflectin-membrane interactions may play a role in the ontogenetic formation, long-term maintenance, and/or dynamic behavior of their biophotonically active host membrane nanostructures. Similar energetic remodeling has been associated with osmotic stress in other membrane systems, suggesting a path to reconstitution of the biophotonic system in vitro.


Sujet(s)
Phospholipides , Protéines , Animaux , Decapodiformes , Peau
15.
Int J Mol Sci ; 18(6)2017 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-28587227

RÉSUMÉ

The influence of temperature on plants is essential. However, our knowledge on the intricate regulation process underlying heat stress (HS) response in plants is limited. Recently, information about thermal sensors in vivo has begun to emerge. In this study, another primary environmental stimulus, light, was verified once again to work with temperature synergistically on plants, through the modulation of numerous biological processes. With the application of transcriptomic analysis, a substantial number of heat-responsive genes were detected involved in both light- and phytohormone-mediated pathways in Arabidopsis. During this process, phytoreceptor phyB acts as a molecular switch to turn on or turn off several other genes HS response, under different light conditions. Furthermore, a morphological study showed the afunction of phyB enhanced plants thermal tolerance, confirming the important role of this phytochrome in temperature perception and response in plants. This study adds data to the picture of light and temperature signaling cross-talk in plants, which is important for the exploration of complicated HS responses or light-mediated mechanisms. Furthermore, based on its influence on Arabidopsis thermal response in both morphological and physiological levels, phyB is a photoreceptor, as revealed before, as well as an essential thermal sensor in plants.


Sujet(s)
Arabidopsis/physiologie , Perception , Cellules photoréceptrices/métabolisme , Phytochrome B/génétique , Température , Thermotolérance/génétique , Biologie informatique , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes végétaux/effets des radiations , Gene Ontology , Génotype , Lumière , Phytochrome B/métabolisme , Stress physiologique/génétique , Transcriptome
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