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Fulltext Research on Cartilage 3D Printing Technology Based on SA-GA-HA

Chen Y, Gong Y, Shan L, Tan CY, Al-Furjan MS, Ramesh S, et al.

Materials (Basel), 2023 Jul 28;16(15).
PMID: 37570016 DOI: 10.3390/ma16155312

Cartilage damage is difficult to heal and poses a serious problem to human health as it can lead to osteoarthritis. In this work, we explore the application of biological 3D printing to manufacture new cartilage scaffolds to promote cartilage regeneration. The hydrogel made by mixing sodium alginate (SA) and gelatin (GA) has high biocompatibility, but its mechanical properties are poor. The addition of hydroxyapatite (HA) can enhance its mechanical properties. In this paper, the preparation scheme of the SA-GA-HA composite hydrogel cartilage scaffold was explored, the scaffolds prepared with different concentrations were compared, and better formulations were obtained for printing and testing. Mathematical modeling of the printing process of the bracket, simulation analysis of the printing process based on the mathematical model, and adjustment of actual printing parameters based on the results of the simulation were performed. The cartilage scaffold, which was printed using Bioplotter 3D printer, exhibited useful mechanical properties suitable for practical needs. In addition, ATDC-5 cells were seeded on the cartilage scaffolds and the cell survival rate was found to be higher after one week. The findings demonstrated that the fabricated chondrocyte scaffolds had better mechanical properties and biocompatibility, providing a new scaffold strategy for cartilage tissue regeneration.
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1

Klionsky DJ, Abdel-Aziz AK, Abdelfatah S, Abdellatif M, Abdoli A, Abel S, et al.

Autophagy, 2021 Jan;17(1):1-382.
PMID: 33634751 DOI: 10.1080/15548627.2020.1797280

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
Fulltext Comparative transcriptomics sheds light on differential adaptation and species diversification between two Melastoma species and their F1 hybrid

Ng WL, Wu W, Zou P, Zhou R

AoB Plants, 2019 Apr;11(2):plz019.
PMID: 31037213 DOI: 10.1093/aobpla/plz019

Variation in gene expression has been shown to promote adaptive divergence, and can lead to speciation. The plant genus Melastoma, thought to have diversified through adaptive radiation, provides an excellent model for the study of gene expressional changes during adaptive differentiation and following interspecific hybridization. In this study, we performed RNA-seq on M. candidum, M. sanguineum and their F1 hybrid, to investigate the role of gene expression in species diversification within the genus. Reference transcriptomes were assembled using combined data from both parental species, resulting in 50 519 and 48 120 transcripts for the leaf and flower petal, after removing redundancy. Differential expression analysis uncovered 3793 and 2116 differentially expressed (DE) transcripts, most of which are between M. candidum and M. sanguineum. Differential expression was observed for genes related to light responses, as well as genes that regulate the development of leaf trichomes, a trait that among others is thought to protect plants against sunlight, suggesting the differential adaptation of the species to sunlight intensity. The analysis of positively selected genes between the two species also revealed possible differential adaptation to other abiotic stresses such as drought and temperature. In the hybrid, almost all possible modes of expression were observed at the DE transcripts, although at most transcripts, the expression levels were similar to that of either parent instead of being intermediate. A small number of transgressively expressed transcripts that matched genes known to promote plant growth and adaptation to stresses in new environments were also found, possibly explaining the vigour observed in the hybrid. The findings in this study provided insights into the role of gene expression in the diversification of Melastoma, which we believe is an important example for more cross-taxa comparisons in the future.
Fulltext Molecular identification of natural hybridization between Melastoma malabathricum and Melastoama beccarianum in Sarawak, Malaysia

Wu R, Zou P, Tan G, Hu Z, Wang Y, Ning Z, et al.

