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Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, et al.

Autophagy, 2016;12(1):1-222.
PMID: 26799652 DOI: 10.1080/15548627.2015.1100356
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 Identification of common genetic risk variants for autism spectrum disorder

Grove J, Ripke S, Als TD, Mattheisen M, Walters RK, Won H, et al.

Nat Genet, 2019 03;51(3):431-444.
PMID: 30804558 DOI: 10.1038/s41588-019-0344-8

Autism spectrum disorder (ASD) is a highly heritable and heterogeneous group of neurodevelopmental phenotypes diagnosed in more than 1% of children. Common genetic variants contribute substantially to ASD susceptibility, but to date no individual variants have been robustly associated with ASD. With a marked sample-size increase from a unique Danish population resource, we report a genome-wide association meta-analysis of 18,381 individuals with ASD and 27,969 controls that identified five genome-wide-significant loci. Leveraging GWAS results from three phenotypes with significantly overlapping genetic architectures (schizophrenia, major depression, and educational attainment), we identified seven additional loci shared with other traits at equally strict significance levels. Dissecting the polygenic architecture, we found both quantitative and qualitative polygenic heterogeneity across ASD subtypes. These results highlight biological insights, particularly relating to neuronal function and corticogenesis, and establish that GWAS performed at scale will be much more productive in the near term in ASD.
Fulltext Drivers and mechanisms of tree mortality in moist tropical forests

McDowell N, Allen CD, Anderson-Teixeira K, Brando P, Brienen R, Chambers J, et al.

New Phytol, 2018 08;219(3):851-869.
PMID: 29451313 DOI: 10.1111/nph.15027

Tree mortality rates appear to be increasing in moist tropical forests (MTFs) with significant carbon cycle consequences. Here, we review the state of knowledge regarding MTF tree mortality, create a conceptual framework with testable hypotheses regarding the drivers, mechanisms and interactions that may underlie increasing MTF mortality rates, and identify the next steps for improved understanding and reduced prediction. Increasing mortality rates are associated with rising temperature and vapor pressure deficit, liana abundance, drought, wind events, fire and, possibly, CO2 fertilization-induced increases in stand thinning or acceleration of trees reaching larger, more vulnerable heights. The majority of these mortality drivers may kill trees in part through carbon starvation and hydraulic failure. The relative importance of each driver is unknown. High species diversity may buffer MTFs against large-scale mortality events, but recent and expected trends in mortality drivers give reason for concern regarding increasing mortality within MTFs. Models of tropical tree mortality are advancing the representation of hydraulics, carbon and demography, but require more empirical knowledge regarding the most common drivers and their subsequent mechanisms. We outline critical datasets and model developments required to test hypotheses regarding the underlying causes of increasing MTF mortality rates, and improve prediction of future mortality under climate change.
Fulltext Rapid Targeted Next-Generation Sequencing Platform for Molecular Screening and Clinical Genotyping in Subjects with Hemoglobinopathies

Shang X, Peng Z, Ye Y, Asan, Zhang X, Chen Y, et al.

EBioMedicine, 2017 Sep;23:150-159.
PMID: 28865746 DOI: 10.1016/j.ebiom.2017.08.015

Hemoglobinopathies are among the most common autosomal-recessive disorders worldwide. A comprehensive next-generation sequencing (NGS) test would greatly facilitate screening and diagnosis of these disorders. An NGS panel targeting the coding regions of hemoglobin genes and four modifier genes was designed. We validated the assay by using 2522 subjects affected with hemoglobinopathies and applied it to carrier testing in a cohort of 10,111 couples who were also screened through traditional methods. In the clinical genotyping analysis of 1182 β-thalassemia subjects, we identified a group of additional variants that can be used for accurate diagnosis. In the molecular screening analysis of the 10,111 couples, we detected 4180 individuals in total who carried 4840 mutant alleles, and identified 186 couples at risk of having affected offspring. 12.1% of the pathogenic or likely pathogenic variants identified by our NGS assay, which were undetectable by traditional methods. Compared with the traditional methods, our assay identified an additional at-risk 35 couples. We describe a comprehensive NGS-based test that offers advantages over the traditional screening/molecular testing methods. To our knowledge, this is among the first large-scale population study to systematically evaluate the application of an NGS technique in carrier screening and molecular diagnosis of hemoglobinopathies.
Fulltext The draft genomes of five agriculturally important African orphan crops

Chang Y, Liu H, Liu M, Liao X, Sahu SK, Fu Y, et al.

Gigascience, 2019 03 01;8(3).
PMID: 30535374 DOI: 10.1093/gigascience/giy152

BACKGROUND: The expanding world population is expected to double the worldwide demand for food by 2050. Eighty-eight percent of countries currently face a serious burden of malnutrition, especially in Africa and south and southeast Asia. About 95% of the food energy needs of humans are fulfilled by just 30 species, of which wheat, maize, and rice provide the majority of calories. Therefore, to diversify and stabilize the global food supply, enhance agricultural productivity, and tackle malnutrition, greater use of neglected or underutilized local plants (so-called orphan crops, but also including a few plants of special significance to agriculture, agroforestry, and nutrition) could be a partial solution.
RESULTS: Here, we present draft genome information for five agriculturally, biologically, medicinally, and economically important underutilized plants native to Africa: Vigna subterranea, Lablab purpureus, Faidherbia albida, Sclerocarya birrea, and Moringa oleifera. Assembled genomes range in size from 217 to 654 Mb. In V. subterranea, L. purpureus, F. albida, S. birrea, and M. oleifera, we have predicted 31,707, 20,946, 28,979, 18,937, and 18,451 protein-coding genes, respectively. By further analyzing the expansion and contraction of selected gene families, we have characterized root nodule symbiosis genes, transcription factors, and starch biosynthesis-related genes in these genomes.
CONCLUSIONS: These genome data will be useful to identify and characterize agronomically important genes and understand their modes of action, enabling genomics-based, evolutionary studies, and breeding strategies to design faster, more focused, and predictable crop improvement programs.
Fulltext Nursing students' and faculty members' experiences of online education during COVID-19 across Southeast Asia: A Photovoice study

Kunaviktikul W, Ang E, Baridwan NS, Bernal AB, Dones LBP, Flores JL, et al.

Nurse Educ Today, 2022 Apr;111:105307.
PMID: 35217457 DOI: 10.1016/j.nedt.2022.105307

BACKGROUND: The COVID-19 pandemic has caused extraordinary disruptions to education systems globally, forcing a rapid switch from conventional to online education. Although some qualitative studies have been carried out exploring the online education experiences of nursing students and faculty members during the COVID-19 pandemic, to our knowledge, no study has used the Photovoice approach.
OBJECTIVES: To explore the experiences of nursing students and faculty members as related to online education during the COVID-19 pandemic.
DESIGN: A descriptive qualitative design using Photovoice was adopted.
SETTING: The study took place across five countries and one city in Southeast Asia (Indonesia, Malaysia, the Philippines, Thailand, Vietnam, and Hong Kong).
PARTICIPANTS: Fifty-two nursing students and twenty-eight nursing faculty members who participated in online education during the COVID-19 pandemic.
METHODS: Each participant submitted one photo substantiated with written reflections. Data were analysed using thematic analysis. Ethical approval was obtained from institution-specific ethics boards.
RESULTS: Three themes and eleven sub-themes emerged from the data. The three main themes were: 1) Psychological roadblocks to online education; 2) Developing resilience despite adversities; and 3) Online education: What worked and what did not.
CONCLUSION: Through Photovoice, the reflections revealed that nursing students and faculty members were generally overwhelmed with the online education experience. At the same time, participants were satisfied with the flexibility and convenience, opportunities for professional and personal development and safety afforded by online education. However, concerns over academic integrity, practical skills and clinical competencies, engagement and participation, the duality of technology and social isolation out-shadowed the advantages. It is worthwhile to explore the concerns raised to enhance online education across the nursing curriculum.
Fulltext Salutogenesis and COVID-19 pandemic impacting nursing education across SEANERN affiliated universities: A multi-national study

Shorey S, Ang E, Baridwan NS, Bonito SR, Dones LBP, Flores JLA, et al.