Ecol Evol, 2019 May;9(10):5766-5776.
PMID: 31160997 DOI: 10.1002/ece3.5160

Hybridization is very common in flowering plants and it plays a significant role in plant evolution and adaptation. Melastoma L. (Melastomataceae) comprises about 80-90 species in tropical Asia and Oceania, among which 41 species occur in Borneo. Natural hybridization is frequently reported in Melastoma in China, but so far there have been no confirmed cases of hybridization in Southeast Asia (including Borneo), where most species occur. Here, we identified a case of natural hybridization between Melastoma malabathricum L. and Melastoma beccarianum Cogn. in Sarawak, Malaysia, by using sequence data of three nuclear genes and one chloroplast intergenic spacer. Melastoma malabathricum is the most widespread species of this genus, occurring in almost the whole range of this genus, while M. beccarianum is a local species endemic to northern Borneo. Our results showed that natural hybridization and introgression occur between M. malabathricum and M. beccarianum, and the introgression was asymmetrical, mainly from M. malabathricum to M. beccarianum. As adaptive traits can be transferred by introgression, our study suggests that natural hybridization should be a significant mechanism for the evolution and adaptation of Melastoma in Southeast Asia. However, introgression from the common species M. malabathricum to the relatively rare species M. beccarianum may cause the decline of M. beccarianum, incurring conservation concern. With a large number of species of Melastoma and almost year-around flowering in Southeast Asia, more cases of natural hybridization are expected to be found and identified in near future.
Fulltext Effects of Pleistocene sea-level fluctuations on mangrove population dynamics: a lesson from Sonneratia alba

Yang Y, Li J, Yang S, Li X, Fang L, Zhong C, et al.

BMC Evol. Biol., 2017 01 18;17(1):22.
PMID: 28100168 DOI: 10.1186/s12862-016-0849-z

BACKGROUND: A large-scale systematical investigation of the influence of Pleistocene climate oscillation on mangrove population dynamics could enrich our knowledge about the evolutionary history during times of historical climate change, which in turn may provide important information for their conservation.
RESULTS: In this study, phylogeography of a mangrove tree Sonneratia alba was studied by sequencing three chloroplast fragments and seven nuclear genes. A low level of genetic diversity at the population level was detected across its range, especially at the range margins, which was mainly attributed to the steep sea-level drop and associated climate fluctuations during the Pleistocene glacial periods. Extremely small effective population size (Ne) was inferred in populations from both eastern and western Malay Peninsula (44 and 396, respectively), mirroring the fragility of mangrove plants and their paucity of robustness against future climate perturbations and human activity. Two major genetic lineages of high divergence were identified in the two mangrove biodiversity centres: the Indo-Malesia and Australasia regions. The estimated splitting time between these two lineages was 3.153 million year ago (MYA), suggesting a role for pre-Pleistocene events in shaping the major diversity patterns of mangrove species. Within the Indo-Malesia region, a subdivision was implicated between the South China Sea (SCS) and the remaining area with a divergence time of 1.874 MYA, corresponding to glacial vicariance when the emerged Sunda Shelf halted genetic exchange between the western and eastern coasts of the Malay Peninsula during Pleistocene sea-level drops. Notably, genetic admixture was observed in populations at the boundary regions, especially in the two populations near the Malacca Strait, indicating secondary contact between divergent lineages during interglacial periods. These interregional genetic exchanges provided ample opportunity for the re-use of standing genetic variation, which could facilitate mangrove establishment and adaptation in new habitats, especially in the context of global climate changes.
CONCLUSION: Phylogeogrpahic analysis in this study reveal that Pleistocene sea-level fluctuations had profound influence on population differentiation of the mangrove tree S. alba. Our study highlights the fragility of mangrove plants and offers a guide for the conservation of coastal mangrove communities experiencing ongoing changes in sea-level.
Collagens for surimi gel fortification: Type-dependent effects and the difference between type I and type II

Zhao Y, Lu K, Piao X, Song Y, Wang L, Zhou R, et al.

Food Chem, 2023 May 01;407:135157.
PMID: 36529012 DOI: 10.1016/j.foodchem.2022.135157

Surimi products have unsatisfactory gel properties. Hence, this study evaluates the effect of collagen-adding on surimi gel properties and provides the first observation results regarding collagen type influence. With higher water solubility and more charged amino acids than type II, collagen type I intertwines with surimi myofibrillar proteins better to induce higher exposure of protein functional domains, more sufficient conformational changes of myosin and greater formation of chemical forces among proteins. These enhancements accelerate the gelation rate, leading to a well-stabilized surimi gel. The collagen I-containing surimi gels show more compact structures with uniformly distributed smaller pores than those containing collagen II, thereby providing the final products with higher water holding capacity and better textural profiles. As such, the surimi gel fortification performance of collagen I and the well-elucidated collagen-myofibrillar protein interaction mechanism will guide the further exploitation of collagen as an effective additive in the food industry.
Fulltext Analyses of Plastome Sequences Improve Phylogenetic Resolution and Provide New Insight Into the Evolutionary History of Asian Sonerileae/Dissochaeteae

Zhou Q, Lin CW, Ng WL, Dai J, Denda T, Zhou R, et al.