Nurse Educ Today, 2022 Mar;110:105277.
PMID: 35101809 DOI: 10.1016/j.nedt.2022.105277

BACKGROUND: The COVID-19 pandemic has disrupted the lives of many. Particularly, nursing students experience greater stress as their normal curriculum is interrupted and some of them face the risk of being infected as frontline workers. Nursing faculty members may face similar struggles, in addition to developing teaching materials for online learning. Thus, it is important to examine the faculty members' and students' views on their ability to adapt during the pandemic to obtain a holistic view of how learning and training has been affected.
DESIGN: The descriptive cross-sectional quantitative design was used.
SETTINGS: Data were collected from Southeast and East Asian Nursing Education and Research Network (SEANERN) affiliated nursing institutions from January 2021 to August 2021.
PARTICIPANTS: A total of 1897 nursing students and 395 faculty members from SEANERN-affiliated nursing institutions in Cambodia, Hong Kong, Indonesia, Japan, Laos, Malaysia, Philippines, Singapore, Thailand and Vietnam were recruited for this study.
METHODS: Quantitative surveys were used to explore the satisfaction levels in education modalities, confidence levels, psychosocial well-being, sense of coherence and stress levels of nursing students and faculty members during the COVID-19 pandemic.
RESULTS: Participants were mostly satisfied with the new education modalities, although most students felt that their education was compromised. Both groups showed positive levels of psychosocial well-being, despite scoring low to medium on the sense of coherence scale and experiencing great stress. The participants' sense of coherence was positively correlated with their psychosocial well-being and negatively correlated with stress levels.
CONCLUSIONS: While the COVID-19 pandemic had negatively impacted the lives of nursing students and faculty members, most of them had a healthy level of psychosocial well-being. Having a strong sense of coherence was associated with better psychosocial health and lower stress levels. As such, it may be helpful to develop interventions aimed at improving the sense of coherence of nursing students and staff to help them manage stressors better.
Ancient DNA reveals genetic admixture in China during tiger evolution

Sun X, Liu YC, Tiunov MP, Gimranov DO, Zhuang Y, Han Y, et al.

Nat Ecol Evol, 2023 Nov;7(11):1914-1929.
PMID: 37652999 DOI: 10.1038/s41559-023-02185-8

The tiger (Panthera tigris) is a charismatic megafauna species that originated and diversified in Asia and probably experienced population contraction and expansion during the Pleistocene, resulting in low genetic diversity of modern tigers. However, little is known about patterns of genomic diversity in ancient populations. Here we generated whole-genome sequences from ancient or historical (100-10,000 yr old) specimens collected across mainland Asia, including a 10,600-yr-old Russian Far East specimen (RUSA21, 8× coverage) plus six ancient mitogenomes, 14 South China tigers (0.1-12×) and three Caspian tigers (4-8×). Admixture analysis showed that RUSA21 clustered within modern Northeast Asian phylogroups and partially derived from an extinct Late Pleistocene lineage. While some of the 8,000-10,000-yr-old Russian Far East mitogenomes are basal to all tigers, one 2,000-yr-old specimen resembles present Amur tigers. Phylogenomic analyses suggested that the Caspian tiger probably dispersed from an ancestral Northeast Asian population and experienced gene flow from southern Bengal tigers. Lastly, genome-wide monophyly supported the South China tiger as a distinct subspecies, albeit with mitochondrial paraphyly, hence resolving its longstanding taxonomic controversy. The distribution of mitochondrial haplogroups corroborated by biogeographical modelling suggested that Southwest China was a Late Pleistocene refugium for a relic basal lineage. As suitable habitat returned, admixture between divergent lineages of South China tigers took place in Eastern China, promoting the evolution of other northern subspecies. Altogether, our analysis of ancient genomes sheds light on the evolutionary history of tigers and supports the existence of nine modern subspecies.
Fulltext Mental Health among Adults during the COVID-19 Pandemic Lockdown: A Cross-Sectional Multi-Country Comparison

Ding K, Yang J, Chin MK, Sullivan L, Demirhan G, Violant-Holz V, et al.

Int J Environ Res Public Health, 2021 03 07;18(5).
PMID: 33800008 DOI: 10.3390/ijerph18052686

Despite the global impact of COVID-19, studies comparing the effects of COVID-19 on population mental health across countries are sparse. This study aimed to compare anxiety and depression symptoms during the COVID-19 lockdown among adults from 11 countries and to examine their associations with country-level COVID-19 factors and personal COVID-19 exposure. A cross-sectional survey was conducted among adults (≥18 years) in 11 countries (Brazil, Bulgaria, China, India, Ireland, North Macedonia, Malaysia, Singapore, Spain, Turkey, United States). Mental health (anxiety, depression, resilient coping, hope) and other study data were collected between June-August 2020. Of the 13,263 participants, 62.8% were female and 51.7% were 18-34 years old. Participants living in Brazil had the highest anxiety and depression symptoms while participants living in Singapore had the lowest. Greater personal COVID-19 exposure was associated with increased anxiety and depression symptoms, but country-level COVID-19 factors were not. Higher levels of hope were associated with reduced anxiety and depression; higher levels of resilient coping were associated with reduced anxiety but not depression. Substantial variations exist in anxiety and depression symptoms across countries during the COVID-19 lockdown, with personal COVID-19 exposure being a significant risk factor. Strategies that mitigate COVID-19 exposure and enhance hope and resilience may reduce anxiety and depression during global emergencies.
Fulltext Physical Activity among Adults Residing in 11 Countries during the COVID-19 Pandemic Lockdown

Ding K, Yang J, Chin MK, Sullivan L, Durstine JL, Violant-Holz V, et al.

Int J Environ Res Public Health, 2021 Jul 01;18(13).
PMID: 34280992 DOI: 10.3390/ijerph18137056

During the novel coronavirus (COVID-19) pandemic, physical activity (PA) behaviors were altered worldwide due to public health measures such as "lockdown." This study described PA among adults residing in 11 countries during COVID-19 lockdown and examined factors associated with PA engagement. We conducted a cross-sectional anonymous survey among adults (≥18 years old) in 11 countries (Brazil, Bulgaria, China, India, Ireland, Malaysia, North Macedonia, Singapore, Spain, Turkey, United States). Of 11,775 participants, 63.7% were female and 52.8% were 18-34 years old. More than 40% of participants were insufficiently active (43.9%) and reported a decrease in their PA during lockdown (44.8%). Statistically significant differences were observed in (1) proportions of participants being insufficiently active, (2) level of PA, and (3) decrease in PA across the 11 countries. More stringent governmental policy responses were associated with greater likelihood of being insufficiently active during lockdown (adjusted odds ratio = 1.22, 95% confidence interval = 1.03, 1.45). Higher depression or anxiety scores were associated with greater likelihood of decreased level of PA during lockdown.We found substantial reductions in PA levels during COVID-19 lockdown across countries. Country-specific PA promotion interventions are needed during this and similar global emergencies.
Fulltext Human cytomegalovirus may promote tumour progression by upregulating arginase-2

Costa H, Xu X, Overbeek G, Vasaikar S, Patro CP, Kostopoulou ON, et al.

Oncotarget, 2016 Jul 26;7(30):47221-47231.
PMID: 27363017 DOI: 10.18632/oncotarget.9722