Front Plant Sci, 2019;10:1477.
PMID: 31824528 DOI: 10.3389/fpls.2019.01477

Sonerileae/Dissochaeteae (Melastomataceae) comprises ca. 50 genera, two thirds of which occur in Southeast Asia. Phylogenetic relationships within this clade remain largely unclear, which hampers our understanding of its origin, evolution, and biogeography. Here, we explored the use of chloroplast genomes in phylogenetic reconstruction of Sonerileae/Dissochaeteae, by sampling 138 species and 23 genera in this clade. A total of 151 complete plastid genomes were assembled for this study. Plastid genomic data provided better support for the backbone of the Sonerileae/Dissochaeteae phylogeny, and also for relationships among most closely related species, but failed to resolve the short internodes likely resulted from rapid radiation. Trees inferred from plastid genome and nrITS sequences were largely congruent regarding the major lineages of Sonerileae/Dissochaeteae. The present analyses recovered 15 major lineages well recognized in both nrITS and plastid phylogeny. Molecular dating and biogeographical analyses indicated a South American origin for Sonerileae/Dissochaeteae during late Eocene (stem age: 34.78 Mya). Two dispersal events from South America to the Old World were detected in late Eocene (33.96 Mya) and Mid Oligocene (28.33 Mya) respectively. The core Asian clade began to diversify around early Miocene in Indo-Burma and dispersed subsequently to Malesia and Sino-Japanese regions, possibly promoted by global temperature changes and East Asian monsoon activity. Our analyses supported previous hypothesis that Medinilla reached Madagascar by transoceanic dispersal in Miocene. In addition, generic limits of some genera concerned were discussed.
Fulltext The Impact of Social Media on Employee Mental Health and Behavior Based on the Context of Intelligence-Driven Digital Data

Zhou R, Luo Z, Zhong S, Zhang X, Liu Y

Int J Environ Res Public Health, 2022 Dec 17;19(24).
PMID: 36554845 DOI: 10.3390/ijerph192416965

With the rapid development and widespread popularity of the Internet, employee social media use at work has become an increasingly common phenomenon in organizations. This paper analyzes 105 related papers from the Social Science Citation Index in Web of Science through Scoping Review to clarify the definition and characteristics of employee social media use and the types of social media and summarizes the current research methods. Then, the reasons for employees' willingness and refusal to use social media and the positive and negative effects of employee social media use on employees' work attitudes, behaviors, and performance are discussed. Then, the mediating variables, moderating variables, and theoretical frameworks used in the relevant studies are described, and a comprehensive model of employee social media use is constructed. Finally, this paper indicates future research directions based on the latest research results in 2020-2022, i.e., improving research methods, increasing antecedent studies, expanding consequence research, and expanding mediating variables, moderating variables, and theoretical perspectives.
Fulltext A Study on the Influencing Factors of Consumers' Purchase Intention During Livestreaming e-Commerce: The Mediating Effect of Emotion

Zhou R, Tong L

Front Psychol, 2022;13:903023.
PMID: 35615168 DOI: 10.3389/fpsyg.2022.903023

With the deep popularity of mobile Internet, the "eyeball economy" is more active than ever. Driven by powerful modern media, livestreaming, as a new form of attracting public attention to obtain economic benefits, is worth studying its influence path on consumers. Based on the technology acceptance model and the mediating effect of emotion, this study constructs the consumer influencing factor model of livestreaming e-commerce. The research model and related hypotheses are verified by SPSS and linear multiple regression models. The research found that emotional trust and perceived emotional value could be regarded as mediating variables to stimulate consumers' purchase intention in livestreaming e-commerce. They have a full mediating effect on product and atmosphere and a partial mediating effect on homogeneity and promotion, which identifies that online celebrity's homogeneity, and sales promotion could influence consumers' purchase intention through the partial mediating role of emotional trust and perceived emotional value, while product and atmosphere induced by emotional contagion could exert influence on consumers' purchase intention through the full mediating effect of emotional trust and perceived emotional value.