BACKGROUND: Both arginase (ARG2) and human cytomegalovirus (HCMV) have been implicated in tumorigenesis. However, the role of ARG2 in the pathogenesis of glioblastoma (GBM) and the HCMV effects on ARG2 are unknown. We hypothesize that HCMV may contribute to tumorigenesis by increasing ARG2 expression.
RESULTS: ARG2 promotes tumorigenesis by increasing cellular proliferation, migration, invasion and vasculogenic mimicry in GBM cells, at least in part due to overexpression of MMP2/9. The nor-NOHA significantly reduced migration and tube formation of ARG2-overexpressing cells. HCMV immediate-early proteins (IE1/2) or its downstream pathways upregulated the expression of ARG2 in U-251 MG cells. Immunostaining of GBM tissue sections confirmed the overexpression of ARG2, consistent with data from subsets of Gene Expression Omnibus. Moreover, higher levels of ARG2 expression tended to be associated with poorer survival in GBM patient by analyzing data from TCGA.
METHODS: The role of ARG2 in tumorigenesis was examined by proliferation-, migration-, invasion-, wound healing- and tube formation assays using an ARG2-overexpressing cell line and ARG inhibitor, N (omega)-hydroxy-nor-L-arginine (nor-NOHA) and siRNA against ARG2 coupled with functional assays measuring MMP2/9 activity, VEGF levels and nitric oxide synthase activity. Association between HCMV and ARG2 were examined in vitro with 3 different GBM cell lines, and ex vivo with immunostaining on GBM tissue sections. The viral mechanism mediating ARG2 induction was examined by siRNA approach. Correlation between ARG2 expression and patient survival was extrapolated from bioinformatics analysis on data from The Cancer Genome Atlas (TCGA).
CONCLUSIONS: ARG2 promotes tumorigenesis, and HCMV may contribute to GBM pathogenesis by upregulating ARG2.
Fulltext Extant primitively segmented spiders have recently diversified from an ancient lineage

Xu X, Liu F, Cheng RC, Chen J, Xu X, Zhang Z, et al.

Proc Biol Sci, 2015 Jun 07;282(1808):20142486.
PMID: 25948684 DOI: 10.1098/rspb.2014.2486

Living fossils are lineages that have retained plesiomorphic traits through long time periods. It is expected that such lineages have both originated and diversified long ago. Such expectations have recently been challenged in some textbook examples of living fossils, notably in extant cycads and coelacanths. Using a phylogenetic approach, we tested the patterns of the origin and diversification of liphistiid spiders, a clade of spiders considered to be living fossils due to their retention of arachnid plesiomorphies and their exclusive grouping in Mesothelae, an ancient clade sister to all modern spiders. Facilitated by original sampling throughout their Asian range, we here provide the phylogenetic framework necessary for reconstructing liphistiid biogeographic history. All phylogenetic analyses support the monophyly of Liphistiidae and of eight genera. As the fossil evidence supports a Carboniferous Euramerican origin of Mesothelae, our dating analyses postulate a long eastward over-land dispersal towards the Asian origin of Liphistiidae during the Palaeogene (39-58 Ma). Contrary to expectations, diversification within extant liphistiid genera is relatively recent, in the Neogene and Late Palaeogene (4-24 Ma). While no over-water dispersal events are needed to explain their evolutionary history, the history of liphistiid spiders has the potential to play prominently in vicariant biogeographic studies.
Fulltext Genomic evidence for the Chinese mountain cat as a wildcat conspecific (Felis silvestris bieti) and its introgression to domestic cats

Yu H, Xing YT, Meng H, He B, Li WJ, Qi XZ, et al.

Sci Adv, 2021 Jun;7(26).
PMID: 34162544 DOI: 10.1126/sciadv.abg0221

The Qinghai-Tibet Plateau endemic Chinese mountain cat has a controversial taxonomic status, whether it is a true species or a wildcat (Felis silvestris) subspecies and whether it has contributed to cat (F. s. catus) domestication in East Asia. Here, we sampled F. silvestris lineages across China and sequenced 51 nuclear genomes, 55 mitogenomes, and multilocus regions from 270 modern or museum specimens. Genome-wide analyses classified the Chinese mountain cat as a wildcat conspecific F. s. bieti, which was not involved in cat domestication of China, thus supporting a single domestication origin arising from the African wildcat (F. s. lybica). A complex hybridization scenario including ancient introgression from the Asiatic wildcat (F. s. ornata) to F. s. bieti, and contemporary gene flow between F. s. bieti and sympatric domestic cats that are likely recent Plateau arrivals, raises the prospect of disrupted wildcat genetic integrity, an issue with profound conservation implications.
Educational environments in Asian medical schools: A cross-national comparison between Malaysia, Singapore, and China

Arokiamary B, Russell V, Lim HA, Koay JM, Xia J, Zhao XH, et al.

Asia Pac Psychiatry, 2021 Jun;13(2):e12454.
PMID: 33646626 DOI: 10.1111/appy.12454

INTRODUCTION: Perceptions of the educational environment (EE) represent an important source of information on medical students' learning experience. Understanding and addressing these perceptions can help inform initiatives designed to improve the learning experience and educational outcomes, while comparison of student perceptions across medical schools can provide an added perspective. The aim of the study was to compare the EEs of three Asian medical schools: Royal College of Surgeons in Ireland and University College Dublin Malaysia Campus, Yong Loo Lin School of Medicine, Singapore and Xiangya School of Medicine, China.
METHODS: Medical students in the clinical years (N = 1063) participated in a cross-sectional study using the Dundee Ready Educational Environment Measure (DREEM). Data were analyzed using SPSS version 22.
RESULTS: There were significant differences between the three medical schools in the total DREEM scores (F [2, 1059] = 38.29, p
Phylogenomic Analysis of Ultraconserved Elements Resolves the Evolutionary and Biogeographic History of Segmented Trapdoor Spiders

Xu X, Su YC, Ho SYW, Kuntner M, Ono H, Liu F, et al.

Syst Biol, 2021 Oct 13;70(6):1110-1122.
PMID: 33367903 DOI: 10.1093/sysbio/syaa098

The segmented trapdoor spiders (Liphistiidae) are the sole surviving family of the suborder Mesothelae, which forms the sister lineage to all other living spiders. Liphistiids have retained a number of plesiomorphic traits and their present-day distribution is limited to East and Southeast Asia. Studying this group has the potential to shed light on the deep evolutionary history of spiders, but the phylogeny and divergence times of the family have not been resolved with confidence. We performed phylogenomic and molecular dating analyses of 2765 ultraconserved element loci from 185 liphistiid taxa. Our analyses show that the crown group of Liphistiidae appeared in the mid-Cretaceous at 102 Ma (95% credibility interval 92-113 Ma), but it was not until the Neogene that much of the diversification within the family occurred in mainland Southeast and East Asia. This diversification was coincident with tectonic events such as the extension of the East Asian continental margin, as well as geological upheavals in Indochina induced by the collision between India and Asia. Our study highlights the important role of major tectonic events in shaping the evolutionary history, present-day diversity, and geographical distribution of mesothele and liphistiid spiders. [biogeography; concatenation; Liphistiidae; molecular dating; summary coalescent; UCEs.].
Fulltext A comparison of 25 complete chloroplast genomes between sister mangrove species Kandelia obovata and Kandelia candel geographically separated by the South China Sea

Xu X, Shen Y, Zhang Y, Li Q, Wang W, Chen L, et al.

Front Plant Sci, 2022;13:1075353.
PMID: 36684775 DOI: 10.3389/fpls.2022.1075353

In 2003, Kandelia obovata was identified as a new mangrove species differentiated from Kandelia candel. However, little is known about their chloroplast (cp) genome differences and their possible ecological significance. In this study, 25 whole cp genomes, with seven samples of K. candel from Malaysia, Thailand, and Bangladesh and 18 samples of K. obovata from China, were sequenced for comparison. The cp genomes of both species encoded 128 genes, namely 83 protein-coding genes, 37 tRNA genes, and eight rRNA genes, but the cp genome size of K. obovata was ~2 kb larger than that of K. candle due to the presence of more and longer repeat sequences. Of these, tandem repeats and simple sequence repeats exhibited great differences. Principal component analysis based on indels, and phylogenetic tree analyses constructed with homologous protein genes from the single-copy genes, as well as 38 homologous pair genes among 13 mangrove species, gave strong support to the separation of the two species within the Kandelia genus. Homologous genes ndhD and atpA showed intraspecific consistency and interspecific differences. Molecular dynamics simulations of their corresponding proteins, NAD(P)H dehydrogenase chain 4 (NDH-D) and ATP synthase subunit alpha (ATP-A), predicted them to be significantly different in the functions of photosynthetic electron transport and ATP generation in the two species. These results suggest that the energy requirement was a pivotal factor in their adaptation to differential environments geographically separated by the South China Sea. Our results also provide clues for future research on their physiological and molecular adaptation mechanisms to light and temperature.
Physicochemical stability, antioxidant activity, and antimicrobial activity of quercetin-loaded zein nanoparticles coated with dextrin-modified anionic polysaccharides

Zhang Z, Hu Y, Ji H, Lin Q, Li X, Sang S, et al.

Food Chem, 2023 Jul 30;415:135736.
PMID: 36863232 DOI: 10.1016/j.foodchem.2023.135736

Core-shell biopolymer nanoparticles are assembled from a hydrophobic protein (zein) core and a hydrophilic polysaccharide (carboxymethyl dextrin) shell. The nanoparticles were shown to have good stability and the ability to protect quercetin from chemical degradation under long-term storage, pasteurization, and UV irradiation. Spectroscopy analysis shows that electrostatic, hydrogen bonding, and hydrophobic interactions are the main driving forces for the formation of composite nanoparticles. Quercetin coated with nanoparticles significantly enhanced its antioxidant and antibacterial activities and showed good stability and slow release in vitro during simulated gastrointestinal digestion. Furthermore, the encapsulation efficiency of carboxymethyl dextrin-coated zein nanoparticles (81.2%) for quercetin was significantly improved compared with that of zein nanoparticles alone (58.4%). These results indicate that carboxymethyl dextrin-coated zein nanoparticles can significantly improve the bioavailability of hydrophobic nutrient molecules such as quercetin and provide a valuable reference for their application in the field of biological delivery of energy drinks and food.
High-Performance Diamond Phototransistor with Gate Controllable Gain and Speed

Ge L, Li B, Li G, Wang X, Cheong KY, Peng Y, et al.

J Phys Chem Lett, 2023 Jan 19;14(2):592-597.
PMID: 36633457 DOI: 10.1021/acs.jpclett.2c03637

This paper presents a fabricated solar-blind phototransistor based on hydrogen-terminated diamond. The phototransistor shows a large photocurrent and enhancement of responsivity over conventional two-terminal diamond-based photodetector. These enhancement effects are owing to the internal gain of the phototransistor. The fabricated phototransistor exhibits a high photoresponsivity (R) of 2.16 × 104 A/W and a detectivity (D*) of 9.63 × 1011 jones, with gate voltage (VG) and drain voltage of approximately -1.5 V and -5 V, respectively, under 213 nm light illumination. Even at ultralow operating voltage of -0.01 V, the device records satisfactory performance with R and D* of 146.7 A/W and 6.19 × 1010 jones, respectively. By adjusting the VG, photocurrent generation in the device can be continuously tuned from the fast photoconductive effect to the optical gating effect with high optical gain. When VG increases from 1.4 to 2.4 V, the decay time decreases from 1512.0 to 25.5 ms. Therefore, responsivity, dark current, Iphoto/Idark, and decay time of the device can be well tuned by VG.
Fulltext Mesenchymal stem cell-derived extracellular vesicles for immunomodulation and regeneration: a next generation therapeutic tool?

Kou M, Huang L, Yang J, Chiang Z, Chen S, Liu J, et al.

Cell Death Dis, 2022 Jul 04;13(7):580.
PMID: 35787632 DOI: 10.1038/s41419-022-05034-x

Mesenchymal stem cells (MSCs) can be widely isolated from various tissues including bone marrow, umbilical cord, and adipose tissue, with the potential for self-renewal and multipotent differentiation. There is compelling evidence that the therapeutic effect of MSCs mainly depends on their paracrine action. Extracellular vesicles (EVs) are fundamental paracrine effectors of MSCs and play a crucial role in intercellular communication, existing in various body fluids and cell supernatants. Since MSC-derived EVs retain the function of protocells and have lower immunogenicity, they have a wide range of prospective therapeutic applications with advantages over cell therapy. We describe some characteristics of MSC-EVs, and discuss their role in immune regulation and regeneration, with emphasis on the molecular mechanism and application of MSC-EVs in the treatment of fibrosis and support tissue repair. We also highlight current challenges in the clinical application of MSC-EVs and potential ways to overcome the problem of quality heterogeneity.

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